Background: Extramedullary solitary plasmacytomas (EMD) are an uncommon manifestation of plasma cell disorders. The median survival rate is less than 6 months. EMD rarely involves the digestive tract, the liver is the most common site with only a 2.3% incidence rate for pancreatic involvement. Case Presentation: We report a case of a patient with a history of multiple myeloma who presented with painless obstructive jaundice and EUS findings of hypoechoic, solid irregular mass in the pancreatic head with surrounding peripancreatic lymphadenopathy. Fine needle aspirate (FNA) confirmed malignant infiltration of plasma cell neoplasm. The patient rapidly deteriorated and succumbed to his illness within 6 weeks of diagnosis.  Conclusion: Extramedullary plasmacytomas (EMD) involving the pancreas are uncommon and associated with a poor prognosis. Our case highlights the importance of considering extramedullary plasmacytoma when a patient with MM presents with a pancreatic mass, particularly one showing a rapid interval growth. This rate of growth is not seen with primary pancreatic parenchymal diseases such as cancer, cysts, and so on. This case highlights the importance of considering rare differentials while evaluating patients with pancreatic mass.

Keywords: Case report, extramedullary plasmacytoma, pancreatic plasmacytoma, multiple myeloma, pancreatic mass.