RESUMO
AIMS: To evaluate the response to Sm153-EDTMP treatment in patients with metastatic bone pain and the existence of differences in the response according to the scintigraphic pattern (99mTc-MDP) and the primary tumor. MATERIAL AND METHODS: We have evaluated the response to Sm153-EDTMP treatment in 32 patients (17 male and 15 female) who received 38 doses (1 mCi/kg). The primary tumor was prostate cancer in 15 patients, breast in 13, lung in 2, intestinal carcinoid in one and unknown in one. Two types of response were considered: a) effective and b) non-effective. Patients were classified into 3 groups according to the metastatic pattern: 1) Superscan (SS), 2) Generalized metastases (GM) and 3) Regional metastases (RM). RESULTS: There was effective response in 24 doses (63.15%) and non-effective in 14 (36.84%). The mean duration of the response was 12.08 weeks. Patients with GM pattern showed 16 effective responses (76.19%) and 5 non-effective (23.8%). In SS pattern there were 6 effective responses (60%) and 4 non-effective (40%) and 2 effective (28.57%) and 5 non-effective (71.53%) in RM pattern. These differences did not reach statistical significance (p > 0.05). We did not find differences in the response between prostate cancer (12 effective and 6 non-effective) and breast cancer (10 effective and 6 non-effective) (p = 0.79968). CONCLUSIONS: Sm153-EDTMP treatment is efficacious in patients with metastatic bone pain with effective response in 63.15% of the treatments. The response percentage was lower in patients with RM pattern but the differences did not reach statistical significance. There were no differences in the response between prostate and breast cancer patients.