# Colonic lymphomatous polyposis mantle cell lymphoma: a case report and review of literature

## TL;DR

This case report describes a rare form of mantle cell lymphoma presenting as colonic lymphomatous polyposis in a 56-year-old man.

## Contribution

The novelty lies in the detailed clinical and histopathological presentation of a rare gastrointestinal lymphoma variant.

## Key findings

- The patient exhibited multiple colonic polyps confirmed as mantle cell lymphoma via immunohistochemistry.
- The tumor cells expressed CD20, CD5, Bcl2, and cyclin D1 but lacked CD10 and CD23 expression.
- Lymphomatous polyposis was diagnosed with a Ki67 proliferation index of 25%.

## Abstract

Mantle cell lymphoma is a rare lymphoma of the gastrointestinal tract that may present as multiple lymphomatous polyposis. We report a case of lymphomatous polyposis with a review of the literature.

A 56-year-old man of Black ethnicity and Ivorian nationality with no relevant past medical history, consulted for a sudden onset symptoms of gastrointestinal obstruction, which evolved over 2 days. Macroscopic examination revealed the presence of multiple polyploid formations of the colonic mucosa. Histology showed diffuse lymphomatous proliferation of submucosa consisting off small lymphoid cells with a hyperchromatic crenelated nucleus, suggesting lymphomatous polyposis. Immunohistochemical examination showed expression by the tumor cells of antibodies to CD20, CD5, Bcl2, and cyclin D1. They did not express antibodies to CD10 and CD23. The Ki67 proliferation index was 25%. We have thus retained the diagnosis of mantle cell lymphomatous polyposis.

Multiple lymphomatous polyposis is a rare entity characterized by the presence of numerous gastrointestinal polyploid lesions sometimes involving several segments of the gastrointestinal tract. Typical lymphoma presenting as lymphomatous polyposis is mantle cell lymphoma; although, other tumors may have this aspect.