The Efficacy of Conventionally Fractionated Radiation in the Management of Osseous Metastases from Metastatic Renal Cell Carcinoma

BACKGROUND: There is little data regarding the effectiveness of palliative radiation with conventional fractionation for metastatic renal cell carcinoma (RCC), which has been described as radioresistant. We conducted a retrospective analysis of patients with metastatic bony disease from RCC treated with radiation therapy at our institution. METHODS: Forty patients with histologically confirmed RCC with a total of 53 treatment courses were included. Pain response after radiotherapy was recorded and freedom from progression was generated using posttreatment radiographs. Patient data was analyzed to assess influence on local control. RESULTS: Patients had a median age of 63. Median follow-up was 9.3 months. The most common radiation dose was 30 Gy in 10 fractions. Pain control after radiotherapy was achieved in 73.6% of patients. Increasing age was associated with nonresponse at the initial pain assessment post-RT (p = 0.02). In lesions with initial pain response, nonclear cell histology was associated with increased pain recurrence (p = 0.01) and a shorter duration to pain recurrence (p = 0.01). Radiographic control at 1 year was 62%. CONCLUSIONS: Pain response and control rates for osseous metastatic disease in RCC are comparable to other histologies when treated with conventional fractionation. These appear to be inferior to reported control rates from stereotactic treatments.