Metastatic renal cell carcinoma to the pancreas.

A lthough the pancreas is not a common site of metastasis for renal cell carcinoma, it is the most common indication for pancreatectomy for metastatic disease. Metastatic disease may occur many years after nephrectomy (0.5-27 years in a recent article). Thompson and Heffess reviewed the combined English literature of 109 patients and reported that the interval between initial nephrectomy and presentation of metastasis averaged 8.4 years (range, 0.5-27 years). Renal cell carcinoma grows as a tissue chain, commonly into the renal vein and sometimes into the vena cava and right atrium. Approximately 16% of cases have intrarenal venous involvement, and 7% propagation into the vena cava. In our patient, intraoperatively, the tumor was palpated and the pancreas transected through grossly normal pancreatic parenchyma, but on transection, there was tissue filling the lumen of the main pancreatic duct proximally and distally. A frozen section was performed of the resection margin, which confirmed that the pancreatic parenchyma was free of disease, but free-floating tumor was present in the main pancreatic duct. Macroscopically, a 3 1 1–cm tumor occupied the body of the pancreas and was 1 cm to the left of the resection margin. The cut surface showed a well-defined, yellow tumor extending into the pancreatic duct. Histologic evaluation revealed that the epithelial lining of the duct showed no atypia or tumor involvement and that the intraductal tumor was free floating (Figure 2). Given that an adequate pancreatic parenchymal resection had been performed, attention was directed toward management of the remaining gross tumor in the proximal main pancreatic duct. Venotomy with balloon retrieval of renal cell cancer extending into the vena cava and atrium is well described, and in a similar fashion, we passed a No. 5 Fogarty balloon catheter through the main pancreatic duct into the duodenum and inflated the balloon. The Fogarty catheter was then removed, and a “cast” of the main pancreatic duct consisting of the free tumor extension from the renal cell metastasis was retrieved. We know of 3 cases of free extension of renal cell carcinomainto thepancreaticduct including1 into thecommon bileduct.Standardresectionisdescribed,withoutdescriptionofatechniquetoretrieveintraductalextensionoftumor. In patients with metastatic renal cell cancer, solitary metastases are frequently encountered, and evidence suggests that, in the case of metastasis to the pancreas, resection provides meaningful palliation and prolonged survival. Venous involvement in renal cell cancer carries a poorer prognosis, but removal of intravenous tumor burden improves long-term survival. It is unclear whether similar extrapolations can be made for extension along the pancreatic and bile ducts. Although extension of tumor into the pancreatic duct is rare, this growth pattern could be characteristic of metastatic tumors of renal cell origin. Surgical resection of isolated pancreatic metastases is advised, and its use may help themanagementoftumorextensionintothepancreaticduct.