Osama Abdur Rehman, MD1, Shajetha Iyathurai, MD1, Fnu Aakash, MD1, Gautam Maddineni, MD1, Vivek Singh, MBBS2, Silpa Choday, MD3, Fnu Arti, MD4, Sunny Kumar, MD5, Aasta Kumari, MD6, Deepak Kumar, MBBS, MD7, Osama El Aryan, MD8, Ashwani Sethi, MD9 1Florida State University, Cape Coral, FL; 2FLORIDA STATE UNIVERSITY, Cape Coral, FL; 3Creighton University School of Medicine, Phoenix, AZ; 4Saint Francis Medical Center, Monroe, LA; 5Wright Center for Graduate Medical Education, Scranton, PA; 6North Central Bronx Hospital, New York, NY; 7Northwell Health, Port Jefferson, NY; 8Florida State Univeristy, Cape Coral, FL; 9Lee Health, Fort Myers, FL Introduction: Diffuse gastrointestinal polyposis is typically associated with hereditary syndromes such as familial adenomatous polyposis, Peutz-Jeghers syndrome, juvenile polyposis, and inflammatory conditions like pseudopolyps in inflammatory bowel disease. The malignant potential of these polyps varies by etiology. Rarely, diffuse polyposis can initially manifest an underlying extraintestinal malignancy. This report describes such a rare case where an asymptomatic patient was found to have mantle cell lymphoma (MCL) presenting as diffuse colonic and ileal polyposis.
Case Description/
Methods: A 70-year-old man with a medical history of hyperlipidemia and benign prostatic hyperplasia underwent a screening colonoscopy. He was completely asymptomatic, without abdominal symptoms, weight loss, or B symptoms. Endoscopic evaluation revealed diffuse, small, polypoid lesions from the rectum to the terminal ileum. The ileal mucosa appeared nodular, and the colonic mucosa showed generalized erythema and nodularity. Biopsies demonstrated an atypical, small-sized lymphoid infiltrate predominantly in the subepithelial layer. Immunohistochemical staining was positive for CD20 and BCL1 (cyclin D1), with a low Ki-67 proliferation index (~< 10%). CD3 highlighted scattered reactive T-cells. The findings were diagnostic for mantle cell lymphoma. PET-CT confirmed widespread nodal and extranodal involvement. The patient was referred to oncology and was started on systemic chemoimmunotherapy. Discussion: This case underscores the need for heightened awareness of lymphoma as a cause of diffuse gastrointestinal polyposis. Though primarily considered a systemic disease, Mantle cell lymphoma can present initially with isolated gastrointestinal findings. A hallmark endoscopic pattern of MCL is multiple lymphomatous polyposis (MLP)—numerous small polypoid lesions throughout the gastrointestinal tract. While this entity is well-described in literature, it remains underrecognized, especially in asymptomatic patients. This case illustrates the importance of considering lymphoproliferative disorders, particularly MCL, in the differential diagnosis when diffuse polyposis extending into the terminal ileum is encountered on routine colonoscopy, even without systemic symptoms.
Figure: Descending Colon as seen during colonoscopy
Figure: Ascending colon as seen during colonoscopy
Disclosures: Osama Abdur Rehman indicated no relevant financial relationships. Shajetha Iyathurai indicated no relevant financial relationships. Fnu Aakash indicated no relevant financial relationships. Gautam Maddineni indicated no relevant financial relationships. Vivek Singh indicated no relevant financial relationships. Silpa Choday indicated no relevant financial relationships. Fnu Arti indicated no relevant financial relationships. Sunny Kumar indicated no relevant financial relationships. Aasta Kumari indicated no relevant financial relationships. Deepak Kumar indicated no relevant financial relationships. Osama El Aryan indicated no relevant financial relationships. Ashwani Sethi indicated no relevant financial relationships.
Osama Abdur Rehman, MD1, Shajetha Iyathurai, MD1, Fnu Aakash, MD1, Gautam Maddineni, MD1, Vivek Singh, MBBS2, Silpa Choday, MD3, Fnu Arti, MD4, Sunny Kumar, MD5, Aasta Kumari, MD6, Deepak Kumar, MBBS, MD7, Osama El Aryan, MD8, Ashwani Sethi, MD9. P4694 - Under the Surface: Asymptomatic Mantle Cell Lymphoma Presenting as Diffuse Colonic Polyposis – A Case Report, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.
