Introduction Epithelial neoplasms develop far less frequently in the small intestine than in the colon, despite the fact that the small intestine has a larger epithelial surface area and a higher rate of cellular turnover. Overall, only 2% of all…
Introduction Gastric cancer remains an important cancer worldwide and is responsible for over 1 million new cases in 2020, and an estimated 769,000 deaths (equating to 1 in 13 deaths globally), ranking fifth for incidence and fourth for mortality globally.…
Introduction Most benign and malignant neoplasms of the esophagus are epithelial in origin ( Box 24.1 ). Overall, an estimated 17,650 new diagnoses of esophageal carcinoma, and 16,000 deaths, occurred in the United States in 2019. The incidence of esophageal…
Introduction The genomic revolution is inexorably changing our understanding of nearly all medical conditions, and it is changing our clinical practices in the fields of diagnostic pathology and oncology. Indeed, genomic biomarkers have dramatically improved clinical algorithms for diagnosis, prognosis,…
Introduction Large bowel screening programs have been shown to substantially reduce the incidence of colorectal carcinoma by identifying and removing premalignant polyps. Increased use of colonoscopy has led to an increase in the number of polyps encountered in daily pathology…
Introduction Upper gastrointestinal (GI) endoscopy is routinely performed as part of the evaluation of patients with GI symptoms. Newer techniques such as double-balloon enteroscopy and capsule endoscopy also allow for complete visualization of the small intestine. Gastroenterologists may identify and…
Introduction Gastric polyps are identified in up to 6.3% upper gastrointestinal (GI) endoscopic procedures. They may develop as a result of epithelial or stromal cell hyperplasia, inflammation, ectopia, or neoplasia. This chapter classifies gastric polyps according to the predominant cell…
Introduction Most types of inflammatory lesions of the esophagus do not manifest as endoscopically recognizable polyps. They instead cause only a slight mucosal irregularity or surface erosion. In contrast, most neoplastic processes of the esophagus manifest clinically at an advanced…
Introduction The appendix is a vestigial organ without proven significant physiological function; however, it is subject to a host of clinically significant inflammatory disorders, some of which involve the appendix exclusively and others that are systemic. The vermiform appendix arises…
Approach To Evaluating Colitis Pathologists are asked to evaluate colorectal biopsy specimens for a variety of reasons, but often only a pattern of injury can be identified, at best. This evaluation is performed with the hope that a specific diagnosis…