Pancreatic malignancies are common, accounting for 15% of cancer patients in the United States. As 85% of pancreatic malignancies comprise of adenocarcinoma, physicians are generally less familiar with other types of pancreatic neoplasms. Here we report a case of anaplastic large cell lymphoma (ALCL), a rare subtype of non-Hodgkin's lymphoma, and one of the subtypes of T-cell lymphoma, presenting as a pancreatic mass causing acute pancreatitis. Recognition of ALCL is important as the disease is highly sensitive to chemotherapy, and thus carries a very good prognosis. A 64-year-old female presented to the emergency department with one week of abdominal pain and nausea. Physical exam revealed RUQ abdominal tenderness. Labs were significant for ALT 271 U/L, AST 234 U/L, ALP 706 U/L, total bilirubin 2.5 mg/dL, and lipase 115 U/L. A CT demonstrated pancreatic head edema with a poorly defined area of hypo-enhancement within the head. An MR showed a 1.5 cm stricture in the mid-distal CBD, as well as a 16 mm area of increased signal focus concerning for possible mass or pancreatitis in the pancreatic head. An EGD was performed, which revealed a 5 mm gastric body polyp with superficial erosion. An EUS revealed a 20 mm hypoechoic pancreatic head mass with invasion in the mid-CBD and the portal vein. Biopsies from the gastric body polyp and pancreatic head mass resulted as anaplastic lymphoma kinase (ALK)-positive ALCL. Patient underwent an ERCP for biliary decompression. The patient was started on CHOP with pegfilgrastim with good response. Our case of ALK-positive ALCL was unique in several aspects. First, ALK-positive ALCL usually affects children and young adults, while patients above the age of 55 typically present with ALK-negative ALCL. Second, patients with ALCL typically have B symptoms, but our patient presented with acute pancreatitis and obstructive jaundice. Third, contrary to ALCL's typical extranodal involvement of skin and bone, our patient had primary pancreatic and gastric involvement, which is exceedingly rare. To our knowledge, fewer than 10 cases of pancreatic ALCL have been reported. Overall, the prognosis of ALK-positive ALCL is considerably better, with a 5-year overall survival ranging from 70-90%, compared to 40-60% for ALK-negative ALCL. Patients with ALK-positive disease usually respond very well to CHOP. Patients with ALK-negative disease sometimes will require higher doses of chemotherapy followed by stem cell transplantation.1450_A.tif Figure 1: A gastric polyp was seen during EGD which was positive for ALK-positive anaplastic large cell lymphoma.1450_B.tif Figure 2: The pancreatic ALCL was seen invading the portal vein and the mid common bile duct on EUS1450_C.tif Figure 3: ALK-positive anaplastic large cell lymphoma involving the stomach and pancreas. (A) H+E stain; (B) CD-30 positive stain; (C) ALK positive stain