Primary Mantle Cell Lymphoma of the Colon

Abstract

Background: Mantle cell lymphoma (MCL) is an aggressive type of B-cell Non-Hodgkin lymphoma that originates from small to medium sized lymphocytes located in the mantle zone of the lymph node. Extra nodal involvement is present in the majority of cases, with a peculiar tendency to invade the gastrointestinal tract in the form of multiple lymphomatous polyposis. It has a reported frequency of between 4-9% of all gastrointestinal B-cell MCLs can be accurately diagnosed with the use of the highly specific marker Cyclin D1. The number of cases reported of primary mantle cell lymphoma of the GI tract is very limited, and even rarer in the colon. Here we present a case of primary malignant multifocal polypoid mantle cell lymphoma of the colon presenting with periumbilical pain. Case presentation: A 75-year-old female with a history of hypertension and renal artery stenosis who presented with abdominal pain worsening constipation and decreased appetite over the course of a week. She had a colonoscopy five years ago that showed a tubular adenoma in the cecum and diverticulosis. Exam showed some mild periumbilical tenderness. Colonoscopy revealed multiple atypical appearing polypoid mass lesions in the sigmoid, descending and transverse colon. The largest lesion was in rectum and had an umbilicated center. It measured 3 cm in size. Biopsies of the lesions showed primary malignant mantle cell lymphoma. The histology and immuno-histochemistry revealed prominent lymphoid infiltrate, involving the lamina propria and focally into the submucosa with positivity to CD20 B cells with co-expression of Cyclin D1 marker and CD5. The patient is currently doing well on her third cycle of VR-CAP (Bortezomib plus Rituximab, Cyclophosphamide, Doxorubicin and Prednisone) therapy.Figure 1Figure 2Figure 3Conclusion: This is a rare case of primary multifocal colonic mantle cell lymphoma presenting with constipation, abdominal pain and a relatively recent benign colonoscopy. Our case highlights the fact that this rare cancer can present with little specific physical findings and the polyps have an atypical polypoid fleshy multifocal appearance. It also highlights the importance of pattern recognition and differentiation from other polypoid lesions during colonoscopy.