Diagnostic Pitfall of Gastric Signet-Ring Cells: How to Diagnose a Benign Signet-Ring Cell From a Malignant One.

Sometimes non-neoplastic changes of the gastric mucosa mimic diffuse-type gastric carcinoma, specifically signet-ring cell adenocarcinoma. In fact, gastric epithelial cells undergoing signet-ring cell change have a cellular morphology that is almost identical to signet-ring cell adenocarcinoma, often leading to misdiagnosis. Accurate recognition of signet-ring cell change is essential to avoid overdiagnosis and overtreatment of signet-ring cell adenocarcinoma.

Clinical Performance of the Consensus Immunoscore in Colon Cancer in the Asian Population from the Multicenter International SITC Study.

BACKGROUND: In this study, we evaluated the prognostic value of Immunoscore in patients with stage I−III colon cancer (CC) in the Asian population. These patients were originally included in an international study led by the Society for Immunotherapy of Cancer (SITC) on 2681 patients with AJCC/UICC-TNM stages I−III CC. METHODS: CD3+ and cytotoxic CD8+ T-lymphocyte densities were quantified in the tumor and invasive margin by digital pathology.

Esophageal Melanocytosis: report of two cases and review of a rare and misunderstood entity.

Esophageal melanocytosis (EM) is a rare entity, which is characterized by a non-atypical melanocytic proliferation and melanin deposits in the esophageal mucosa. The confusion between the terms of melanosis and melanocytosis in the literature, the rarity of this lesion (less than 50 cases reported in the literature), its uncertain pathobiological course and the lack of experience of pathologists and gastroenterologists prompt us to draw the attention to this particular entity by reporting two cases and reviewing the literature. Magnifying endoscopy to observe intensive melanin accumulation followed by a biopsy are key for the diagnosis.

Randomized Phase 2 Study Comparing Pathological Responses of Resected Colorectal Cancer Metastases after Bevacizumab with mFOLFOX6 or FOLFIRI (BEV-ONCO Trial).

Retrospective studies reported that preoperative oxaliplatin-based chemotherapy increased pathological response (PR) in patients resected for colorectal liver metastases (CRLM). This multicenter prospective randomized (1/1) phase II trial evaluated PR on resected CRLM after preoperative mFOLFOX6 (arm A) or FOLFIRI (arm B) + bevacizumab. The primary endpoint was the major pathological response rate (MPRR), defined as the percentage of patients presenting CRLMs with mean tumor regression grade (TRG) < 3.

Sessile Serrated Lesion of the Appendix in a Teenage Girl.

According to the literature, serrated lesions and polyps of the appendix are extremely rare in children or teenagers. Herein, we present the pathologic and molecular features of a sessile serrated lesion (SSL) that was incidentally found in the appendix of a teenage girl. Our findings not only illustrate that appendiceal SSL may occur in young patients such as teenagers but also confirm further that V600E mutation may be found in a subset of these neoplastic lesions.

Prognostic assessment of resected colorectal liver metastases integrating pathological features, RAS mutation and Immunoscore.

Surgical resection of colorectal liver metastases combined with systemic treatment aims to maximize patient survival. However, recurrence rates are very high postsurgery. In order to assess patient prognosis after metastasis resection, we evaluated the main patho-molecular and immune parameters of all surgical specimens.

Multicenter International Society for Immunotherapy of Cancer Study of the Consensus Immunoscore for the Prediction of Survival and Response to Chemotherapy in Stage III Colon Cancer.

Purpose: The purpose of this study was to evaluate the prognostic value of Immunoscore in patients with stage III colon cancer (CC) and to analyze its association with the effect of chemotherapy on time to recurrence (TTR).

Methods: An international study led by the Society for Immunotherapy of Cancer evaluated the predefined consensus Immunoscore in 763 patients with American Joint Committee on Cancer/Union for International Cancer Control TNM stage III CC from cohort 1 (Canada/United States) and cohort 2 (Europe/Asia). CD3+ and cytotoxic CD8+ T lymphocyte densities were quantified in the tumor and invasive margin by digital pathology.

A Diagnostic Biopsy-Adapted Immunoscore Predicts Response to Neoadjuvant Treatment and Selects Patients with Rectal Cancer Eligible for a Watch-and-Wait Strategy.

Purpose: No biomarker to personalize treatment in locally advanced rectal cancer (LARC) is currently available. We assessed in LARC whether a diagnostic biopsy-adapted immunoscore (IS) could predict response to neoadjuvant treatment (nT) and better define patients eligible to an organ preservation strategy ("Watch-and-Wait").

Experimental Design: Biopsies from two independent cohorts ( = 131, = 118) of patients with LARC treated with nT followed by radical surgery were immunostained for CD3 and CD8 T cells and quantified by digital pathology to determine IS.

Guidelines for an optimal management of a malignant colorectal polyp. What is essential in a pathology report ?

Colorectal cancer (CRC) has become the most common malignancy in our country. Routine screening colonoscopy is on the rise. With the recent advances in endoscopic treatment, many T1 colorectal carcinomas are now found and their percentage amenable to endoscopic resection has increased.

Combined excision and ablation of ampullary tumors with biliary or pancreatic intraductal extension is effective even in malignant neoplasms.

Background: The feasibility and outcome of endoscopic resection in ampullary tumors with intraductal growth remains unclear.

Objective: To assess the safety, feasibility and outcomes of these patients treated by thermal ablation.

Methods: Retrospective observational study.

[An unusual case of olmesartan induced enteropathy].

Olmesartan induced enteropathy was first described in 2012. It is a rare adverse effect of this antihypertensive drug. The clinical presentation commonly includes severe chronic diarrhea leading to weight loss and a variable degree of dehydration.

The Link between the Multiverse of Immune Microenvironments in Metastases and the Survival of Colorectal Cancer Patients.

Treatment of metastatic colorectal cancer is based upon the assumption that metastases are homogeneous within a patient. We quantified immune cell types of 603 whole-slide metastases and primary colorectal tumors from 222 patients. Primary lesions, and synchronous and metachronous metastases, had a heterogeneous immune infiltrate and mutational diversity.

Mucin-producing hepatic cystic neoplasms: an uncommon but challenging disease often misdiagnosed and mismanaged.

Mucin-producing hepatic cystic neoplasms (MHCN) are uncommon and potentially malignant. Nine MHCN were encountered in our centre for over 32 years. Patients' clinical, biological, radiological and pathological features were reviewed.

The role of the pathologist and clinical implications in colorectal liver metastasis.

Colorectal liver metastases (CRLM) affect about 50% of colorectal cancer patients. With the improvement of neoadjuvant chemotherapy and the introduction of targeted therapy, resectability of CRLM and survival rates have improved over time. However, 60-70% of patients still recur.

Evolution of Metastases in Space and Time under Immune Selection.

We examined how the immune microenvironment molds tumor evolution at different metastatic organs in a longitudinal dataset of colorectal cancer. Through multiplexed analyses, we showed that clonal evolution patterns during metastatic progression depend on the immune contexture at the metastatic site. Genetic evidence of neoantigen depletion was observed in the sites with high Immunoscore and spatial proximity between Ki67 tumor cells and CD3 cells.

Risk factors for conversion to snare resection during colorectal endoscopic submucosal dissection in an expert Western center.

Background: There are limited data regarding the risk factors and consequences of conversion to endoscopic mucosal resection (rescue EMR) during colorectal endoscopic submucosal dissection (ESD) in Western centers.

Methods: This was a retrospective analysis of a prospectively collected database, from which 225 consecutive ESDs performed between 2013 and 2017 were selected. Of the included patients, 39 (18.

Comparative analysis of ESD versus EMR in a large European series of non-ampullary superficial duodenal tumors.

Background And Study Aims: The choice of endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) in non-ampullary superficial duodenal tumors (NASDTs) is challenging and the benefits of ESD remain unclear. The aim was to comparatively analyze the feasibility, outcomes and safety of these techniques in these lesions.

Patients And Methods:  This is an observational and retrospective study.

ESD versus EMR in non-ampullary superficial duodenal tumors: a systematic review and meta-analysis.

Background And Study Aims:  Endoscopic submucosal dissection (ESD) has been developed as an option for treatment of esophageal, gastric and colorectal lesions. However, there is no consensus on the role of ESD in duodenal tumors.

Methods:  This systematic review and meta-analysis compared ESD and endoscopic mucosal resection (EMR) in sporadic non-ampullary superficial duodenal tumors (NASDTs), including local experience.

A case of unusual histiocytic colitis in a chronic alcoholic obese patient with ankylosing spondylitis.

A 64 year-old Caucasian man was first investigated 21 years ago for persistent diarrhoea. A colonoscopy revealed an erosive pancolitis with unusual vacuolated macrophages. Characteristics of ulcerative colitis or Crohn's disease were absent.

International validation of the consensus Immunoscore for the classification of colon cancer: a prognostic and accuracy study.

Background: The estimation of risk of recurrence for patients with colon carcinoma must be improved. A robust immune score quantification is needed to introduce immune parameters into cancer classification. The aim of the study was to assess the prognostic value of total tumour-infiltrating T-cell counts and cytotoxic tumour-infiltrating T-cells counts with the consensus Immunoscore assay in patients with stage I-III colon cancer.

Evaluation of the correlation between mutated allele frequency and pathologist tumorous nuclei percentage assessment in colorectal cancer suggests a role for zygosity status.

Evaluation of molecular tumour heterogeneity relies on the tumorous nuclei percentage (TNP) assessment by a pathologist, which has been criticised for being inaccurate and suffering from interobserver variability. Based on the 'Big Bang theory' which states that mutation in colorectal cancer is mostly homogeneous, we investigated this issue by performing a critical analysis of the correlation of the mutant allele fraction with the TNP in 99 colorectal tumour samples with a positive mutation status as determined by next-generation sequencing. Our results yield indirect evidence that the KRAS zygosity status influences the correlation between these parameters and we show that a well-trained pathologist is indeed capable of accurately assessing TNP.

Dysplasia in inflammatory bowel disease.

Ulcerative colitis and Crohn's diseases are relapsing longstanding inflammatory bowel diseases, associated with an increased risk of developing colorectal cancer. Continuous surveillance is necessary to detect the preneoplastic lesions in an early stage. New endoscopic techniques have improved the diagnostic accuracy and have resulted in a new and more simplified classification system of the dysplastic lesions in the bowel.