Association between Helicobacter pylori infection,mismatch repair,HER2 and tumor-infiltrating lymphocytes in gastric cancer

BACKGROUND The influence of Helicobacter-pylori(H.pylori)infection and the characteristics of gastric cancer(GC)on tumor-infiltrating lymphocyte(TIL)levels has not been extensively studied.Analysis of infiltrating-immune-cell subtypes as well as survival is necessary to obtain comprehensive information.AIM To determine the rates of deficient mismatch-repair(dMMR),HER2-status and H.pylori infection and their association with TIL levels in GC.METHODS Samples from 503 resected GC tumors were included and TIL levels were evaluated following the international-TILs-working-group recommendations with assessment of the intratumoral(IT),stromal(ST)and invasive-border(IB)compartments.The density of CD3,CD8 and CD163 immune cells,and dMMR and HER2-status were determined by immunohistochemistry(IHC).H.pylori infection was evaluated by routine histology and quantitative PCR(qPCR)in a subset of samples.RESULTS dMMR was found in 34.4%,HER2+in 5%and H.pylori-positive in 55.7%of samples.High IT-TIL was associated with grade-3(P=0.038),while ST-TIL with grade-1(P<0.001),intestinal-histology(P<0.001)and no-recurrence(P=0.003).dMMR was associated with high TIL levels in the ST(P=0.019)and IB(P=0.01)compartments,and STCD3(P=0.049)and ST-CD8(P=0.05)densities.HER2-was associated with high IT-CD8(P=0.009).H.pylorinegative was associated with high IT-TIL levels(P=0.009)when assessed by routine-histology,and with high TIL levels in the 3 compartments(P=0.002-0.047)and CD8 density in the IT and ST compartments(P=0.001)when assessed by qPCR.A longer overall survival was associated with low IT-CD163(P=0.003)and CD8/CD3(P=0.001 in IT and P=0.002 in ST)and high IT-CD3(P=0.021),ST-CD3(P=0.003)and CD3/CD163(P=0.002).CONCLUSION TIL levels were related to dMMR and H.pylori-negativity.Low CD8/CD3 and high CD163/CD3 were associated with lower recurrence and longer survival.

Nrf2 and Her3 co-expression in cholangiocarcinoma:Possible biological pathways for potential therapeutic approach

To the Editor:Cholangiocarcinomas(CCAs)are heterogeneous group of malignancies,encompassing intrahepatic CCA(iCCA),and extrahepatic CCA(eCCA);they are also classified into common hepatic duct cholangiocarcinoma(CHDCCA),choledocus extrapancreatic cholangiocarcinoma(EPCCA)and choledocus intrapancreatic cholangiocarcinoma(IPCCA)and,finally,gallbladder carcinoma(GBCCA).CCAs are relatively uncommon but.

Operative link for gastritis assessment vs operative link on intestinal metaplasia assessment

AIM:To compare the reliability of gastritis staging sys-tems in ranking gastritis-associated cancer risk in a large series of consecutive patients.METHODS:Gastric mucosal atrophy is the precancer-ous condition in which intestinal-type gastric cancer(GC)most frequently develops.The operative link for gas-tritis assessment(OLGA)staging system ranks the GC risk according to both the topography and the severity of gastric atrophy(as assessed histologically on the ba-sis of the Sydney protocol for gastric mucosal biopsy).Both cross-sectional and long-term follow-up trials have consistently associated OLGA stages Ⅲ-Ⅳ with a higher risk of GC.A recently-proposed modification of the OLGA staging system(OLGIM)basically incorporates the OLGA frame,but replaces the atrophy score with an assessment of intestinal metaplasia(IM)alone.A series of 4552 consecutive biopsy sets(2007-2009)was re-trieved and reassessed according to both the OLGA and the OLGIM staging systems.A set of at least 5 biopsy samples was available for all the cases considered.RESULTS:In 4460 of 4552 cases(98.0%),both the high-risk stages(Ⅲ + Ⅳ)and the low-risk stages(0 +Ⅰ + Ⅱ)were assessed applying the OLGA and OL-GIM criteria.Among the 243 OLGA high-risk stages,14(5.8%)were down-staged to a low risk using OLGIM.The 67(1.5%)incidentally-found neoplastic lesions(intraepithelial or invasive)were consistently associated with high-risk stages,as assessed by both OLGA and OLGIM(P < 0.001 for both).Two of 34 intestinal-type GCs coexisting with a high-risk OLGA stage(stage Ⅲ)were associated with a low-risk OLGIM stage(stage Ⅱ).CONCLUSION:Gastritis staging systems(both OLGA and OLGIM)convey prognostically important informa-tion on the gastritis-associated cancer risk.Because of its clinical impact,the stage of gastritis should be included as a conclusive message in the gastritis histol-ogy report.Since it focuses on IM alone,OLGIM staging is less sensitive than OLGA staging in the identif ication of patients at high risk of gastric cancer.

Targeted therapies in metastatic gastric cancer: Current knowledge and future perspectives

Gastric cancer(GC)represents a leading cause of cancer related morbidity and mortality worldwide accounting for more than 1 million of newly diagnosed cases and thousands of deaths every year.In the last decade,the development of targeted therapies and the optimization of already available chemotherapeutic drugs has expanded the available treatment options for advanced GC and granted better survival expectations to the patients.At the same time,global efforts have been undertaken to investigate in detail the genomic and epigenomic heterogeneity of this disease,resulting in the identification of new specific and sensitive predictive and prognostic biomarkers and in innovative molecular classifications based on gene expression profiling.Nonetheless,several randomized studies aimed at exploring new innovative agents,such as immune checkpoint inhibitors,failed to demonstrate clinically meaningful survival advantages.Therefore,it is essential to further improve the molecular characterization of GC subgroups in order to provide researchers and medical oncologists with new tools for patients’selection and stratification in future clinical development programs and subsequent trials.The aim of the present manuscript is to provide a global overview of the recent molecular classifications from The Cancer Genome Atlas and the Asian Cancer Research Group and to present key promising developments in the field of immunotherapy and targeted therapies in metastatic GC.

Autoimmune gastritis:Pathologist's viewpoint

Western countries are seeing a constant decline in the incidence of Helicobacter pylori-associated gastritis, coupled with a rising epidemiological and clinical impact of autoimmune gastritis. This latter gastropathy is due to autoimmune aggression targeting parietal cells through a complex interaction of auto-antibodies against the parietal cell proton pump and intrinsic factor, and sensitized T cells. Given the specific target of this aggression, autoimmune gastritis is typically restricted to the gastric corpus-fundus mucosa. In advanced cases, the oxyntic epithelia are replaced by atrophic(and metaplastic) mucosa, creating the phenotypic background in which both gastric neuroendocrine tumors and(intestinal-type) adenocarcinomas may develop. Despite improvements in our understanding of the phenotypic changes or cascades occurring in this autoimmune setting, no reliable biomarkers are available for identifying patients at higher risk of developing a gastric neoplasm. The standardization of autoimmune gastritis histology reports and classifications in diagnostic practice is a prerequisite for implementing definitive secondary prevention strategies based on multidisciplinary diagnostic approaches integratingendoscopy, serology, histology and molecular profiling.

miRNAs in precancerous lesions of the gastrointestinal tract

In spite of the well-established understanding of the phenotypic lesions occurring in the shift from native epithelia to invasive （adeno） carcinoma, the molecular b/ping of the precancerous changes in the gastrointes- tinal tract remains unreliable. In recent years, no biomarkers have aroused as much interest as the miRNAs, a class of non-coding RNA molecules that function as endogenous silencers of numerous target genes. Aberrant miRNA expression is a hallmark of human disease, including cancer. Unlike most mRNAs, miRNAs are both long-living in vivo and very stable in vitro. Such charac- teristics allow their testing in paraffin-embedded tissue samples, which is essential in the biological profiling of small （phenotypically characterized） preneoplastic lesions of the gastrointestinal tract （as well as in other fields of human pathology）. The upcoming challenge lies in the reliable identification of disease-specific targets of dysregulated miRNAs, to enable miRNA testing in the clinical management of the secondary prevention of gastrointestinal cancer.

HER2 heterogeneity in gastric/gastroesophageal cancers: From benchside to practice

HER2 is overexpressed in approximately 10%-20% of gastric and gastroesophageal junction carcinomas. In these types of cancer, accurate assessment of HER2 status is mandatory, for selecting patients who may benefit from targeted therapies with anti-HER2 drugs such as Trastuzumab. This manuscript focuses on HER2 in gastric carcinogenesis, on optimal evaluation of HER2 and on the possible causes which may contribute to inaccurate HER2 evaluation. Similarly to breast cancer HER2 evaluation, standardization of HER2 testing in gastric cancer is necessary in diagnostic practice. The three principle aspects which require consideration are:(1) the choice of sample with regards to cancer morphology- intestinal vs diffuse areas;(2) the choice of scoring criteria- use of HER2 scoring criteria specific for gastric cancer; and(3) the choice of HER2 evaluation methods- use of an algorithm in which both immunohistochemistry and in situ hybridization play a role. Problematic issues include:(1) pre-analytic variables with particular emphasis on fixation;(2) recommended methodology for HER2 assessment(immunohistochemistry vs in situ hybridization);(3) HER2 heterogeneity both within the primary tumor and between primary tumor and metastases;(4) reliability of biopsies in HER 2 evaluation; and(5) quantity of sample(FFPE blocks from surgical specimens or endoscopic biopsies) necessary for an adequate assessment.

Noncoding RNAs as drivers of the phenotypic plasticity of oesophageal mucosa

The histological commitment of the lower oesophageal mucosa largely depends on a complex molecular landscape. After extended inflammatory insult due to gastroesophageal reflux disease,squamous oesophageal mucosa may differentiate into columnar metaplastic mucosa. In this setting,the presence of intestinal metaplasia is considered the starting point of Barrett's carcinogenetic cascade. Aside from secondary prevention strategies for Barrett's mucosa(BM) patients,there are multiple endoscopic ablative therapies available for BM eradication and for the replacement of metaplastic epithelia with a neosquamous mucosa. However,BM frequently recurs in a few years,which supports the notable phenotypic plasticity of the oesophageal mucosa. In recent years,several reports pinpointed a class of small noncoding RNAs,the micro RNAs(mi RNAs),as principal effectors and regulators of oesophageal mucosa metaplastic(and neoplastic) transformation. Because of mi RNAs notable stability in fixed archival diagnostic specimens,expression profiling of mi RNAs represent an innovative diagnostic,prognostic and predictive tool in the stratification of phenotypic alterations in the oesophageal mucosa.

Histopathological landscape of rare oesophageal neoplasms

The landscape of neoplastic pathology of the oesophagus is dominated by malignancies of epithelial origin,in particular by oesophageal adenocarcinoma and oesophageal squamous cell carcinoma.However,several other histopathological variants can be distinguished,some associated with peculiar histopathological profiles and prognostic behaviours and frequently underrecognized in clinical practice.The aim of this review is to provide a comprehensive characterization of the main morphological and clinical features of these rare variants of oesophageal neoplastic lesions.