Osseous metaplasia in a rectal polyp

Rectal polyps are finger-like projections of the mucosal surface that generally present with complaints of bleeding or mass per rectum. Polyps are classified histopathologically as neoplastic and non-neoplastic. Here, we present one such rare case of a middle-childhood boy who presented with complaints of bleeding per-rectum and revealed a 1.5 cm long rectal polyp. Histopathological examination revealed an osseous change in the rectal polyp. A detailed literature review of reported cases of benign rectal polyps with osseous metaplasia was conducted and consolidated all postulated theories of pathogenesis. This case report shows an interesting incidental finding of osseous metaplasia of the rectal polyp.

Incidental morphological findings in colorectal adenomas

Owing to a sharp increase in the frequency of diagnosis of colorectal adenomas in the current era of population screening, distinctive morphological features are increasingly being observed. These may present diagnostic challenges and cause clinical management issues. Paneth cell metaplasia is a more common occurrence, but the incidence rates of squamous metaplasia, clear cell metaplasia, osseous metaplasia, neuroendocrine differentiation and signet‐ring cell‐like lesion are low, and they can be seen in <1% of colorectal adenomas. Their histomorphological characteristics are quite unique; ancillary studies are not very helpful and often not needed. In this review, we give an overview and describe the potential clinical consequences of such incidental and special morphological findings in colorectal adenomas.