1423 Primary B-Cell Pancreatic Lymphoma Presenting as Acute Pancreatitis

Abstract

INTRODUCTION: Primary pancreatic lymphoma (PLL) is a very rare type of pancreatic malignancy and accounts for less than 1% of all pancreatic masses. Presenting symptoms are non-specific and may lead to delay in diagnosis. CASE DESCRIPTION/METHODS: A 71-year-old man with diabetes mellitus and hypertension presented to hospital with epigastric pain, nausea, and vomiting for 3 days. He had loss of appetite and weight loss for 2 months. On physical examination, his vital signs were normal, and he had tenderness on palpation at epigastric area without signs of peritonitis. Complete blood counts were within normal limits. He had transaminitis and elevated total bilirubin and alkaline phosphatase. Serum amylase and lipase were 123 IU/L (normal: 13-53) and 864 IU/L (normal: 13-60), respectively. Tumor markers, including CA 19.9 and CEA, were normal. Magnetic resonance imaging (MRI) of the pancreas showed a large mass at the pancreatic head measuring 8.3 × 7.6 cm in maximum diameter with peripancreatic and retroperitoneal adenopathy (Figure 1). Endoscopic ultrasound demonstrated the mass in the pancreatic head and malignant-appearing peripancreatic lymph nodes. Computer tomography (CT) guided biopsy of the pancreatic mass was performed. Pathology revealed a high grade B-Cell Lymphoma. Bone marrow biopsy did not show atypical cells. Staging CT scans revealed a 9 mm sized mediastinal node. He was diagnosed with stage III high grade B-Cell primary pancreatic lymphoma. An International Prognostic Index was 2 which predicts a 5-year survival of 51%. He received R-CHOP regimen for treatment and currently on cycle 5 with a good response. DISCUSSION: Primary pancreatic lymphoma is a rare malignancy accounting for 0.7% of all pancreatic malignancies and 1% of extranodal lymphomas. The disease is male predominant about 7 times more frequent than in females.2 Non-specific gastrointestinal symptoms are the most common presentations, including abdominal pain, obstructive jaundice, or acute pancreatitis. Imaging of the pancreas by MRI or CT scan may help to distinguish PPL from the more common pancreatic adenocarcinoma. However, cytohistology of the mass is required for diagnosis and to guide definitive treatment. Surgery has a limited role in management, and chemotherapy is the main treatment.