Epidemiologic studies show increased frequency in tobacco users with highest risk in pipe and cigar smokers. There is also an increased incidence in patients on renal dialysis for many years. The vast majority of cases are sporadic but a few are inherited. These tend to be multifocal and bilateral and occur at a younger age than sporadic cases. Renal cell carcinoma usually causes no symptoms or dysfunction.
Hematuria is the single most common symptom and leads to secondary anemia.
About a third of patients present with distant metastases. The tumor may arise in any part of the kidney but commonly arises in the in the poles. They are large, spherical masses with well-delineated margins and a pseudocapsule of compressed, atrophic cortical tissue. The cut surface is yellow due to a large amount of intracytoplasmic lipid and there may be focal hemorrhages, necrosis or cyst formation in various combinations. Invasion of the renal capsule with extension into Gerota's fascia is common.