Clinically, the most important differential diagnosis is chronic pancreatitis. However, pancreatic cancer cannot always be differentiated from pancreatitis, even by laparotomy. If cancer cannot be excluded and the patient is operable, work-up and treatment should be as if cancer is present.
Cancer in adjacent organs
Cancer in the Ampulla of Vater, duodenal cancer, and distal (intrapancreatic) cancer of the common bile duct cancer, have a clinical picture which, except for a lesser extent of weight loss, is most closely concurrent with the clinical picture of ductal cancer in the head of the pancreas. Differentiation between these cancer forms in the periampular region is very difficult both pre- and postoperatively. Surgical treatment is, however, the same despite the origin of the tumor. The final diagnosis is obtained from the surgical specimen.
Metastasis from other tumors to the retroperitoneal space behind and in the head of the pancreas can sometimes be difficult to differentiate from tumors originating from the pancreas itself. For example, metastasis may develop from the kidneys, breast, colon, stomach, and melanoma. In certain cases, a radical resection may cure the disease or prolong recurrence, and in some cases, additional oncological treatment will extend lifetime and long-term absence of symptoms.
Lymphoma in the pancreas is rare.