Benign fibroblastic polyp of the colon: A case report

Polypoid lesions of the gastrointestinal (GI) tract are common and divergent. Most of the polyps are epithelial in origin but polypoid mesenchymal proliferations and inflammatory lesions are also encountered. Although most of the polyps, especially those with epithelial features, can be diagnosed accurately, there are some polyps that cannot be classified easily under a certain category. This particularly applies to mesenchymal cell proliferations in most of the cases. Benign fibroblastic polyp of the colon (BFPC) is a distinctive type of mucosal polyp of the colorectum described by Eslami-Varzaneh et al. in 2004 (1). It is composed of benign-appearing spindle cells in the lamina propria leading to a wide separation and disorganization of the colonic crypts. We are aware of 32 cases reported to date under the proposed terminology (2-4). Most of the cases were located in the sigmoid colon (1, 3). Patients are generally asymptomatic or have a history of mild rectal bleeding (2). Almost all lesions were detected on routine screening colonoscopy but were identified as nonspecific “polyps” (1). They are small lesions measuring 0.2 cm to 1.5 cm (1, 3). They are solitary polyps but accompanied by various lesions, mainly tubular adenoma, hyperplastic polyps or diverticulosis (14). BFPC is morphologically and immunohistochemically distinct from other mesenchymal polyps and appears to be relatively rare, constituting about 0.2-1.5% of all colonic polyps according to the previous reports (1, 4). BFPC follows an indolent course. None of the reported cases recurred during a maximum follow-up period of 36 months (mean: 18 months) (2). We present a case interpreted as BFPC and discuss it together with the differential diagnostic considerations.