RT Journal Article SR Electronic T1 Phase 2 Study of a High Dose of 186Re-HEDP for Bone Pain Palliation in Patients with Widespread Skeletal Metastases JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP jnmt.113.124297 DO 10.2967/jnmt.113.124297 A1 Pirayesh, Elahe A1 Amoui, Mahasti A1 Mirzaee, Hamid Reza A1 Tabei, Faraj A1 Rakhsha, Afshin A1 Kalantari, Bagher Aziz A1 Shafiei, Babak A1 Assadi, Majid A1 Asli, Isa Neshandar YR 2013 UL http://tech.snmjournals.org/content/early/2013/08/02/jnmt.113.124297.abstract AB 186Re-1-hydroxyethylidene-1,1-diphosphonate (HEDP) is an attractive radiopharmaceutical for the treatment of bone pain arising from skeletal metastatic lesions. Currently, 186Re-HEDP is most commonly used in European countries. The aim of this study was to investigate the palliative efficacy and adverse effects of 186Re-HEDP in patients with different types of cancers and skeletal bone pain. Methods: Nineteen (8 male, 11 female) patients with various cancers (breast, prostate, renal cell carcinoma, colon, and neuroendocrine tumors) and painful bone metastases were included in the study. A dose of 1,480–3,330 MBq (40–90 mCi) of 186Re-HEDP was administered intravenously. The patients’ level of pain relief was assessed by the Visual Analog Scale for 8 wk after treatment and by a weekly blood cell count to evaluate for hematologic toxicity. Results: The overall response rate was 89.5%, and the mean pain score assessed by the Visual Analog Scale was reduced from 9.1 to 5.3 after 1 wk (P = 0.003). No adverse effects were reported by patients during intravenous administration or for up to 24 h after administration. A flare reaction was seen in 63.2% of patients, mainly during days 1–3, and lasted for 2–4 d. There was no significant correlation between the response to therapy and the flare reactions (P > 0.05). The nadir of platelet reduction occurred at the fourth or fifth week and led to platelet infusion in only 4 patients with a low baseline platelet count and diffuse skeletal metastases. Bone marrow suppression occurred in patients receiving higher doses, but no clinical problems were seen except in 2 patients who required packed cell transfusion similar to their prior transfusions. Conclusion: 186Re-HEDP is an effective radiopharmaceutical for the palliative treatment of metastatic bone pain and has minimal adverse effects.