GIPAD - Italian Group of Gastrointestinal Pathologists
Published: 2020-10-29
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Current prognostic and predictive biomarkers for gastrointestinal tumors in clinical practice

Review

Surgical Pathology Unit, Department of Medicine (DIMED), University of Padua, Italy
ARC-NET Research Centre, University of Verona, Italy; Department of Diagnostics and Public Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
Department of Pathology, University Hospital of Udine, Italy
Department of Public Health, Federico II University Medical School Naples, Italy
Center of Predictive Molecular Medicine, Center for Excellence on Aging and Translational Medicine, University of Chieti-Pescara, Italy
Vita e Salute University, Milan, Italy; Pathology Unit, Pancreas Translational and Clinical Research Center, IRCCS San Raffaele Scientific Institute, Milan, Italy
Department of Emergency and Organ Transplantation, Section of Pathological Anatomy, University of Bari Aldo Moro, Bari, Italy
Department of Pathology, Campus Bio-Medico University, Rome, Italy
Pathology Unit, Fondazione IRCCS Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy
https://orcid.org/0000-0003-0591-6723
Department of Diagnostics and Public Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
Anatomic Pathology, San Martino IRCCS Hospital, Genova, Italy; Anatomic Pathology, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genova, Italy
https://orcid.org/0000-0003-0193-5281
prognostic markers predictive markers targeted therapy molecular pathology immunohistochemistry

Abstract

The pathologist emerged in the personalized medicine era as a central actor in the definition of the most adequate diagnostic and therapeutic algorithms. In the last decade, gastrointestinal oncology has seen a significantly increased clinical request for the integration of novel prognostic and predictive biomarkers in histopathological reports. This request couples with the significant contraction of invasive sampling of the disease, thus conferring to the pathologist the role of governor for both proper pathologic characterization and customized processing of the biospecimens. This overview will focus on the most commonly adopted immunohistochemical and molecular biomarkers in the routine clinical characterization of gastrointestinal neoplasms referring to the most recent published recommendations, guidelines and expert opinions.

Introduction

Personalized medicine in oncology has pinpointed a central role of pathologists in the multidisciplinary team for the definition of the most adequate diagnostic and therapeutic algorithms 1. As a result, in the last decade, numerous novel prognostic and predictive biomarkers have been introduced and integrated in histopathological reports to obtain an inclusive morphological and molecular characterization of the biospecimens.

Several surgical pathology laboratories have implemented next generation sequencing (NGS) or multigene high-throughput technologies in their diagnostic portfolio; however, immunohistochemistry (IHC), in situ hybridization (ISH) and single gene analyses still retain a central role in the diagnostic scenario.

This overview will focus on the most commonly adopted immunohistochemical and molecular biomarkers in daily clinical characterization of gastrointestinal neoplasms referring to the most recent published recommendations, guidelines and expert opinions.

Gastroesophageal adenocarcinoma

HER2 OVEREXPRESSION/AMPLIFICATION

Definition and therapeutic implications

The HER2 (ERBB2) proto-oncogene is a member of the human epidermal growth factor receptor (HER/GFR/ERBB) family and encodes a transmembrane growth factor receptor with tyrosine kinase activity. HER2 gene amplification leads to HER2 protein overexpression, which is important for cancer initiation and progression.

The anti-HER2 monoclonal antibody trastuzumab in combination with standard chemotherapy has significantly improved response rate and survival outcome in patients harboring HER2-positive tumors (i.e. IHC 3+ or IHC 2+ and ISH+) 2,3. Moreover, other alternative HER2-targeted therapeutic approaches are in clinical trials with promising results 3. Thus, advanced gastroesophageal adenocarcinoma should be tested for HER2 status.

Clinical and pathological associated features

HER2 overexpression is observed in 15-20% gastroesophageal adenocarcinomas and has no significant prognostic impact.

The alteration is more common in intestinal-type adenocarcinomas than diffuse-type cancers, low-grade than high grade adenocarcinomas and gastroesophageal junction cancers than distal gastric adenocarcinomas 4.

Diagnosis

HER2 status may be clonally heterogeneous within the same tumor 5,6 and thus, HER2 testing should be performed on surgical samples or at least 6 biopsy samples 7,8. Moreover, in surgical samples, due to the presence of heterogeneous morphologic patterns is reasonable to select more than one tissue block for analysis. There is a high degree of concordance between primary and metastatic samples, hence, HER2 testing should be performed on the most representative material9. In biopsy samples, it should be kept in mind that low-grade and high-grade dysplastic lesions may present HER2 overexpression/gene amplification which can coexist with a HER2-negative invasive counterpart 10. Thus, an accurate combined morphological and IHC evaluation should be performed.

HER2 status should be assessed first by IHC, followed by ISH when IHC result is 2+ (equivocal). Positive (i.e. 3+) or negative (0 or 1+) staining do not require further ISH testing 11. The IHC evaluation should be performed according the Ruschoff/Hofmann scoring system (Fig. 1) 12. Note that, in comparison to breast cancer, the completeness of membrane staining is infrequent and expression is often seen in a basolateral pattern. For ISH, a ratio of HER2 signal to CEP17 signal of ≥ 2.0 is considered positive. The ISH analysis evaluation should preferably be performed in areas marked as strongest HER2 IHC intensity. Brightfield ISH techniques have been suggested to be superior than FISH in HER2 testing for gastroesophageal adenocarcinoma as they allow for easier identification of tumor nuclei in normal tissue 13.

EPSTEIN-BARR VIRUS INFECTION

Definition and therapeutic implications

The Epstein-Barr virus (EBV) is a DNA virus member of the herpes family, which has been associated with several types of cancer, including gastric carcinoma (GC). An EBV-positive gastric cancer category based on its genomic and molecular features was proposed by The Cancer Genome Atlas Research Network (TCGA) 14. This peculiar class of GC is usually characterized by overexpression of PD-L1 and shows high response rates to immunotherapy 15.

Clinical and pathological associated features

EBV infection is absent in gastric dysplasia or early GC, suggesting an EBV-specific carcinogenetic pathway 16. EBV is more often detected in moderate to poorly differentiated GCs, medullary histotype carcinomas and those involving the proximal stomach 17. EBV association is also noted in cancers of the gastric stump following surgery. Tumors often present abundant infiltrating lymphocytes, CDKN2A gene silencing, frequent PIK3CA mutations and a significant overexpression of PD-L1/PD-L2.

There is a male predominance and the prevalence is significantly higher among the Asian population in comparison to Caucasians. EBV-associated GCs have a low frequency of lymph node involvement and are characterized by an improved survival in comparison to EBV-negative cases 18.

Diagnosis

The gold standard assay for EBV is the targeting of EBV-encoded RNA (EBER) by ISH in paraffin-embedded samples 19. This method localizes the viral infection to the malignant cells with a moderate to strong nuclear staining. The presence of EBER-positive lymphocytes within tumor samples has been described and should not be considered in the definition of EBV-positivity 18.

Colorectal adenocarcinoma (CRC)

RAS GENES MUTATIONAL ANALYSIS

Definition and therapeutic implications

The RAS gene family is composed of four small cytoplasmic proteins with GTPase activity: H-Ras, K-Ras4a, K-Ras4b, and N-Ras. These proteins promote cell growth, differentiation, proliferation and survival.

Mutations in the RAS genes (KRAS and NRAS) are well-recognized biomarkers of resistance to anti-EGFR monoclonal antibodies 20-23.

Clinical and pathological associated features

KRAS mutations are an early event in colorectal carcinogenesis. In fact, there is a highly concordant rate (almost 95%) in paired primary cancers and metastatic samples 24,25. Cancers may present a mucinous histology and are usually located in the right colon.

Diagnosis

KRAS is mutated in approximately 40% of cases, mostly in exon 2 codons 12 (70-80%) and 13 (15-20%). The remaining mutations are mainly located in exon 3 codons 59-61 and in exon 4, which includes codons 117 and 146. Mutations in NRAS are present in approximately 3% to 5% of colorectal cancer samples particularly in exon 3 codon 61 (60%) and in exon 2 codons 12, 13 22.

NRAS mutations are typically mutually exclusive with KRAS and BRAF mutations.

Patients with CRC being considered for anti-EGFR therapy must be profiled for RAS mutational status 26. Different methods can be used, such as mutation-specific real-time polymerase chain reaction (RT-PCR), Sanger sequencing, pyrosequencing, BEAMing technique, and next-generation sequencing, among others. On the basis of the evidence that no improvement in the selection of patients for anti-EGFR therapy was obtained by adjusting the mutant allele fraction threshold in tissue samples from 5% (by pyrosequencing) to 1% (by NGS) 27, Colon Cancer Guidelines by Italian Association of Medical Oncology (AIOM) suggests that mutational analysis should carried out by a method with a sensitivity detection of 5% mutant allele fraction, at least in cases with high neoplastic cellularity (more than 50%) ()

BRAF GENE MUTATIONAL ANALYSIS

Definition and therapeutic implications

The BRAF gene encodes a serine/threonine protein kinase, which plays a role in regulating the MAPK/ERK signaling pathways, affecting cell growth and proliferation. Missense somatic mutations in the BRAF gene have been found in about 8-15% of metastatic CRCs 28.

The most common BRAF mutation (> 90%), resulting in a constitutive-active kinase, is a CTG → CAG transversion at residue 1799 (T1799A), leading to an amino acidic substitution from valine to glutamic acid at codon 600 (p.V600E) in exon 15.

BRAF mutations are observed in hyperplastic polyps and as an early event in the “serrated” carcinogenetic cascade 29. In the metastatic setting, BRAF-mutated CRCs have a poor prognosis and do not seem to benefit from EGFR inhibition 30. The phase III trial BEACON has recently proved a significant survival advantage associated with the combination of encorafenib plus cetuximab or the same doublet plus binimetinib compared to current standard treatments in BRAF-mutated tumors 31,32, paving the way for innovative BRAF-specific therapeutic options.

Clinical and pathological associated features

BRAF-mutated metastatic CRCs arise in older patient (> 60 years old) and with a higher prevalence in the female gender in comparison to BRAF-wild type cases, regardless of the MSI status 33-35. The proximal colon is the preferential location. Moreover, this class of tumors present a unique metastatic pattern, showing high rates of peritoneal metastases, distant lymph node metastases and low rates of lung metastases 28. However, no significant differences have been observed in liver or brain metastases rates 36.

From a histopathological point of view, BRAF-mutated CRCs frequently present mucinous features, poor differentiation and high stage at diagnosis 28; from the biological point of view, they mostly derived from serrated precursor lesions. Other less characteristic features include a higher frequency of tumor budding and signet ring cells histotype, infiltrative pattern of invasion with an increased risk of lympho-vascular albeit not perineural invasion, different grade of Tumor Infiltrating lymphocytes (TILs) and of peritumoral lymphoid reaction with follicular appearance (Crohn-like) 37.

CRCs bearing non-V600 BRAF mutations constitute a distinct clinico-pathological subset 38. BRAF mutations are grouped in activating RAS-independent signaling as monomers (class 1-V600E) or as dimers (class 2-codons 597/601), and RAS-dependent with impaired kinase activity (class 3-codons 594/596) 38,39. Class 3 CRCs usually are non-mucinous, microsatellite stable (MSS), arise on the left side of the colon of younger male patients, have no peritoneal spread, are lower grade at presentation and are related to a more favorable overall survival (OS) rate compared to both V600EBRAF mutants and wild-type CRCs, whereas class 2 lesions are clinically similar to V600EBRAF CRCs.

Diagnosis

BRAF mutational testing should be performed in metastatic CRCs for prognostic stratification, whereas there is insufficient evidence to support its testing as a predictive molecular biomarker for response to anti-EGFR inhibitors 26. The recent publication of the BEACON study pinpointed novel BRAF-targeting therapies in this oncological setting 31.

BRAF gene exon 15 mutational analyses can be performed as single gene analysis or in combination with the other RAS genes with high-throughput technologies. The VE1 clone has been demonstrated to be an alternative sensitive and specific immunohistochemical marker for the detection of BRAF p.V600E-mutated CRCs 40. However, considering the clinical and therapeutic implication of non-V600 mutations, the analysis of the most common exon 15 hotspots should be preferred.

Beyond the metastatic setting, V600EBRAF mutation is strongly associated with (~60%) the somatic inactivation of the DNA mismatch repair machinery (MMR) genes, which is virtually absent in Lynch syndrome 41. Hence, somatic BRAF mutation testing has been included into the Lynch syndrome screening algorithm (see below).

Pancancer biomarkers

DEFECTIVE DNA MISMATCH REPAIR COMPLEX (dMMR)/MICROSATELLITE INSTABILITY (MSI)

Definition and therapeutic implications

MMR is a highly conserved protein complex that recognizes and repairs erroneous short insertions, short deletions and single base mismatches that can arise during DNA replication and recombination. The most important MMR players include MLH1 (mutL homologue 1), MSH2 (mutS homologue 2), MSH6 (mutS homologue 6) and PMS2 (postmeiotic segregation increased 2) 42. These four proteins function in heterodimers, namely MLH1-PMS2 and MSH2-MSH6 43,44, where MLH1 and MSH2 are obligatory partners of these heterodimers. In fact, PMS2 and MSH6 can only form a heterodimer with MLH1 and MSH2, respectively. On the other hand, MLH1 and MHS2 can form heterodimers with other MMR proteins, namely MSH3, MLH3 and PMS1. An alteration in MLH1 and MSH2 results in subsequent proteolytic degradation of the mutated protein and its secondary partner, PMS2 and MSH6, respectively 44. Conversely, mutations in PMS2 or MSH6 may not result in proteolytic degradation of their primary partners.

The inactivation of these genes (i.e. dMMR) can occur due to germline and/or somatic mutations or epigenetic silencing, resulting in the accumulation of frame-shift mutations (either through insertions or deletions) with a subsequent increased mutational burden. Germline mutation(s) of the MMR genes is the hallmark of Lynch syndrome and constitutional mismatch repair deficiency (CMMRD) 45. Epigenetic silencing is usually represented by MLH1 gene promoter hypermethylation; secondary epigenetic silencing of MSH6 is observed after neoadjuvant radiochemotherapeutic treatments 46,47.

Microsatellites are repetitive DNA sequences that are distributed along the genome of both coding and noncoding regions and are particularly sensitive to DNA mismatching errors. The identification of microsatellite instability (MSI; i.e. clustering of mutations in microsatellites typically consisting of repeat length alterations) is, therefore, an indirect evidence of a dMMR 48. Of note, 6-7% of MSI tumors retain MMR IHC expression 49. Some of these cases presented an abnormal focal or dot-like nuclear MLH1 expression; some others were associated with an ultramutated status due to POLE mutations and subsequent alterations in the MMR machinery 49.

Importantly, for assessment tumor mutation burden, novel NGS approaches have been introduced to test MSI in the clinic, which have also been suggested in the analysis of non-Lynch associated cancers 49-51.

MMR screening/MSI testing has several important clinical implications: (i) dMMR/MSI universal screening in colorectal and endometrial cancers has been recommended to identify Lynch syndrome families 43,52; (ii) stage II/III colorectal cancers should be tested for dMMR/MSI because they do not benefit from 5-fluorouracil adjuvant therapy 53; (iii) dMMR/MSI tumors are eligible for immune checkpoint inhibitor therapies and are characterized by overexpression of PD-L1 15,54-56.

Clinical and pathological associated features

Patients with dMMR/MMR tumors are more often characterized by a prolonged overall survival in comparison to proficient MMR (pMMR)/MSS cases 14,57,58. However, there is a negative prognostic effect in patients treated with (neo)adjuvant chemotherapy 57,58.

dMMR/MSI has been well described in several types of human cancers, most frequently in colorectal (17% among all stages), endometrial (20%), and gastric (13%) adenocarcinomas 44,59, which are also the most frequently observed among Lynch syndrome patients.

Most dMMR/MSI tumors are characterized by a significant intra- and peri-neoplastic lymphocytic infiltration and phenotypic heterogeneity 60. In colorectal adenocarcinoma, dMMR/MSI status is associated with mucinous histology and rare histotypes such as medullary carcinoma and signet-ring cell adenocarcinoma 61,62. Thus, in experienced hands, histopathology can significantly improve the efficacy of dMMR/MSI detection. This consideration introduces the concept of the so-called “reflex test”, which can represent a molecular test directly performed by pathologist based on a peculiar morphological feature typically associated with a genetic profile (e.g.: medullary histology and MSI). This kind of approach can greatly reduce the overall diagnostic turnaround time in selected cases. On the other hand, remaining in the dMMR/MSI landscape, it has to be noticed that a small subset (~6%) of colorectal cancers with this genetic alteration have no detectable dMMR/MSI-specific histologic characteristics 62. In gastric adenocarcinoma, dMMR/MSI status is associated with intestinal-type histotype, an elderly age of onset and a distal location 63. In adenocarcinomas of the small intestine dMMR/MSI status has been observed in 8.3% of cases 44, is associated with a history of celiac disease 64 and with a mucinous histotype 65. Among gastrointestinal tumors with low prevalence of dMMR/MSI (< 5%), dMMR/MSI pancreatic ductal adenocarcinomas show medullary or mucinous/colloid histology and are associated with a KRAS/TP53 wild-type molecular background 66,67, dMMR/MSI cholangiocarcinomas show papillary and mucinous histotype 68.

Diagnosis

The use of immunohistochemistry to assess the presence or absence of MLH1, PMS2, MSH2 and MSH6 is recommended in all the patients with any sporadic cancer type belonging to the spectrum of cancers found in Lynch syndrome (i.e. colorectal, endometrial, small intestine, urothelial,central nervous system and sebaceous gland) 26. Due to the high concordance rate among IHC and PCR 69, IHC analysis is usually preferred over microsatellite instability testing. In fact, IHC has a lower turnaround time, allows to directly understand the altered gene(s) and requires a limited amount of tissue (i.e. 4 tissue slides). ESMO recommendations discourage the use of a two-antibody (i.e. PMS2 and MSH6) approach 44.

MMR protein expression is interpreted as (i) retained, when a moderate to strong expression (similar to what is observed in the stromal cells as internal control) is present in ≥ 10% tumor cells; (ii) loss, in case of complete loss of nuclear expression in cancer cells; (iii) indeterminate, if IHC staining intensity in tumor cells is lower than the internal control or the tumor is positive in < 10% (Fig. 2) 70. Indeterminate IHC results should undergo MSI testing.

False negative MMR immunostainings are mainly caused by pre-analytical issues, such as tissue fixation, but this can be easily recognized by the absence of signal in the internal positive controls (stromal cells or normal mucosa) 71. Another reason to retest the sample by MSI testing is the finding of aberrant staining patterns such as cytoplasmic, dot-like or perinuclear staining 71. False positive results (i.e. pMMR but MSI) may be determined by catalytically inactive mutated MMR proteins, which retain their antigenic integrity 71. MMR/microsatellite status heterogeneity has been described 15,72; in these cases, the analysis should be repeated on a representative sample of the metastatic disease.

In colorectal adenocarcinoma (and solely in this setting!), MLH1/PMS2 negative tumors should be tested for BRAF p.V600E since this mutation is frequently observed in sporadic cases 26. Another option to identify a MLH1/PMS2 negative tumor as sporadic is the evaluation of MLH1 promoter methylation 43. The latter diagnostic approach is also extended to other cancer types in addition to colorectal lesions; however, MLH1 constitutional methylation should be ruled out 73.

MSI testing is based on PCR amplification of microsatellite markers. Two possible panels are currently in use: (i) five microsatellites comprising two mononucleotide (BAT-25 and BAT-26) and three dinucleotide (D5S346, D2S123 and D17S250) repeats; (ii) five poly-A mononucleotide repeats (BAT-25, BAT-26, NR-21, NR-24, NR-27). Historically, loss of stability in 1 of the five microsatellite markers was defined as MSI-low and loss of stability in ≥ 2 as MSI-high. The term MSI-low should be abandoned and MSI-low tumours should be included within microsatellite stable tumours 74. The pentaplex panel of five poly-A mononucleotide repeats is the recommended panel given its higher sensitivity and specificity 75. Moreover, it may obviate the need for normal tissue for comparison, which is of central importance in the analysis of small biopsies obtained from cancer tissue.

Of note, a recent report demonstrated that almost 10% of patients had been enrolled for immunotherapy in metastatic colorectal cancer with a false positive dMMR or MSI-PCR result assessed by local laboratories 76. Thus, both MMR-IHC and MSI-PCR have to be performed in assessing the eligibility to treatment with immune checkpoint inhibitors.

NGS represents an appropriate alternative molecular test to assess MSI, especially in non-Lynch-associated tumors 77. However, NGS should be carried out only in selected centers experienced in these techniques.

PD-L1 EXPRESSION STATUS

Definition and therapeutic implications

Programmed death-ligand 1 (PD-L1; also known as CD247 or B7-H1) is one of the ligands of the programmed cell death 1 (PD-1) receptor, a dominant negative regulator of antitumor T cell effector function 56. PD-L1 is induced by inflammation and is expressed in the tumor microenvironment and on tumor cells. The blockade of the PD-1–PD-L1 interaction with therapeutic antibodies has emerged as an important therapeutic option in tumors overexpressing PD-L1 or tumors with an activation of T-cell immunoresponse such as in case of high tumor mutation burden or EBV associated gastric cancers. In fact, anti-PD-1/PD-L1 therapies result in T cell proliferation and infiltration into the tumor, inducing a cytotoxic T cell response that leads to an objective tumor response 15,78. Apart from colorectal cancer, in which dMMR/MSI status is the preferred predictive biomarker in the selection of patients for immunotherapy, PD-L1 expression emerged of importance for gastroesophageal cancers. FDA approved pembrolizumab (an anti PD-1 antibody) as a second-line standard of care therapy for patients with advanced or metastatic esophageal squamous cell carcinoma and PD-L1 combined positive score (CPS) ≥ 10 79,80 and as third-line option in metastatic gastroesophageal junction adenocarcinomas with a PD-L1 CPS ≥ 1 81.

Clinical and pathological associated features

In gastric cancer PD-L1 positivity is seen predominantly in the EBV-associated and dMMR/MSI tumors 15, although contrasting data are available on its prognostic impact. In colorectal adenocarcinomas, high level of PD-L1 expression has been associated to a poorer prognosis 82. In pancreatic ductal adenocarcinoma, the prognostic value of PD-L1 expression is still unclear; however, in the undifferentiated variant with osteoclast-like giant cells, its expression has been correlated with a poorer prognosis 83.

Diagnosis

Immunohistochemistry represents the gold standard for PD-L1 expression evaluation. Pathologists should be aware that this analysis is significantly affected by several factors: (i) different standardization protocols of PD-L1 assays, (ii) variability in PD-L1 antibody use among the different Institutions 84; (iii) different PD-L1 quantification scoring systems 85; and (iv) intratumor heterogeneity of PD-L1 expression 44. Moreover, PD-L1 is also expressed in pre-invasive lesions, which should be not considered in the evaluation 86,87.

PD-L1 positive controls are lung macrophages, placenta, spleen and tonsil, whereas negative staining are alveolar cells, hepatocytes and normal squamous epithelium.

In gastroesophageal carcinomas, PD-L1 evaluation is performed as CPS, which is the number of PD-L1 stained cells (i.e. tumor cells, lymphocytes, macrophages) dived by the total number of viable tumor cells, multiplied by 100 88. This is different from the Tumor Proportion Score (TPS), applied in non-small cell lung carcinoma, which is the percentage of viable tumor cells showing partial or complete membrane staining at any intensity.

At present, only pembrolizumab has indications restricted to tumors expressing PD-L1 (beyond dMMR/MSI status) and requires the use of a companion diagnostic, which is currently represented by the PD-L1 IHC 22C3 pharmDx (Dako). Other three antibodies have been approved by FDA for PD-L1 IHC assay: PD-L1 IHC 28-8 pharmDx assay for nivolumab treatment, VENTANA PD-L1 IHC (SP142) assay for atezolizumab treatment and VENTANA PD-L1 IHC (SP263) assay for durvalumab.

Other current and potential biomarkers with clinical impact

  1. Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract and should be profiled for KIT and PDGFRA due to their predictive value for tyrosine kinase inhibitors therapies 89-91. In fact, almost all KIT/PDGFRA alterations, but the PDGFRA p.D842V mutation, are activating the tyrosine kinases. KIT/PDGFRA mutations are present in around 85% of GISTs, the other 10-15% cases are usually characterized by mutations in SDH, NF1 or BRAF 92,93. KIT/PDGFRA alterations are usually tested by direct sequencing and NGS technologies.
  2. Recently, the therapeutic portfolio of biliary tract cancers has significantly improved with the introduction of targeted therapies associated with the molecular profile of the tumor 94. In particular, therapies targeting actionable genomic aberrations such as BRAF 95 or IDH1 96 mutations and FGFR2 gene fusions 97,98 have been successfully entered clinical development with significant responses and durable clinical benefit in selected patients. As a result, the demand for molecular profiling in this tumor setting will rapidly increase in our clinical practice. FGFR2 fusions can be detected by RNA-based NGS panels, but also RT-PCR-based kits have been recently introduced into the market.
  3. Amplification of the HER2 gene characterizes around 5% of KRAS/NRAS/BRAF wild type colorectal adenocarcinomas and HER2-targeting showed promising results in HER2-positive tumors refractory to standard of care therapies with EGFR inhibitors 99-101. HER2 assessment in colorectal cancer is performed according the HERACLES diagnostic criteria (i.e. 2+/3+ HER2-IHC in ≥ 50% tumor cells confirmed by FISH) 101.
  4. The analysis of neurotrophic tyrosine receptor kinase (NTRK) gene fusions has emerged as a predictive biomarker for the efficacy of inhibitors of the tropomyosin receptor kinase (TRK) proteins across a range of solid tumor types 102. In the gastrointestinal setting, NTRK gene fusions are extremely rare with a 0.23-0.31% prevalence in colorectal adenocarcinomas, 0.34% in pancreatic carcinomas, 0.25% in cholangiocarcinomas, 0.48% in appendiceal adenocarcinomas and 0.31% in neuroendocrine tumors 103,104. Of note, NTRK gene rearrangements are enriched in MLH1/PMS2 deficient and BRAF wild-type colorectal cancers, in which a 5.3% prevalence was described 105. Despite this relative rarity, the request for NTRK testing is increasing. NTRK alterations can be detected by immunohistochemistry, RT-PCR and RNA-based NGS.
  5. Germline and somatic mutations within the homologous recombination repair pathway (i.e. ATM, BRCA1, BRCA2 or PALB2) have been observed in pancreatic ductal adenocarcinoma and are associated with an increased sensitivity to platinum-based chemotherapy 106,107. Moreover, tumors with BRCA1/2 mutations display increased sensitivity to PARP inhibitors which, when used as maintenance therapy, result in a prolonged progression-free survival 108.
  6. SMAD4 is a genetic driver of pancreatic ductal adenocarcinoma; it is also known as DPC4 and is genetically inactivated in about half of pancreatic ductal adenocarcinomas (PDAC) 109. A reliable surrogate methodology to investigate its mutational status is represented by immunohistochemistry, with the loss of the nuclear expression of the protein indicating the genetic inactivation. SMAD4 mutations (SMAD4 immunohistochemical loss) have been correlated with widespread metastatic patterns in PDAC patients 110 and with higher rates of local and distant failure in those receiving adjuvant chemoradiation 111. Its determination may be useful for planning therapeutic decisions: although such situations are generally managed in ultra-specialized pancreatic centers, the presence of SMAD4 mutations may support radiofrequency ablation-based therapy 112.

Conclusions

We are facing molecularly-driven treatment choices for advanced gastrointestinal cancers and histopathologic diagnosis is becoming an integrated morphological and molecular characterization of the biospecimen. The pathologist should be aware of the novel therapies and how to improve the management of biospecimens in the personalized medicine era.

Figures and tables

Figure 1.HER2 testing in gastroesophageal adenocarcinomas. (A) Diagnostic algorithm modified from Bartley AN, et al.(11). Tumor cell cluster is defined as a cluster of five or more tumor cells. (B) Representative immunohistochemical examples of a negative (0) case showing no reactivity in any of the tumor cells, a negative (1+) case with faint/barely perceptible membranous staining, an equivocal 2+ immunoreaction and a strongly and diffuse 3+ positive case. CISH examples of a HER2 non-amplified and an amplified case are also shown.

Figure 2.Immunohistochemical interpretation of MMR proteins in colorectal adenocarcinoma. (A) Diagnostic algorithm for MMR staining interpretation modified from Remo, et al. (43). (B and C) Heterogeneous MMR protein expression. (B) The lesion was heterogeneous for MSH2/MSH6 status and proficient for MLH1/PMS2. The microdissected areas also showed a heterogeneous status of the MSI testing. (C) A heterogeneous MSH6 staining pattern observed in a MLH1 mutated Lynch syndrome patient. (D) A case of indeterminate positivity for MMR proteins, in which the staining intensity observed in cancer cells’ nuclei is significantly lower in comparison to surrounding stromal cells. This case was MSI at molecular testing.

References

  1. Fassan M. Molecular diagnostics in pathology: time for a next-generation pathologist?. Arch Pathol Lab Med. 2018; 142:313-20. DOI
  2. Bang YJ, Van Cutsem E, Feyereislova A. Trastuzumab in combination with chemotherapy versus chemotherapy alone for treatment of HER2-positive advanced gastric or gastro-oesophageal junction cancer (ToGA): a phase 3, open-label, randomised controlled trial. Lancet. 2010; 376(9742):687-97. DOI
  3. Pellino A, Riello E, Nappo F. Targeted therapies in metastatic gastric cancer: current knowledge and future perspectives. World J Gastroenterol. 2019; 25:5773-88. DOI
  4. Van Cutsem E, Bang YJ, Feng-Yi F. HER2 screening data from ToGA: targeting HER2 in gastric and gastroesophageal junction cancer. Gastric Cancer. 2015; 18:476-84. DOI
  5. Grillo F, Fassan M, Sarocchi F. HER2 heterogeneity in gastric/gastroesophageal cancers: From benchside to practice. World J Gastroenterol. 2016; 22:5879-87. DOI
  6. Grillo F, Fassan M, Fiocca R. Heterogeneous Her2/Neu expression in gastric and gastroesophageal cancer. Hum Pathol. 2016; 48:173-4. DOI
  7. Gullo I, Grillo F, Molinaro L. Minimum biopsy set for HER2 evaluation in gastric and gastro-esophageal junction cancer. Endosc Int Open. 2015; 3:E165-70. DOI
  8. Grillo F, Fassan M, Ceccaroli C. The reliability of endoscopic biopsies in assessing her2 status in gastric and gastroesophageal junction cancer: a study comparing biopsies with surgical samples. Transl Oncol. 2013; 6:10-6. DOI
  9. Amato M, Perrone G, Righi D. HER2 Status in Gastric Cancer: Comparison between Primary and Distant Metastatic Disease. Pathol Oncol Res. 2017; 23:55-61. DOI
  10. Fassan M, Mastracci L, Grillo F. Early HER2 dysregulation in gastric and oesophageal carcinogenesis. Histopathology. 2012; 61:769-76. DOI
  11. Bartley AN, Washington MK, Ventura CB. HER2 testing and clinical decision making in gastroesophageal adenocarcinoma: guideline From the College of American Pathologists, American Society for Clinical Pathology, and American Society of Clinical Oncology. Arch Pathol Lab Med. 2016; 140:1345-63. DOI
  12. Hofmann M, Stoss O, Shi D. Assessment of a HER2 scoring system for gastric cancer: results from a validation study. Histopathology. 2008; 52:797-805. DOI
  13. Fox SB, Kumarasinghe MP, Armes JE. Gastric HER2 Testing Study (GaTHER): an evaluation of gastric/gastroesophageal junction cancer testing accuracy in Australia. Am J Surg Pathol. 2012; 36:577-82. DOI
  14. Cancer Genome Atlas Research N. Comprehensive molecular characterization of gastric adenocarcinoma. Nature. 2014; 513(7517):202-9. DOI
  15. Kim ST, Cristescu R, Bass AJ. Comprehensive molecular characterization of clinical responses to PD-1 inhibition in metastatic gastric cancer. Nat Med. 2018; 24:1449-58. DOI
  16. Ribeiro J, Malta M, Galaghar A. Epstein-Barr virus is absent in gastric superficial neoplastic lesions. Virchows Arch. 2019; 475:757-62. DOI
  17. Ryan JL, Morgan DR, Dominguez RL. High levels of Epstein-Barr virus DNA in latently infected gastric adenocarcinoma. Lab Invest. 2009; 89:80-90. DOI
  18. Camargo MC, Kim WH, Chiaravalli AM. Improved survival of gastric cancer with tumour Epstein-Barr virus positivity: an international pooled analysis. Gut. 2014; 63:236-43. DOI
  19. Gulley ML, Tang W. Laboratory assays for Epstein-Barr virus-related disease. J Mol Diagn. 2008; 10:279-92. DOI
  20. Karapetis CS, Khambata-Ford S, Jonker DJ. K-ras mutations and benefit from cetuximab in advanced colorectal cancer. N Engl J Med. 2008; 359:1757-65. DOI
  21. Van Cutsem E, Kohne CH, Hitre E. Cetuximab and chemotherapy as initial treatment for metastatic colorectal cancer. N Engl J Med. 2009; 360:1408-17. DOI
  22. De Roock W, Claes B, Bernasconi D. Effects of KRAS, BRAF, NRAS, and PIK3CA mutations on the efficacy of cetuximab plus chemotherapy in chemotherapy-refractory metastatic colorectal cancer: a retrospective consortium analysis. Lancet Oncol. 2010; 11:753-62. DOI
  23. Douillard JY, Oliner KS, Siena S. Panitumumab-FOLFOX4 treatment and RAS mutations in colorectal cancer. N Engl J Med. 2013; 369:1023-34. DOI
  24. Han CB, Li F, Ma JT, Zou HW. Concordant KRAS mutations in primary and metastatic colorectal cancer tissue specimens: a meta-analysis and systematic review. Cancer Invest. 2012; 30:741-7. DOI
  25. Santini D, Loupakis F, Vincenzi B. High concordance of KRAS status between primary colorectal tumors and related metastatic sites: implications for clinical practice. Oncologist. 2008; 13:1270-5. DOI
  26. Sepulveda AR, Hamilton SR, Allegra CJ. Molecular biomarkers for the evaluation of colorectal cancer: guideline From the American Society for Clinical Pathology, College of American Pathologists, Association for Molecular Pathology, and American Society of Clinical Oncology. Arch Pathol Lab Med. 2017; 141:625-57. DOI
  27. Vidal J, Bellosillo B, Santos Vivas C. Ultra-selection of metastatic colorectal cancer patients using next-generation sequencing to improve clinical efficacy of anti-EGFR therapy. Ann Oncol. 2019; 30:439-46. DOI
  28. Fanelli GN, Dal Pozzo CA, Depetris I. The heterogeneous clinical and pathological landscapes of metastatic Braf-mutated colorectal cancer. Cancer Cell Int. 2020; 20:30. DOI
  29. Barras D. BRAF mutation in colorectal cancer: an update. Biomark Cancer. 2015; 7:9-12. DOI
  30. Rowland A, Dias MM, Wiese MD. Meta-analysis of BRAF mutation as a predictive biomarker of benefit from anti-EGFR monoclonal antibody therapy for RAS wild-type metastatic colorectal cancer. Br J Cancer. 2015; 112:1888-94. DOI
  31. Kopetz S, Grothey A, Yaeger R. Encorafenib, binimetinib, and cetuximab in braf v600e-mutated colorectal cancer. N Engl J Med. 2019; 381:1632-43. DOI
  32. Van Cutsem E, Huijberts S, Grothey A. Binimetinib, encorafenib, and cetuximab triplet therapy for patients With Braf v600e-mutant metastatic colorectal cancer: safety lead-in results from the Phase III beacon colorectal cancer study. J Clin Oncol. 2019; 37:1460-9. DOI
  33. Clancy C, Burke JP, Kalady MF. BRAF mutation is associated with distinct clinicopathological characteristics in colorectal cancer: a systematic review and meta-analysis. Colorectal Dis. 2013; 15:e711-8. DOI
  34. Loupakis F, Intini R, Cremolini C. A validated prognostic classifier for (V600E)BRAF-mutated metastatic colorectal cancer: the ‘BRAF BeCool’ study. Eur J Cancer. 2019; 118:121-30. DOI
  35. Loupakis F, Biason P, Prete AA. CK7 and consensus molecular subtypes as major prognosticators in (V600E)BRAF mutated metastatic colorectal cancer. Br J Cancer. 2019; 121:593-9. DOI
  36. Tran B, Kopetz S, Tie J. Impact of BRAF mutation and microsatellite instability on the pattern of metastatic spread and prognosis in metastatic colorectal cancer. Cancer. 2011; 117:4623-32. DOI
  37. Jang MH, Kim S, Hwang DY. BRAF-Mutated Colorectal Cancer Exhibits Distinct Clinicopathological Features from Wild-Type BRAF-Expressing Cancer Independent of the Microsatellite Instability Status. J Korean Med Sci. 2017; 32:38-46. DOI
  38. Schirripa M, Biason P, Lonardi S. Class 1, 2, and 3 BRAF-Mutated Metastatic Colorectal Cancer: A Detailed Clinical, Pathologic, and Molecular Characterization. Clin Cancer Res. 2019; 25:3954-61. DOI
  39. Cremolini C, Di Bartolomeo M, Amatu A. BRAF codons 594 and 596 mutations identify a new molecular subtype of metastatic colorectal cancer at favorable prognosis. Ann Oncol. 2015; 26:2092-7. DOI
  40. Galuppini F, Pennelli G, Loupakis F. BRAF p.V600E-specific immunohistochemical assessment in colorectal cancer endoscopy biopsies is consistent with the mutational profiling. Histopathology. 2017; 71:1008-11. DOI
  41. Parsons MT, Buchanan DD, Thompson B. Correlation of tumour BRAF mutations and MLH1 methylation with germline mismatch repair (MMR) gene mutation status: a literature review assessing utility of tumour features for MMR variant classification. J Med Genet. 2012; 49:151-7. DOI
  42. Boland CR, Goel A. Microsatellite instability in colorectal cancer. Gastroenterology. 2010; 138(6):2073-87 e3. DOI
  43. Remo A, Fassan M, Lanza G. Immunohistochemical evaluation of mismatch repair proteins in colorectal carcinoma: the AIFEG/GIPAD proposal. Pathologica. 2016; 108:104-9.
  44. Luchini C, Bibeau F, Ligtenberg MJL. ESMO recommendations on microsatellite instability testing for immunotherapy in cancer, and its relationship with PD-1/PD-L1 expression and tumour mutational burden: a systematic review-based approach. Ann Oncol. 2019; 30:1232-43. DOI
  45. Galuppini F, Opocher E, Tabori U. Concomitant IDH wild-type glioblastoma and IDH1-mutant anaplastic astrocytoma in a patient with constitutional mismatch repair deficiency syndrome. Neuropathol Appl Neurobiol. 2018; 44:233-9. DOI
  46. Indraccolo S, Lombardi G, Fassan M. Genetic, epigenetic, and immunologic profiling of MMR-Deficient Relapsed Glioblastoma. Clin Cancer Res. 2019; 25:1828-37. DOI
  47. Bao F, Panarelli NC, Rennert H. Neoadjuvant therapy induces loss of MSH6 expression in colorectal carcinoma. Am J Surg Pathol. 2010; 34:1798-804. DOI
  48. Ma J, Setton J, Lee NY. The therapeutic significance of mutational signatures from DNA repair deficiency in cancer. Nat Commun. 2018; 9:3292. DOI
  49. Hechtman JF, Rana S, Middha S. Retained mismatch repair protein expression occurs in approximately 6% of microsatellite instability-high cancers and is associated with missense mutations in mismatch repair genes. Mod Pathol. 2020; 33:871-9. DOI
  50. Niu B, Ye K, Zhang Q. MSIsensor: microsatellite instability detection using paired tumor-normal sequence data. Bioinformatics. 2014; 30:1015-6. DOI
  51. Galuppini F, Dal Pozzo CA, Deckert J. Tumor mutation burden: from comprehensive mutational screening to the clinic. Cancer Cell Int. 2019; 19:209. DOI
  52. Hechtman JF, Middha S, Stadler ZK. Universal screening for microsatellite instability in colorectal cancer in the clinical genomics era: new recommendations, methods, and considerations. Fam Cancer. 2017; 16:525-9. DOI
  53. Popat S, Hubner R, Houlston RS. Systematic review of microsatellite instability and colorectal cancer prognosis. J Clin Oncol. 2005; 23:609-18. DOI
  54. Overman MJ, Lonardi S, Wong KYM. Durable clinical benefit with nivolumab plus ipilimumab in dna mismatch repair-deficient/microsatellite instability-high metastatic colorectal cancer. J Clin Oncol. 2018; 36:773-9. DOI
  55. Overman MJ, McDermott R, Leach JL. Nivolumab in patients with metastatic DNA mismatch repair-deficient or microsatellite instability-high colorectal cancer (CheckMate 142): an open-label, multicentre, phase 2 study. Lancet Oncol. 2017; 18:1182-91. DOI
  56. Ribas A, Wolchok JD. Cancer immunotherapy using checkpoint blockade. Science. 2018; 359(6382):1350-5. DOI
  57. Guinney J, Dienstmann R, Wang X. The consensus molecular subtypes of colorectal cancer. Nat Med. 2015; 21:1350-6. DOI
  58. Smyth EC, Wotherspoon A, Peckitt C. Mismatch repair deficiency, microsatellite instability, and survival: an exploratory analysis of the Medical Research Council Adjuvant Gastric Infusional Chemotherapy (MAGIC) Trial. JAMA Oncol. 2017; 3:1197-203. DOI
  59. Bonneville R, Krook MA, Kautto EA. Landscape of Microsatellite Instability Across 39 Cancer Types. JCO Precis Oncol. 2017; 2017DOI
  60. Loupakis F, Depetris I, Biason P. Prediction of benefit from checkpoint inhibitors in mismatch repair deficient metastatic colorectal cancer: role of tumor infiltrating lymphocytes. Oncologist. 2020; 25:481-7. DOI
  61. Shia J, Schultz N, Kuk D. Morphological characterization of colorectal cancers in The Cancer Genome Atlas reveals distinct morphology-molecular associations: clinical and biological implications. Mod Pathol. 2017; 30:599-609. DOI
  62. Shia J, Holck S, Depetris G. Lynch syndrome-associated neoplasms: a discussion on histopathology and immunohistochemistry. Fam Cancer. 2013; 12:241-60. DOI
  63. Mathiak M, Warneke VS, Behrens HM. Clinicopathologic characteristics of microsatellite instable gastric carcinomas revisited: urgent need for standardization. Appl Immunohistochem Mol Morphol. 2017; 25:12-24. DOI
  64. Giuffrida P, Arpa G, Grillo F. PD-L1 in small bowel adenocarcinoma is associated with etiology and tumor-infiltrating lymphocytes, in addition to microsatellite instability. Mod Pathol. 2020; 33:1398-1409. DOI
  65. Jun SY, Lee EJ, Kim MJ. Lynch syndrome-related small intestinal adenocarcinomas. Oncotarget. 2017; 8:21483-500. DOI
  66. Luchini C, Brosens LAA, Wood LD. Comprehensive characterisation of pancreatic ductal adenocarcinoma with microsatellite instability: histology, molecular pathology and clinical implications. Gut. 2020. DOI
  67. Luchini C, Capelli P, Scarpa A. Pancreatic ductal adenocarcinoma and its variants. Surg Pathol Clin. 2016; 9:547-60. DOI
  68. Goeppert B, Roessler S, Renner M. Mismatch repair deficiency is a rare but putative therapeutically relevant finding in non-liver fluke associated cholangiocarcinoma. Br J Cancer. 2019; 120:109-14. DOI
  69. Latham A, Srinivasan P, Kemel Y. Microsatellite Instability Is Associated With the Presence of Lynch Syndrome Pan-Cancer. J Clin Oncol. 2019; 37:286-95. DOI
  70. Sarode VR, Robinson L. Screening for lynch syndrome by immunohistochemistry of mismatch repair proteins: significance of indeterminate result and correlation with mutational studies. Arch Pathol Lab Med. 2019; 143:1225-33. DOI
  71. Shia J. Immunohistochemistry versus microsatellite instability testing for screening colorectal cancer patients at risk for hereditary nonpolyposis colorectal cancer syndrome. Part I. The utility of immunohistochemistry. J Mol Diagn. 2008; 10:293-300. DOI
  72. Loupakis F, Maddalena G, Depetris I. Treatment with checkpoint inhibitors in a metastatic colorectal cancer patient with molecular and immunohistochemical heterogeneity in MSI/dMMR status. J Immunother Cancer. 2019; 7:297. DOI
  73. Pinto D, Pinto C, Guerra J. Contribution of MLH1 constitutional methylation for Lynch syndrome diagnosis in patients with tumor MLH1 downregulation. Cancer Med. 2018; 7:433-44. DOI
  74. Umar A, Boland CR, Terdiman JP. Revised bethesda guidelines for hereditary nonpolyposis colorectal cancer (lynch syndrome) and microsatellite instability. J Natl Cancer Inst. 2004; 96:261-8. DOI
  75. Goel A, Nagasaka T, Hamelin R. An optimized pentaplex PCR for detecting DNA mismatch repair-deficient colorectal cancers. PLoS One. 2010; 5:e9393. DOI
  76. Cohen R, Hain E, Buhard O. Association of primary resistance to immune checkpoint inhibitors in metastatic colorectal cancer with misdiagnosis of microsatellite instability or mismatch repair deficiency status. JAMA Oncol. 2019; 5:551-5. DOI
  77. Nowak JA, Yurgelun MB, Bruce JL. Detection of mismatch repair deficiency and microsatellite instability in colorectal adenocarcinoma by targeted next-generation sequencing. J Mol Diagn. 2017; 19:84-91. DOI
  78. Baumeister SH, Freeman GJ, Dranoff G. coinhibitory pathways in immunotherapy for cancer. Annu Rev Immunol. 2016; 34:539-73. DOI
  79. Shah MA, Kojima T, Hochhauser D. Efficacy and safety of pembrolizumab for heavily pretreated patients with advanced, metastatic adenocarcinoma or squamous cell carcinoma of the esophagus: the phase 2 KEYNOTE-180 study. JAMA Oncol. 2019; 5:546-50. DOI
  80. Kojima T, Muro K, Francois E. Pembrolizumab versus chemotherapy as second-line therapy for advanced esophageal cancer: Phase III KEYNOTE-181 study. J Clin Oncol. 2019; 37:2.
  81. Fashoyin-Aje L, Donoghue M, Chen H. FDA approval summary: pembrolizumab for recurrent locally advanced or metastatic gastric or gastroesophageal junction adenocarcinoma expressing PD-L1. Oncologist. 2019; 24:103-9. DOI
  82. Li Y, He M, Zhou Y. The prognostic and clinicopathological roles of PD-L1 expression in colorectal cancer: a systematic review and meta-analysis. Front Pharmacol. 2019; 10:139. DOI
  83. Luchini C, Cros J, Pea A. PD-1, PD-L1, and CD163 in pancreatic undifferentiated carcinoma with osteoclast-like giant cells: expression patterns and clinical implications. Hum Pathol. 2018; 81:157-65. DOI
  84. Ahn S, Lee Y, Kim JW. Programmed cell death ligand-1 (PD-L1) expression in extrahepatic biliary tract cancers: a comparative study using 22C3, SP263 and E1L3N anti-PD-L1 antibodies. Histopathology. 2019; 75:526-36. DOI
  85. Shitara K, Ozguroglu M, Bang YJ. Pembrolizumab versus paclitaxel for previously treated, advanced gastric or gastro-oesophageal junction cancer (KEYNOTE-061): a randomised, open-label, controlled, phase 3 trial. Lancet. 2018; 392(10142):123-33. DOI
  86. Fassan M, Brignola S, Pennelli G. PD-L1 expression in gastroesophageal dysplastic lesions. Virchows Arch. 2019. DOI
  87. Saraggi D, Galuppini F, Remo A. PD-L1 overexpression in ampulla of Vater carcinoma and its pre-invasive lesions. Histopathology. 2017; 71:470-4. DOI
  88. Kulangara K, Zhang N, Corigliano E. Clinical utility of the combined positive score for programmed death ligand-1 expression and the approval of pembrolizumab for treatment of gastric cancer. Arch Pathol Lab Med. 2019; 143:330-7. DOI
  89. Rossi S, Gasparotto D, Miceli R. KIT, PDGFRA, and BRAF mutational spectrum impacts on the natural history of imatinib-naive localized GIST: a population-based study. Am J Surg Pathol. 2015; 39:922-30. DOI
  90. Ricci R, Saragoni L. Everything you always wanted to know about GIST (but were afraid to ask) An update on GIST pathology. Pathologica. 2016; 108:90-103.
  91. Corless CL. Gastrointestinal stromal tumors: what do we know now?. Mod Pathol. 2014; 27:S1-16. DOI
  92. Pantaleo MA, Biasco G. Gastrointestinal cancer: management of GIST--go beyond imatinib: treat resistant subtypes. Nat Rev Clin Oncol. 2015; 12:440-2. DOI
  93. Origone P, Gargiulo S, Mastracci L. Molecular characterization of an Italian series of sporadic GISTs. Gastric Cancer. 2013; 16:596-601. DOI
  94. Athauda A, Fong C, Lau DK. Broadening the therapeutic horizon of advanced biliary tract cancer through molecular characterisation. Cancer Treat Rev. 2020; 86:101998. DOI
  95. Wainberg ZA, Lassen UN, Elez E. Efficacy and safety of dabrafenib (D) and trametinib (T) in patients (pts) with BRAF V600E–mutated biliary tract cancer (BTC): a cohort of the ROAR basket trial. J Clin Oncol. 2019; 37:187.
  96. Lowery MA, Burris HA, Janku F. Safety and activity of ivosidenib in patients with IDH1-mutant advanced cholangiocarcinoma: a phase 1 study. Lancet Gastroenterol Hepatol. 2019; 4:711-20. DOI
  97. Mazzaferro V, El-Rayes BF, Droz Dit Busset M. Derazantinib (ARQ 087) in advanced or inoperable FGFR2 gene fusion-positive intrahepatic cholangiocarcinoma. Br J Cancer. 2019; 120:165-71. DOI
  98. Javle M, Lowery M, Shroff RT. Phase II Study of BGJ398 in patients with FGFR-altered advanced cholangiocarcinoma. J Clin Oncol. 2018; 36:276-82. DOI
  99. Sartore-Bianchi A, Amatu A, Porcu L. HER2 Positivity Predicts Unresponsiveness to EGFR-Targeted Treatment in Metastatic Colorectal Cancer. Oncologist. 2019; 24:1395-402. DOI
  100. Sartore-Bianchi A, Trusolino L, Martino C. Dual-targeted therapy with trastuzumab and lapatinib in treatment-refractory, KRAS codon 12/13 wild-type, HER2-positive metastatic colorectal cancer (HERACLES): a proof-of-concept, multicentre, open-label, phase 2 trial. Lancet Oncol. 2016; 17:738-46. DOI
  101. Valtorta E, Martino C, Sartore-Bianchi A. Assessment of a HER2 scoring system for colorectal cancer: results from a validation study. Mod Pathol. 2015; 28:1481-91. DOI
  102. Yoshino T, Pentheroudakis G, Mishima S. JSCO-ESMO-ASCO-JSMO-TOS: international expert consensus recommendations for tumour-agnostic treatments in patients with solid tumours with microsatellite instability or NTRK fusions. Ann Oncol. 2020; 31:861-72. DOI
  103. Lasota J, Chlopek M, Lamoureux J. colonic adenocarcinomas harboring NTRK fusion genes: a clinicopathologic and molecular genetic study of 16 cases and review of the literature. Am J Surg Pathol. 2020; 44:162-73. DOI
  104. Solomon JP, Linkov I, Rosado A. NTRK fusion detection across multiple assays and 33,997 cases: diagnostic implications and pitfalls. Mod Pathol. 2020; 33:38-46. DOI
  105. Chou A, Fraser T, Ahadi M. NTRK gene rearrangements are highly enriched in MLH1/PMS2 deficient, BRAF wild-type colorectal carcinomas-a study of 4569 cases. Mod Pathol. 2020; 33:924-32. DOI
  106. Waddell N, Pajic M, Patch AM. Whole genomes redefine the mutational landscape of pancreatic cancer. Nature. 2015; 518(7540):495-501. DOI
  107. Hutchings D, Jiang Z, Skaro M. Histomorphology of pancreatic cancer in patients with inherited ATM serine/threonine kinase pathogenic variants. Mod Pathol. 2019; 32:1806-13. DOI
  108. Golan T, Hammel P, Reni M. Maintenance olaparib for germline BRCA-mutated metastatic pancreatic cancer. N Engl J Med. 2019; 381:317-27. DOI
  109. Huang W, Navarro-Serer B, Jeong YJ. Pattern of invasion in human pancreatic cancer organoids is associated with loss of SMAD4 and clinical outcome. Cancer Res. 2020. DOI
  110. Iacobuzio-Donahue CA, Fu B, Yachida S. DPC4 gene status of the primary carcinoma correlates with patterns of failure in patients with pancreatic cancer. J Clin Oncol. 2009; 27:1806-13. DOI
  111. Herman JM, Jabbour SK, Lin SH. Smad4 Loss correlates with higher rates of local and distant failure in pancreatic adenocarcinoma patients receiving adjuvant chemoradiation. Pancreas. 2018; 47:208-12. DOI
  112. Paiella S, Malleo G, Cataldo I. Radiofrequency ablation for locally advanced pancreatic cancer: SMAD4 analysis segregates a responsive subgroup of patients. Langenbecks Arch Surg. 2018; 403:213-20. DOI

Affiliations

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$authorString->getFullName() => Matteo Fassan

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Matteo Fassan

Surgical Pathology Unit, Department of Medicine (DIMED), University of Padua, Italy
non esiste orcidID ""

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$authorString->getFullName() => Aldo Scarpa

$authorString->getUrl() =>

Aldo Scarpa

ARC-NET Research Centre, University of Verona, Italy; Department of Diagnostics and Public Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
non esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Andrea Remo

$authorString->getUrl() =>

Andrea Remonon esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Giovanna De Maglio

$authorString->getUrl() =>

Giovanna De Maglio

Department of Pathology, University Hospital of Udine, Italy
non esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Giancarlo Troncone

$authorString->getUrl() =>

Giancarlo Troncone

Department of Public Health, Federico II University Medical School Naples, Italy
non esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Antonio Marchetti

$authorString->getUrl() =>

Antonio Marchetti

Center of Predictive Molecular Medicine, Center for Excellence on Aging and Translational Medicine, University of Chieti-Pescara, Italy
non esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Claudio Doglioni

$authorString->getUrl() =>

Claudio Doglioni

Vita e Salute University, Milan, Italy; Pathology Unit, Pancreas Translational and Clinical Research Center, IRCCS San Raffaele Scientific Institute, Milan, Italy
non esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Giuseppe Ingravallo

$authorString->getUrl() =>

Giuseppe Ingravallo

Department of Emergency and Organ Transplantation, Section of Pathological Anatomy, University of Bari Aldo Moro, Bari, Italy
non esiste orcidID ""

$authorString->getOrcid() =>

$authorString->getFullName() => Giuseppe Perrone

$authorString->getUrl() =>

Giuseppe Perrone

Department of Pathology, Campus Bio-Medico University, Rome, Italy
non esiste orcidID ""

$authorString->getOrcid() => https://orcid.org/0000-0003-0591-6723

$authorString->getFullName() => Paola Parente

$authorString->getUrl() =>

Paola Parente

Pathology Unit, Fondazione IRCCS Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy
esiste orcidID "https://orcid.org/0000-0003-0591-6723" https://orcid.org/0000-0003-0591-6723

$authorString->getOrcid() =>

$authorString->getFullName() => Claudio Luchini

$authorString->getUrl() =>

Claudio Luchini

Department of Diagnostics and Public Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
non esiste orcidID ""

$authorString->getOrcid() => https://orcid.org/0000-0003-0193-5281

$authorString->getFullName() => Luca Mastracci

$authorString->getUrl() =>

Luca Mastracci

Anatomic Pathology, San Martino IRCCS Hospital, Genova, Italy; Anatomic Pathology, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genova, Italy
esiste orcidID "https://orcid.org/0000-0003-0193-5281" https://orcid.org/0000-0003-0193-5281

Copyright

© Società Italiana di Anatomia Patologica e Citopatologia Diagnostica, Divisione Italiana della International Academy of Pathology , 2020

How to Cite

[1]
Fassan, M., Scarpa, A., Remo, A., De Maglio, G., Troncone, G., Marchetti, A., Doglioni, C., Ingravallo, G., Perrone, G., Parente, P., Luchini, C. and Mastracci, L. 2020. Current prognostic and predictive biomarkers for gastrointestinal tumors in clinical practice: Review. Pathologica - Journal of the Italian Society of Anatomic Pathology and Diagnostic Cytopathology. 112, 3 (Oct. 2020), 248-259. DOI:https://doi.org/10.32074/1591-951X-158.
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