[Effect of radiotherapy and bisphosphonate on bone metastases from renal cell carcinoma]

Bone metastases from renal cell carcinoma(RCC)are almost osteolytic and often cause pathological fractures. The objective of this study was to assess the efficacy of radiotherapy and zoledronic acid in patients with bone metastases from RCC.

We retrospectively analyzed 12 patients with bone metastases from RCC. Of these patients, 5 were treated with radiotherapy(RT group)and 7 were treated with a combination of radiotherapy and zoledronic acid(RT+Z group). We analyzed the radiological changes in the bone metastases and evaluated the response rate, survival rate, and skeletal-related event(SRE)rate.

Radiologically, 2 patients showed progressive disease(PD), 3 showed stable disease( SD), 1 showed partial response(PR), and 1 showed complete response(CR)in the RT group(response rate: 28.6%). In the RT+Z group, 1 patient showed PD, 3 showed PR, and 1 showed CR(response rate: 80.0%).

With regard to radiological changes, the response rate was higher in the RT group than in the RT+Z group, but the survival rate did not differ significantly between the 2 groups. SREs were less frequent in the RT+Z group than in the RT group.