Introduction: Marginal zone B-cell lymphoma is an indolent type of Non-Hodgkin’s lymphoma classified into Extranodal marginal zone lymphoma of mucosal-associated lymphoid tissue (MALT), nodal marginal zone lymphoma, and splenic marginal zone lymphoma. Nodal marginal zone lymphoma is one of the rarest NHL and accounts for less than one percent of cases.
Case Description/Methods: A 65-year-old male with a history of coronary artery disease, COPD, essential hypertension, hyperlipidemia, ITP underwent a screening colonoscopy at the gastroenterology clinic. A colonoscopic finding of an area of congested mucosa with abnormal vascular pattern in the rectum localized at 20 cm, concerning for pseudopolyp was biopsied. The patient underwent CT pelvis with contrast which was significant for marked eccentric rectal wall thickening with retroperitoneal lymphadenopathy highly suspicious for malignancy. Pathological examination of the biopsy showed colonic mucosa with prominent lymphoid aggregates. Immunohistochemical staining revealed abundant PAX5 positive B-cells in a background of T-cells highlighted by CD3 but negative for CD5, CD10, CD43, cyclin D1. The morphology, together with B cell gene rearrangement, supports the diagnosis of marginal zone B cell lymphoma. PETCT scan from skull base to mid-thigh revealed hypermetabolic rectal wall thickening, retroperitoneal and bilateral iliac lymphadenopathy. The patient is currently undergoing follow-up at the hematology clinic.
Discussion: The absence of clinical symptoms and the diagnosis in a routine screening colonoscopy makes this case rare. Even though there is extranodal involvement in the rectum, since the patient has the involvement of the retroperitoneal and bilateral iliac lymph nodes, classify it as a nodal marginal zone lymphoma. Treatment aims at improving quality of life, alleviating symptoms, and reversing the cytopenias. Asymptomatic patients do not need immediate therapy but need to be monitored closely to develop symptoms and progression of the disease.
Jemin Jose indicated no relevant financial relationships.
Tapasya Raavi indicated no relevant financial relationships.
Insija Selene indicated no relevant financial relationships.
Bilal Gondal indicated no relevant financial relationships.
Jemin Jose, MBBS1, Tapasya Raavi, MBBS, MPH1, Insija Selene, MBBS2, Bilal Gondal, MBBCh1. P0284 - Incidental Lymphoma, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.