The incidence of renal cell carcinoma accounts for about 3% of all solid tumors. The incidence is increasing (1). The primary management of renal cell carcinoma is surgical. Most of the time metastases are already present at the time of diagnosis in more than half of the tumors. Once metastatic disease is present, the response rate of any treatment is low (15-20%) and the cure rate is only 6 to 8% (2-5). Factors which adversely influence prognosis are a high tumor stage, the histologic subtype, age, and co-morbidity factors. The histologic subtype of the tumor indeed plays an important role. It is well known that the conventional (clear cell) subtype is the only subtype that reacts to immunotherapy. The described spontaneous regression of metastases after nephrectomy or after an inflammatory syndrome, and the earlier successes with immunotherapy (and also due to the low success of chemotherapy) have resulted in an increased interest in the development of specific immunotherapy.
