The Placorhen Study: A Double-Blind, Placebo-Controlled, Randomized Radionuclide Study with 186Re-Etidronate in Hormone-Resistant Prostate Cancer Patients with Painful Bone Metastases

摘要

id="p-1">186Re-1,1-hydroxyethylidene diphosphonate (etidronate) can be used for the palliative treatment of metastatic bone pain. A randomized, placebo-controlled study using 186Re-etidronate was conducted on end-stage prostate cancer patients with metastatic bone pain. >Methods: Pain relief was assessed using an electronic diary containing questions reflecting the multidimensional character of chronic pain. The diary was marked twice daily for a maximum of 14 wk (2 wk before and 12 wk after the injection). Pain response was determined using a specific decision rule in which pain intensity, medication index, and daily activities were the core determinants. A positive response day was defined as a day on which pain intensity was reduced a‰￥25% compared with baseline values, while medication index and daily activities were at least constant, or on which pain intensity was reduced 25% and medication index or daily activities improved a‰￥25%, without worsening of the remaining factor. The total response (%) was defined as the number of positive response days divided by the number of days of follow-up. >Results: Of the 111 included patients, 79 were evaluable (43 186Re-etidronate, 36 placebo). Thirty-two patients were excluded from the analysis because of incomplete datasets. The total response of the patients treated with 186Re-etidronate varied from 0% to 96% (mean, 27%, or 23/84 d). In the placebo group, the total response varied from 0% to 80% (mean, 13%, or 11/84 d; Mann-Whitney U test, P 0.05). The number of patients who requested radiotherapy was higher in the placebo group (67%) than in the 186Re-etidronate group (44%) (relative risk, 1.51; Fishera€?s exact test, P = 0.069). >Conclusion: This randomized controlled trial confirmed that, compared with placebo, 186Re-etidronate resulted in a significantly longer pain response in the treatment of bone pain from metastasized prostate cancer.