A Rare, Yet Treatable Pancreatic Tumor: Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma.

BACKGROUND Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) is a rare subtype of B-cell neoplasm that can have diverse presentations. When it involves the pancreas (i.e., pancreatic lymphoma), it can mimic metastatic pancreatic adenocarcinoma. Pancreatic lymphoma and adenocarcinoma often have similar clinical, laboratory, and radiographic features making the distinction challenging without pathological tissue examination. The differentiation of these 2 entities is important as the prognosis of pancreatic lymphoma is certainly more favorable with a chance of cure with chemoimmunotherapy. CASE REPORT We present an unusual case of EBV-positive DLBCL involving the pancreas that was initially believed to be metastatic pancreatic adenocarcinoma. The patient was treated with chemoimmunotherapy and had a remarkable response. This is the first known case of EBV-positive DLBCL involving the pancreas that was successfully treated with chemoimmunotherapy. CONCLUSIONS EBV-positive DLBCL can have diverse presentations, including a pancreatic mass with multi-organ involvement, which mimics metastatic pancreatic adenocarcinoma. The prognosis of EBV-positive DLBCL is thought to be worse than that of EBV-negative tumors. However, it remains certainly superior to that of its adenocarcinoma counterpart with conventional chemoimmunotherapy.