[Giant renal cell carcinoma: a case report]

Though renal cell carcinoma is a fairly common disease, it is extremely rare to encounter a case providing a resected mass as large as over 2,000 g in weight. We report a case in which a giant 2,200 g tumor was resected after renal arterial embolization and interferon treatment for reduction of its size. A forty-three-year-old woman was first seen at a certain hospital with a chief complaint of fever and right flank pain. Under suspicion of right renal tumor, nephrectomy by extraperitoneal flank incision was attempted. However, the tumor was too large to be resected. After transfer to our department, she was treated by renal arterial embolization with absolute ethanol and steel coil and by the administration of interferon (rIFN-alpha A). As the tumor shrank to 77% of its original size on CT measurements and became mobile, transperitoneal nephrectomy was performed. The resected mass was as large as 12 x 12 x 21 cm. Pathologically, it was a clear cell type tumor showing mucinous degeneration and hyaline degeneration of tumor cells. Interferon used amounted to as high as 864 x 10(6) units, but no particular side effect occurred. No recurrence has been detected so far.