The use of bisphosphonate for the palliative treatment of painful bone metastasis due to hormone refractory prostate cancer

Purpose: Hormone refractory prostate cancer is dominated by osseous metasta ses leading to bone pain and pathological fractures. We assessed the clinic al efficacy of bisphosphonate in the management of symptomatic skeletal met astases due to prostate cancer. Materials and Methods: A total of 85 patients with painful osseous metastas es due to hormone refractory prostate cancer were treated with clodronate i n an open prospective nonrandomized clinical study. Clodronate was started as an intravenous phase for 8 days at a dose of 300 mg. daily followed by a n oral maintenance phase of 1,600 mg. daily. The primary study end point wa s decreased pain without an increase in analgesic medication for at least 2 consecutive measurements. Secondary end points were decreased analgesics, an improved Karnofsky index and mobility as well as the duration of bisphos phonate action. Decreased pain was documented by a 10-point visual analog s cale and consumption of analgesics was documented in a diary. Results: A palliative response with a significant decrease in mean pain sco re from 7.9 (range 6 to 10) to 2.5 (range 0 to 4) (p <0.001) was achieved i n 64 of the 85 patients (75%), 19 (22%) were completely pain-free without f urther need of analgesics and 45 significantly decreased the daily consumpt ion of analgesics. The mean duration of bisphosphonate action was 9 weeks ( range 4 to 22) and mean survival was 12 weeks (range 6 to 22). Improvement in bone pain was paralleled by an improvement in the mean Karnofsky index o f 45% (range 30% to 60%) to 70% (range 50% to 80%) at the end of the treatm ent period. Conclusions: Bisphosphonate treatment of painful osseous metastases due to hormone refractory prostate cancer results in a significant pain decrease a nd a significant decrease in the daily consumption of analgesics in 75% of patients. Each characteristic is paralleled by an increase in the Karnofsky index, mainly due to better mobility. Bisphosphonate should have a definit e role in the palliative management of symptomatic hormone refractory prost ate cancer.