Diffuse Large B cell Lymphoma presenting as Acute Pancreatitis

Background: Diffuse large B cell Lymphoma (DLBCL), not otherwise specified (NOS) is the most common type of lymphoma in the world accounting for 25–30% of Non-Hodgkin lymphomas (NHL). It is more common in the elderly but occurs in all age groups and predominantly affect the male.Most common sites of involvement include lymph nodes or extranodal sites (bone, skin, thyroid, gastrointestinal tract and lung).1 Only 1.25% to 2.2% of all patients with NHL have pancreatic involvement at presentation.2,3 Primary pancreatic lymphoma (PPL) rarely presents with the typical B symptoms observed in lymphoma (ie, weight loss, fever, or night sweats).4–6 Here we report an unusual and rare case of PPL which was first diagnosed as acute biliary pancreatitis that was later found to be Pancreatic Adenocarcinoma and later confirmed on biopsy as DLBCL-NOS. Case Report: An 80-years-old caucasian male presented to the ER with complaints of abdominal pain for one day, generalized weakness and shortness of breath for two weeks. ROS otherwise unremarkable. Vitals showed elevated blood pressure otherwise unremarkable. Physical exam was positive for epigastric tenderness radiating to the back without any signs of peritonitis and labs showed TBili-5.4, DBili-3.6, AST-440, ALT-502, AlkPhos-372, LDH-388, Amylase-268, Lipase-4403. Beta-2-microglobulin-2.4, AFP-1.5, CEA-0.7, CA 19-9-178. Patient had a prior history of Prostate CA status-post radiation. CT Abdomen showing a pancreatic mass with biliary and duodenal obstruction suggestive of a tumor. CT Abdomen and pelvis with contrast was suggestive of Pancreatic Adenocarcinoma. Patient was diagnosed with acute biliary pancreatitis and was started IVF and pain medication. He subsequently underwent placement with a biliary drain to relieve obstruction. Biopsy was suggestive of DLBCL-NOS. Patient was started on CHOP-R regimen and advised to have a close follow up with oncologist as an outpatient. As treatment progresses, biliary drain will be replaced by indwelling stents to relieve the obstructions. Discussion: PPL is a rare neoplasm that can mimic pancreatic adenocarcinoma in many aspects. Arriving to a proper diagnosis using both biochemical and tissue biopsy is very essential as it carries excellent prognosis if diagnosed early. The best therapeutic option as per the study by Behrns et al and many other recent studies is chemotherapy CHOP-R with or without surgical resection and radiotherapy depending on the Ann Arbor staging and is associated with increased long-term survival of PPL.7-8