Патоморфологические и молекулярно-генетические особенности диффузного типа рака желудка

 Gastric cancer (GC) is the 5th most common type of cancer in the world and the third leading cause of death from cancer. GC is a multi-factorial and morphologically heterogeneous disease. Currently, several morphological classifications of GC are used, however, for diagnosis, it is necessary to take into  account not only the morphological type of the tumor, but also its molecular subtype. According to the literature, the intestinal type of GC is most often associated with effects of environmental factors and is usually found in older  age groups in men, while diffuse gastric cancer (DGC) is a genetically determined disease which is more common in younger patients, with the same frequency among men and women.This review covers in detail GC, its classification by P.A. Lauren (1965), and its molecular subtypes characterized during the Cancer Genome Atlas project and examines the impact of certain risk factors on the pathogenesis of the disease, such as: H. pylori infection or Epstein – Barr virus. A separate section in this analytical work is dedicated to expression of the PD-L1 marker by tumor cells and the use of this parameter for prognosis and therapy of this disease. An essential part of the work is discussion of the features of intestinal and diffuse types of gastric cancer, which reflect not only the differences in classifications used in modern diagnosis, but also the relationship between the pathological pattern and the molecular subtype of gastric cancer.  Рак желудка (РЖ) занимает пятое место в мире по распространенности среди всех злокачественных новообразований и является третьей по значимости причиной смертности от онкологических заболеваний. РЖ является мультифакториальным, морфологически  неоднородным заболеванием. В настоящее время используется несколько морфологических классификаций  РЖ, однако для постановки диагноза требуется учитывать не только морфологический тип опухоли, но и ее  молекулярный подтип. По данным литературы, РЖ  интестинального типа чаще всего ассоциирован с  действием факторов окружающей среды и, как правило, встречается в старших возрастных группах у мужчин.  Диффузный тип рака желудка (ДТРЖ) является в большей степени генетически детерминированным заболеванием и чаще встречается у более молодых пациентов, при этом с одинаковой частотой среди мужчин и женщин.В данном обзоре подробно освещается тема РЖ, его  классификация по P.A. Lauren (1965), его молекулярным  подтипы, охарактеризованные в Атласе ракового генома  (The Cancer Genome Atlas), а также рассматривается влияние  определенных факторов риска на патогенез  заболевания, таких как инфицирование H. pylori или вирусом Эпштейна – Барр. Отдельную роль в данной  аналитической работе занимает вопрос экспрессии опухолевыми клетками маркера PD-L1 и использование  данного параметра для прогнозирования и терапии этого  заболевания. Немаловажной частью работы является  обсуждение особенностей интестинального и диффузного  типов рака желудка, которые отражают не только различия  используемых в современной диагностике классификаций,  но и взаимосвязь патоморфологической картины с  молекулярным подтипом рака желудка.

Genetic and histological subtypes of gastric cancer reviewed, particularly emphasising on microsatellite instability and E-cadherin gene mutation

Almost one million new cases of gastric cancer (GC) were estimated globally in 2012, (i.e. 952,000, representing 6.8% of the total cancer burden), making it the fifth most common malignancy in the world. GC represents a biologically and genetically diverse group of tumours with multifactorial aetiologies; both environmental and genetic. The vast majority of GCs are adenocarcinomas, which can be further subdivided into intestinal and diffuse histological subtypes according to the Lauren classification published in 1965. The molecular classification of GC according to the Cancer Genome Atlas (TCGA) divides GC into four subtypes: tumours positive for the EBV virus (9%), microsatellite unstable tumours (22%), genomically stable tumours (20%) and tumours with chromosomal instability (CIN) at 50%. Most GCs are sporadic by nature, where approximately 10% appear to possess a familial predisposition of which around half can be attributed to hereditary germline mutations i.e. those of the E-cadherin (CDH1) or mismatch repair (MMR) genes. Histopathological characteristics of the tumour type and analysis of potential genetic changes have substantial cli­nical significance, as they determine the choice of treatment. In this review, we consider the molecular pathogenesis, phenotype and testing of GC placing particular emphasis on microsatellite instability (MSI) and the CDH1 mutation

Genetic and histological subtypes of gastric cancer reviewed, particularly emphasising on microsatellite instability and E-cadherin gene mutation

Almost one million new cases of gastric cancer (GC) were estimated globally in 2012, (i.e. 952,000, representing 6.8% of the total cancer burden), making it the fifth most common malignancy in the world. GC represents a biologically and genetically diverse group of tumours with multifactorial aetiologies; both environmental and genetic. The vast majority of GCs are adenocarcinomas, which can be further subdivided into intestinal and diffuse histological subtypes according to the Lauren classification published in 1965. The molecular classification of GC according to the Cancer Genome Atlas (TCGA) divides GC into four subtypes: tumours positive for the EBV virus (9%), microsatellite unstable tumours (22%), genomically stable tumours (20%) and tumours with chromosomal instability (CIN) at 50%. Most GCs are sporadic by nature, where approximately 10% appear to possess a familial predisposition of which around half can be attributed to hereditary germline mutations i.e. those of the E-cadherin (CDH1) or mismatch repair (MMR) genes. Histopathological characteristics of the tumour type and analysis of potential genetic changes have substantial clinical significance, as they determine the choice of treatment. In this review, we consider the molecular pathogenesis, phenotype and testing of GC placing particular emphasis on microsatellite instability (MSI) and the CDH1 mutation

Generаl pаthomorphology

The manual presents the content and basic questions of the topic, practical skills in sufficient volume for each class to be mastered by students, algorithms for describing macro- and micropreparations, situational tasks. The formulation of tests, their number and variable level of difficulty, sufficient volume for each topic allows to recommend them as preparation for students to take the licensed integrated exam "STEP-1"

Diagnostic and therapeutic guidelines for gastro-entero-pancreatic neuroendocrine neoplasms (recommended by the Polish Network of Neuroendocrine Tumours)

W ostatnim czasie obserwuje się większe zainteresowanie rzadkimi nowotworami neuroendokrynnymi żołądkowo-jelitowo-trzustkowymi (GEP NEN). Wykrywalność nowotworów neuroendokrynnych w ostatnich latach wzrosła. Ponad 50% GEP NEN stanowią rakowiaki, które najczęściej są znajdowane przypadkowo podczas zabiegu operacyjnego w jelicie cienkim i w wyrostku robaczkowym oraz w momencie rozpoznania przerzutów odległych, głównie do wątroby. Istnieje konieczność współdziałania specjalistów różnych dziedzin medycyny w celu opracowania właściwych zasad postępowania diagnostyczno-leczniczego w tej grupie chorych. W niniejszej publikacji przedstawiono ogólne zalecenia Polskiej Sieci Guzów Neuroendokrynnych dotyczące postępowania u chorych z GEP NEN, opracowane podczas Konferencji, która odbyła się w Kamieniu Śląskim w kwietniu w 2013 roku. Członkowie grup roboczych zaktualizowali rekomendacje z 2008 roku.W kolejnych częściach tego opracowania przedstawiono zasady postępowania w:— nowotworach neuroendokrynnych żołądka i dwunastnicy (z uwzględnieniem gastrinoma);— nowotworach neuroendokrynnych trzustki; — nowotworach neuroendokrynnych jelita cienkiego i wyrostka robaczkowego;— nowotworach neuroendokrynnych jelita grubego.Zaproponowane rekomendacje przez ekspertów polskich i zagranicznych reprezentujących różne dziedziny medycyny (endokrynologię, gastroenterologię, chirurgię, onkologię, medycynę nuklearną i patomorfologię) powinny być pomocne w diagnostyce i leczeniu tych chorych. (Endokrynol Pol 2013; 64 (6): 418–443)An increased interest in gastro-entero-pancreatic neuroendocrine neoplasms (GEP NENs) has recently been observed. These are rare neoplasms and their detection in recent years has improved. Over 50% of GEP NENs are carcinoids, and they are usually found incidentally during surgery in the small intestine and appendix and at diagnosis in distant metastases, mainly to the liver. There is a need for co-operation between specialists in various disciplines of medicine in order to work out the diagnostic and therapeutic guidelines. In this publication, we present general recommendations of the Polish Network of Neuroendocrine Tumours for the management of patients with GEP NENs, developed at the Consensus Conference which took place in Kamień Śląski in April 2013. Members of the guidelines working groups were assigned sections of the 2008 guidance to update.In the subsequent parts of this publication, we present the rules of diagnostic and therapeutic management of:— neuroendocrine neoplasms of the stomach and duodenum (including gastrinoma);— pancreatic neuroendocrine neoplasms;— neuroendocrine neoplasms of the small intestine and the appendix;— colorectal neuroendocrine neoplasms.The proposed recommendations by Polish and foreign experts representing different fields of medicine (endocrinology, gastroenterology, surgery, oncology, nuclear medicine and pathology) will be helpful in the diagnosis and treatment of GEP NENs patients. (Endokrynol Pol 2013; 64 (6): 418–443

Clinicopathological features of extranodal lymphomas: Kuwait experience

A total of 935 patients with extranodal non-Hodgkin lymphoma (NHL) diagnosed in the period between January 1985 and December 2000 in Kuwait Cancer Center, serving the whole population of Kuwait, were used to describe the clinicopathological and epidemiological features of extranodal lymphomas in Kuwait. Extranodal lymphomas accounted for 45% of all NHL observed during this time. All NHL cases from Kuwait Cancer registry were analyzed and pathologically reclassified using the latest WHO ( 2000) classification. The most common lymphoma observed was diffuse large B-cell lymphoma (58.60%) followed by Burkitt's lymphoma (BL) (3.80%). In the pediatric group, BL comprises more than two thirds of all patients (77.20%). The most common extranodal sites were stomach (19.70%) and skin (17.80%) in the adult group, large intestine (29.80%) and small intestine (19.30%) in the pediatric age group. The majority (73.40%) of adult extranodal lymphomas was in stage IE - IIE and had a very good prognosis. On the contrary, the majority of pediatric extranodal lymphomas were found to be in stage III and IV. Variations in treatment policies ( single agent or combined chemotherapy, radiotherapy, combined modality treatment) adopted and changed during the time period of 16 years of this retrospective study were documented. Copyright (C) 2004 S. Karger AG, Basel

Gastric colonisation with a restricted commensal microbiota replicates the promotion of neoplastic lesions by diverse intestinal microbiota in the Helicobacter pylori INS-GAS mouse model of gastric carcinogenesis

Objectives: Gastric colonisation with intestinal flora (IF) has been shown to promote Helicobacter pylori (Hp)-associated gastric cancer. However, it is unknown if the mechanism involves colonisation with specific or diverse microbiota secondary to gastric atrophy. Design: Gastric colonisation with Altered Schaedler's flora (ASF) and Hp were correlated with pathology, immune responses and mRNA expression for proinflammatory and cancer-related genes in germ-free (GF), Hp monoassociated (mHp), restricted ASF (rASF; 3 species), and specific pathogen-free (complex IF), hypergastrinemic INS-GAS mice 7 months postinfection. Results: Male mice cocolonised with rASFHp or IFHp developed the most severe pathology. IFHp males had the highest inflammatory responses, and 40% developed invasive gastrointestinal intraepithelial neoplasia (GIN). Notably, rASFHp colonisation was highest in males and 23% developed invasive GIN with elevated expression of inflammatory biomarkers. Lesions were less severe in females and none developed GIN. Gastritis in male rASFHp mice was accompanied by decreased Clostridum species ASF356 and Bacteroides species ASF519 colonisation and an overgrowth of Lactobacillus murinus ASF361, supporting that inflammation-driven atrophy alters the gastric niche for GI commensals. Hp colonisation also elevated expression of IL-11 and cancer-related genes, Ptger4 and Tgf-β, further supporting that Hp infection accelerates gastric cancer development in INS-GAS mice. Conclusions: rASFHp colonisation was sufficient for GIN development in males, and lower GIN incidence in females was associated with lower inflammatory responses and gastric commensal and Hp colonisation. Colonisation efficiency of commensals appears more important than microbial diversity and lessens the probability that specific gastrointestinal pathogens are contributing to cancer risk.National Institutes of Health (U.S.) (grant R01 AI37750)National Institutes of Health (U.S.) (grant R01 CA093405)National Institutes of Health (U.S.) (grant P30-ES02109)National Institutes of Health (U.S.) (grant P01 CA028842)National Institutes of Health (U.S.) (grant T32 RR07036

Helminth co-infection in Helicobacter pylori infected INS-GAS mice attenuates gastric premalignant lesions of epithelial dysplasia and glandular atrophy and preserves colonization resistance of the stomach to lower bowel microbiota

Higher prevalence of helminth infections in Helicobacter pylori infected children was suggested to potentially lower the life-time risk for gastric adenocarcinoma. In rodent models, helminth co-infection does not reduce Helicobacter-induced inflammation but delays progression of pre-malignant gastric lesions. Because gastric cancer in INS-GAS mice is promoted by intestinal microflora, the impact of Heligmosomoides polygyrus co-infection on H. pylori-associated gastric lesions and microflora were evaluated. Male INS-GAS mice co-infected with H. pylori and H. polygyrus for 5 months were assessed for gastrointestinal lesions, inflammation-related mRNA expression, FoxP3[superscript +] cells, epithelial proliferation, and gastric colonization with H. pylori and Altered Schaedler Flora. Despite similar gastric inflammation and high levels of proinflammatory mRNA, helminth co-infection increased FoxP3[superscript +] cells in the corpus and reduced H. pylori-associated gastric atrophy (p < 0.04), dysplasia (p < 0.02) and prevented H. pylori-induced changes in the gastric flora (p < 0.05). This is the first evidence of helminth infection reducing H. pylori-induced gastric lesions while inhibiting changes in gastric flora, consistent with prior observations that gastric colonization with enteric microbiota accelerated gastric lesions in INS-GAS mice. Identifying how helminths reduce gastric premalignant lesions and impact bacterial colonization of the H. pylori infected stomach could lead to new treatment strategies to inhibit progression from chronic gastritis to cancer in humans.RO1-CA67529R01DK052413PO1CA26731P01 CA028842P30ESO2109R01DK06507