S3368 Rare Case of Extranodal Gallbladder Lymphoma Following Cholecystectomy

Introduction: Gallbladder cancer is a relatively rare malignancy making up approximately 50% of biliary tract malignancies. Even more exceedingly rare are gallbladder lymphomas making up just 0.1-0.2 percent of all gallbladder malignancies. This case demonstrates an incidental rare finding of gallbladder lymphoma following cholecystectomy. Case Description/Methods: A 72-year-old man presented with complaints of sudden onset of epigastric pain associated with nausea and vomiting. Lipase returned elevated at 3251. Magnetic resonance cholangiopancreatography (MRCP) was performed which demonstrated a dilated common bile duct concerning for gallstone pancreatitis. Patient underwent endoscopic ultrasound which demonstrated a 1.1 cm obstructing stone in the common bile duct, but endoscopic retrograde cholangiopancreatography (ERCP) scope was unable to be positioned appropriately. Subsequently, he underwent an elective cholecystectomy to prevent future episodes of choledocholithiasis. The final pathology of the gall-bladder-surprisingly demonstrated a marginal zone B cell lymphoma. Our patient then underwent Positron Emission Tomography (PET/computed tomography) scan as well as bone marrow biopsy for appropriate staging of disease. No other sites of increased activity were identified on PET/computed tomography and no evidence of lymphoproliferative neoplasm was noted in the bone marrow. Gallbladder Marginal Zone Lymphoma stage was determined to be 1E, and patient will be followed closely to assess for recurrence hereafter. Discussion: While some small case series have demonstrated a possible association between cholelithiasis and gallbladder lymphoma, establishing associations and etiology for the condition is difficult due to its rarity. Larger retrospective analyses in the future will better help to provide more evidence for establishing epidemiological factors associated with the disease as well as more concrete recommendations on surveillance following surgical excision.