Ambulatory radiosurgery in cerebral metastatic renal cell carcinoma. 5-year outcome in 58 patients

Brain metastases (BM) indicate an advanced stage of renal cell cancer (RCC). They pose an increasing challenge to urologists as a result of improved survival due to modern therapy. Median survival of untreated patients with BM who often suffer from neurological deficits is 3 months. Radiosurgery with the Gamma Knife (GK) has increased in use as an alternative to whole brain radiation therapy (WBRT) and/or surgery. This study reports the results of a consecutive series of RCC patients treated for BM by GK radiosurgery during a 5-year period. Between 1994 and 1999, 58 patients with a total of 277 BM and 3.0 (1-19) BM/patient were treated. Because of recurrent BM, 23 (40%) patients received repeated (multiple) GK sessions. The median tumor volume was 3.4 cm3 (0.1-19.1). The median interval between diagnosis of RCC and GK treatment was 2.2 years (0.1-17.2). Symptomatic side effects were detected in 9 (16%) of 58 patients. The median actuarial survival time was 9.9 months. Local tumor control could be achieved in 95% of patients. The GK therapy induced a significant tumor remission accompanied by rapid neurological improvement in 70% of patients. Compared to standard radiotherapy, GK radiosurgery is more effective, less time consuming, and can be repeated. Compared to surgery, radiosurgery is less invasive and better suited to treat multiple metastases in one single session. Surgery and radiosurgery, however, are supplementary methods that are highly effective to control intracerebral metastasizing RCC.