Related Experiment Video
Updated: Aug 18, 2026

Flexible Colonoscopy in Mice to Evaluate the Severity of Colitis and Colorectal Tumors Using a Validated Endoscopic Scoring System
Published on: October 17, 2013
Implications of precancerous rectal biopsy in patients with inflammatory bowel disease
Abstract:
Sixty-five patients with an initial diagnosis of ulcerative colitis who underwent total proctocolectomy between 1955 and 1973 were studied retrospectively. Rectal mucosa in each patient was examined microscopically for the presence or absence of "precancerous" alterations as described by Morson and Pang. Histologic examination was made with no knowledge of concomitant colon carcinoma or the patients' clinical courses. Three of ten patients with precancerous rectal mucosa had invasive colon carcinoma, while none of the 55 patients without such changes had colon cancer (P less than .05, Fischer exact test). The duration of disease was significantly greater in those patients with rectal precancer (P less than .05). Reexamination changed the pathologic diagnosis in 15 patients from ulcerative colitis to granulomatous or "mixed" colitis. Two of three invasive cancers occurred in the reclassified group. Results support previous contentions that careful histologic evaluation of rectal biopsy specimens from individuals with inflammatory bowel disease may better define that population of patients with an increased risk of colonic carcinoma.
Related Concept Videos
Assessment of the Rectum and Anus
Rectal Inspection
Begin by inspecting the perianal and anal areas for color, texture, rashes,...
Inflammatory Bowel Disease I: Ulcerative Colitis
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
Inflammatory Bowel Disease II: Crohn's Disease
Inflammatory bowel disease, commonly known as IBD, refers to a collection of disorders that lead to persistent inflammation of the gastrointestinal tract. The two types of IBD are ulcerative colitis, which impacts the colon, and Crohn's disease, which can involve any part of the gastrointestinal segment.
Crohn's disease
Crohn's disease is a chronic, systemic inflammatory bowel disease (IBD) that predominantly affects the gastrointestinal tract. It is marked by transmural...
Inflammatory Bowel Disease III: Diagnostic Studies and Management I-Nutritional Therapy
Diagnostic studies
A colonoscopy is the definitive screening test, distinguishing ulcerative colitis from other colon diseases with similar symptoms. During a colonoscopy test, inflamed mucosa with exudate ulcerations can be observed, and biopsies are taken to determine the histologic characteristics of the colonic...
Inflammatory Bowel Disease I: Introduction
Inflammatory Bowel Disease IV: Clinical Manifestations

