Assessment of histologic disease activity in Crohn's disease: a systematic review.

Background: Crohn's disease (CD) is an idiopathic, chronic, transmural inflammatory disorder of the gastrointestinal tract. Because mucosal involvement is near-universal, endoscopic healing has emerged as an important aspect in improving outcome. However, resolution of histologic disease activity has potential to convey additional benefit beyond that attained with endoscopic healing alone.

Reactive lymphoid hyperplasia of the terminal ileum: a benign (lymphoma-like) condition that may harbor aberrant immunohistochemical patterns or clonal immunoglobulin heavy chain gene rearrangements.

Small endoscopic biopsies of the terminal ileum may be difficult to assess for early involvement by lymphoma. Immunophenotypic and genotypic analyses are often utilized, but the performance of these studies in this setting is not well defined. Terminal ileal biopsies from 66 patients with prominent lymphoid hyperplasia and abnormal "lymphoma-like" morphology were evaluated by immunohistochemistry (IHC) for CD3, CD5, CD43, CD20, CD21, and CD10 expression and for IGH@ gene rearrangement by polymerase chain reaction using BIOMED-2 primers.

Malignant pheochromocytoma presenting as incapacitating bony pain.

Among adrenal incidentalomas, pheochromocytomas are rare. Malignant pheochromocytoma is even less common, and it typically presents with classic hormonal symptoms, such as palpitations, labile blood pressures, and headaches. Bony metastasis usually occurs late in disease, but we report an unusual case of incapacitating bony pain as the initial presentation of malignant pheochromocytoma.

Histologic and molecular analyses of colonic perineurial-like proliferations in serrated polyps: perineurial-like stromal proliferations are seen in sessile serrated adenomas.

Colonic perineuriomas are recently described benign mucosal polyps that are composed of a bland spindle cell proliferation surrounding crypts that often demonstrate hyperplastic/serrated epithelial changes. However, the origin of this unique stromal proliferation is still unclear, and the association with serrated polyps, including sessile serrated adenomas, has not been fully described. We evaluated the pathologic and molecular features of colonic polyps associated with perineurial-like proliferations in 2 retrospective cohorts: (1) a series of 198 consecutive sessile serrated adenomas and (2) 20 colonic polyps diagnosed as a perineurioma irrespective of the presence of serrated colonic crypts.

HER2 expression in gastric and gastroesophageal junction adenocarcinoma in a US population: clinicopathologic analysis with proposed approach to HER2 assessment.

Recent evidence suggests that trastuzumab, a monoclonal antibody which targets HER2, in combination with chemotherapy is a therapeutic option in patients with HER2-positive gastric or gastroesophageal junction cancer. Widely accepted guidelines for HER2 testing in gastric and gastroesophageal junction cancer have not been established. The purpose of this study was to analyze the incidence and patterns of HER2 expression in gastric and gastroesophageal junction cancer using a tissue microarray approach, which closely simulates small biopsies routinely tested for HER2.

A two-antibody mismatch repair protein immunohistochemistry screening approach for colorectal carcinomas, skin sebaceous tumors, and gynecologic tract carcinomas.

Mismatch repair protein immunohistochemistry is a widely used method for detecting patients at risk for Lynch syndrome. Recent data suggest that a two-antibody panel approach using PMS2 and MSH6 is an effective screening protocol for colorectal carcinoma, but there are limited data concerning this approach for extraintestinal tumors. The purpose of this study was to review the utility of a two-antibody panel approach in colorectal carcinoma and extraintestinal tumors.