Periampullary Diffuse Large B-Cell Lymphoma Presenting as Acute Pancreatitis

Abstract

Periampullary malignancies are uncommon and encompass a wide variety of tumors. Early and accurate biopsy-proven diagnosis is important because different malignancy subtypes warrant different management and treatment plans. We present a unique and rare case of periampullary lymphoma, initially presenting as acute pancreatitis.

Keywords: acute pancreatitis; ampullary tumors; diffuse large B-cell lymphoma; periampullary lymphoma; tumor resection.

Figure 1.

Magnetic resonance imaging revealing enhancement of the ampulla bulging into the duodenum along with diffuse biliary and pancreatic ductal dilation.

Figure 2.

Endoscopic view of the large polypoid, ulcerated mass at the major duodenal papilla.

Figure 3.

(A) Endosonographic view of the periampullary mass invading into the pancreas and bile duct. (B) Endosonographic view of several round, heterogenous lymph nodes with well-defined margins in the porta hepatis region.

Figure 4.

Pathology slides of the biopsied ampullary mass revealed diffuse large B-cell lymphoma (germinal center B-cell subtype) based on morphological, immunophenotypical, and genetic findings. Small intestinal mucosa showed infiltrate of large atypical lymphocytes (A: Hematoxylin and Eosin (H&E), 100×; B: H&E, 400× magnification). By immunohistochemistry, these large atypical lymphocytes were positive for cluster of differentiation (CD) 20 (C: 200× magnification), B-cell leukemia/lymphoma (BCL6) (D: 200× magnification), CD10, and BCL2 with high proliferative index (Ki-67, 80%), but negative for CD5, multiple myeloma 1, BCL1, and myelocytoma (MYC). In situ hybridization for Epstein-Barr encoding region was negative, and no evidence of MYC, BCL2-immunoglobulin heavy chain, and BCL6 gene rearrangements was detected by fluorescent in situ hybridization.