Retrospective evaluation of bone pain palliation after samarium-153-EDTMP therapy.
OBJECTIVE
The aim of this study was to evaluate the degree of metastatic bone pain palliation and medullar toxicity associated with samarium-153-EDTMP treatment.


METHODS
Seventy-three patients with metastatic bone pain having previously undergone therapy with samarium-153-EDTMP (1 mCi/kg) were retrospectively evaluated. Routine follow-up included pain evaluation and blood counts for 2 months after treatment. Pain was evaluated using a subjective scale (from 0 to 10) before and for 8 weeks after the treatment. Blood counts were obtained before treatment and once a week for 2 months during follow-up. Dosimetry, based upon the urinary excretion of the isotope, was estimated in 41 individuals, and the resulting radiation absorbed doses were correlated with hematological data.


RESULTS
Reduction in pain scores of 75% to 100% was obtained in 36 patients (49%), with a decrease of 50% to 75%, 25% to 50%, and 0% to 25% in, respectively, 20 (27%), 10 (14%), and 7 (10%) patients. There was no significant relationship between the pain response and location of the primary tumor (breast or prostate cancer). Mild to moderate myelosuppression was noted in 75.3% of patients, usually with hematological recovery at 8 weeks. The mean bone marrow dose was 347 +/- 65 cGy, and only a weak correlation was found between absorbed dose and myelosuppression (Pearson coefficient = .4).


CONCLUSIONS
Samarium-153-EDTMP is a valuable method for metastatic bone pain palliation. A mild to moderate and transitory myelosuppression is the main toxicity observed after samarium therapy, showing a weak correlation with dosimetric measures.
Sapienza
Marcelo Tatit
MT
Radiology Institute, Hospital das Clínicas, Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil. mtsapienza@hotmail.com
Ono
Carla Rachel
CR
Guimarães
Maria Inês Cury
MI
Watanabe
Tomoco
T
Costa
Paulo Aguirre
PA
Buchpiguel
Carlos Alberto
CA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage* / Q000009:adverse effects; D001853:Bone Marrow / Q000528:radiation effects*; D001859:Bone Neoplasms / Q000150:complications / Q000532:radiotherapy* / Q000556:secondary*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000009:adverse effects; D009943:Organophosphorus Compounds / Q000008:administration & dosage* / Q000009:adverse effects; D010146:Pain / Q000209:etiology* / Q000532:radiotherapy; D010147:Pain Measurement; D010166:Palliative Care / Q000379:methods*; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
D018712:Analgesics, Non-Narcotic; D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; C061972:samarium Sm-153 lexidronam