Teaching Case

We decribe a case of solitary pancreatic metastasis of renal cell carcinoma. The patient underwent CT and MR examinations; the imaging features suggested a diagnosis of pancreatic renal cell metastasis. Secondary pancreatic tumors should be considered in those patients who present with a solitary pancreatic mass and who have a history of previous extrapancreatic malignancy.

A 61-year-old male was admitted to our hospital for epigastric pain.Past history: Left nephrectomy 11 years ago for renal cell carcinoma. Physical examination revealead slight tenderness in the epigastrium. No evidence of hepato-slpenomegaly. Laboratory tests were normal. Presence of abundant gas within the stomach did not allow a complete and satisfactory US study of the upper abdomen. The patient underwent abdominal CT (both before and after contrast medium administration) and MR imaging of upper abdomen.

We report a case of solitary pancreatic metastasis of renal cell carcinoma in absence of local renal recurrence and other distant metasatses. The pancreas is an uncommon site for metastases from renal cell carcinoma (RCC). Metastases may occur many years after the initial diagnosis and treatment of the primary tumor. In most cases, pancreatic metastases occur as part of widespread nodal and visceral involvement [1], and there is thus evidence of metastatic disease in the body. The prevalence of metastatic involvement of the pancreas is not well known. Carcinoma of the breast, lung and thyroid gland are the most common primary neoplasms responsible for pancreatic metastases. The diagnosis of solitary pancreatic metastasis of RCC suggests surgical resection [2]; for this reason diagnostic imaging can play an important role in the management of these patients. The differential diagnosis of a pancreatic nodule includes pancreatic ductal adenocarcinoma and islet cell tumors. It must be noted that, in the early arterial-phase, pancreatic ductal adenocarcinoma is commonly hypovascular due to its desmoplastic reaction [3]; islet cell tumors generally show a hypervascular nature but have not a pseudocapsule [4]. Hypervascularity of the mass and detection of perilesional pseudocapsule [5] in the setting of history of renal cell carcinoma – that is a hypervascular tumor – suggested the diagnosis of metastatic disease to the pancreas. The patient underwent distal pancreatectomy and histological examination confirmed renal cell metastasis. Microscopic evaluation showed the presence of thick fibrous tissue (Fig 3) interposed between metastasis and pancreatic parenchyma. Secondary pancreatic tumors should be considered in those patients who present with a solitary pancreatic mass and who have a history of previous extrapancreatic malignancy.