Polyps and Tumour‐Like Lesions of the Large Intestine

Familial adenomatous polyposis: a review of gastrointestinal manifestations

“…33 Flat adenomas and serrated adenomas are also rarely seen. 31 Notably, no distinguishing microscopic features are seen in adenomas or adenocarcinoma arising in FAP compared to their sporadic counterparts (Figure 3). …”

“…30 Unicryptal adenoma is the pathognomonic lesion in FAP, originally described microscopically but which can now be identified by chromoendoscopy. 31 It has been reported that small polyps (<3 mm in size) are not observed after barium enema, resulting in underestimation of the number of polyps. 32 Pathologic findings: as described earlier, classic FAP individuals have >100 adenomas, a number selected because all FAP individuals in the St. Mark's registry had polyp counts ranging from 104 to greater than 5000 with a mean of 1000.…”

Challenging diagnostic issues in adenomatous polyps with epithelial misplacement in bowel cancer screening: 5 years’ experience of the Bowel Cancer Screening Programme Expert Board

“…Given the NHS experience of cancer screening, relatively strict quality assurance procedures were put in place, with a specific BCSP External Quality Assurance (EQA) scheme, but few would have anticipated the major diagnostic issues faced by BCSP pathologists. The major pathological challenges were, and are, the biopsy diagnosis of colorectal cancer, serrated polyp pathology, the diagnosis and management of polyp cancer, and, finally, epithelial misplacement in adenomatous polyps, especially of the sigmoid colon …”

“…The major pathological challenges were, and are, the biopsy diagnosis of colorectal cancer, serrated polyp pathology, the diagnosis and management of polyp cancer, and, finally, epithelial misplacement in adenomatous polyps, especially of the sigmoid colon. [6][7][8] There is no doubt that the challenges caused by epithelial misplacement in adenomatous polyps of the sigmoid colon have proved the most difficult in terms of pathological diagnosis in the BCSP. 9 In particular, such adenomatous polyps, because of the narrowness of the sigmoid colon and its motility, and the association with diverticular disease (or, at least, pre-diverticular disease) in the majority of patients of this age, are subject to pronounced mechanical trauma and this accounts for the high frequency of mucosal prolapse changes and epithelial misplacement that characterises these polyps.…”

The pathology of hereditary polyposis syndromes

“…As our understanding of the genetics of familial colorectal cancer syndromes has improved it has become apparent that there is phenotypic overlap between many of the syndromes. The aim of this paper is not to describe the histopathology of intestinal polyps, which is covered extensively elsewhere, but to outline our current understanding of the inheritance, genetics and clinical features of colorectal cancer syndromes (see Table ).…”