Peutz-Jeghers syndrome: a critical look at colonic Peutz-Jeghers polyps

• Published in: Modern pathology 2013-09, Vol.26 (9), p.1235-1240
• Main Authors: Tse, Julie Y, Wu, Shulin, Shinagare, Shweta A, Lauwers, Gregory Y, Yilmaz, Omer, Wu, Chin-Lee, Deshpande, Vikram
• Format: Article
• Language: English
• Subjects: 692/699/1503/1581/1392; 692/700/139/422; Adult; Biomarkers, Tumor - analysis; Cancer; Case-Control Studies; Colonic Neoplasms - chemistry; Colonic Neoplasms - pathology; Colonic Polyps - chemistry; Colonic Polyps - pathology; Desmin - analysis; Diagnosis, Differential; Family medical history; Female; Humans; Immunohistochemistry; Intestinal Mucosa - chemistry; Intestinal Mucosa - pathology; Intestine, Small - chemistry; Intestine, Small - pathology; Kinases; Laboratory Medicine; Male; Medicine; Medicine & Public Health; Morphology; Muscle, Smooth - chemistry; Muscle, Smooth - pathology; Mutation; original-article; Pathology; Patients; Peutz-Jeghers Syndrome - metabolism; Peutz-Jeghers Syndrome - pathology; Polyps; Predictive Value of Tests; Smooth muscle; Tumors; Young Adult
• ISSN: 0893-3952; 1530-0285
• DOI: 10.1038/modpathol.2013.44

Peutz-Jeghers syndrome is an autosomal dominant condition characterized by gastrointestinal hamartomatous polyps. The pathologic identification of a Peutz-Jeghers polyp is integral to the diagnosis of this syndrome that often remains undiagnosed until after these polyps are identified. Histologically, Peutz-Jeghers polyps are characterized by a distinctive arborization of smooth muscle within the lamina propria. Colonic Peutz-Jeghers polyps, however, may mimic mucosal prolapse polyps or virtually any colonic polyp that undergoes prolapse. In this paper, we explore the morphological features of colonic Peutz-Jeghers polyps and the diagnostic challenges associated with these polyps. Colonic polyps from patients with Peutz-Jeghers syndrome were identified ( n =34). The control cohort, included mucosal prolapse polyps ( n =5), hyperplastic polyps ( n =10) and tubular adenomas with prolapse ( n =9), ganglioneuromatous polyps ( n =2) and juvenile polyps ( n =14). Intramucosal smooth muscle fibers were identified in all classes of polyps. Twenty-three of the 34 colonic Peutz-Jeghers polyps were characterized by lobulated clusters of colonic crypts. On immunohistochemistry, desmin-positive smooth muscle fibers were seen surrounding these lobules. This lobular organization of the crypts was not identified in mucosal prolapse polyps and hyperplastic polyps or tubular adenomas with prolapse; only one of the 14 juvenile polyps showed this pattern of reactivity on a desmin stain. Our data suggests that the histologic hallmark of colonic Peutz-Jeghers polyps is the lobular organization of the crypts, and that an arborizing pattern of smooth muscle proliferation is neither sensitive nor a specific marker of colonic Peutz-Jeghers polyps. The presence of desmin-positive smooth muscle fibers surrounding the lobules is a helpful diagnostic feature of colonic Peutz-Jeghers polyps, and facilitates the distinction of these polyps from non-Peutz-Jeghers polyps with prolapse-like changes.