Cancer of Unknown Primary With Presumptive Pancreatic Cancer Treated With FOLFIRINOX.

A 52-year-old man was found to have an increase in carbohydrate antigen (CA)19-9. He underwent endoscopic ultrasound/fine needle aspiration (EUS-FNA) of the soft tissue shadow near the pancreas and was diagnosed with adenocarcinoma. The cancer was judged to be of unknown primary.