Single-fraction radiosurgery for the treatment of renal tumors in singular renal units.

Abstract

e15168 Background: High-dose local radiation treatment (stereotactic radiosurgery, or SRS) was added for selected patients to improve local control and overall survival. We report on toxicity and local tumor control in patients with renal tumors who were treated with aggressive local irradiation using a single fraction SRS with the Cyberknife in singular renal units to avoid nephrectomy and consecutive hemodialysis. Methods: N=28 patients with renal tumors and an eastern cooperative oncology group (ECOG) status of 0 or 1 were treated with SRS. Patients with surgically removable renal lesions were not included. Prior to SRS gold markers were planted into the renal parenchyma under ultrasonographic guidance. Results: N=11 patients had transitional carcinoma of the renal pelvis and n=17 had renal cell carcinoma. No skin toxicity occurred after SRS, and SRS did not induce other side effects. Local tumor control 9 months after SRS was 98% (95% CI: 89-99%). There were no treatment related deaths, and late complications after SRS were not noted so far. Renal function remained stable with a median creatinine at baseline 1,5 mg/dl and 1,53 mg/dl after six months. None of the patients developed metastases during a median follow-up of 12 months. Dialysis and surgery were avoided in all patients. Conclusions: SRS for selected patients with renal tumors in singular renal units is safe and effective and maybe an alternative to surgery and consecutive hemodialysis. Single-fraction delivery as an outpatient procedure allows for convenient integration of SRS into various oncological treatment concepts. Further studies are needed to determine the limits of SRS in this setting.