A Case Report of Primary Diffuse Large B-Cell Lymphoma of the Gallbladder in the form of a Polyp in a 50-Year-Old Man at Imam Khomeini Hospital, University of Tehran

Abstract

Primary gallbladder lymphoma (PGL) is an extremely rare malignancy, with diffuse large B-cell lymphoma (DLBCL) being a common subtype. We report a case of a 50-year-old man presenting with vague right upper quadrant abdominal pain, without a history of fever, sweating, or weight loss. Initially suspected to have gallbladder adenocarcinoma based on imaging findings, the patient underwent extensive diagnostic evaluation and surgery. An extended cholecystectomy was performed. Histopathological examination confirmed diffuse large B-cell lymphoma, not otherwise specified (NOS), of the germinal center B-cell (GCB) subtype, with infiltration up to the serosal layer but no involvement of the liver parenchyma. This case highlights the diagnostic challenges of primary gallbladder lymphoma and the critical role of histopathological evaluation in unusual gallbladder masses.