Background:Pain from skeletal metastases represents a complication of breast and prostate carcinoma. Bone-seeking radionuclides can target osteoblastic lesions to offer palliation but produce marrow toxicity. Thus radionuclide therapy, a needs to be administered according to a selection criterion. To set a logical criterion - bone lesion scoring system is devised, that is calculated by quantifying the pretherapy bone scan.
Aim:To device a quantitative method to predict the efficacy of radionuclide therapy for bone pain palliation.
Methods: 40 patients with carcinoma breast and prostate, with skeletal metastasis were enrolled. Bone lesion score was calculated on Tc MDP bone scan according to the bone lesion scoring system. Patients were injected 2600MBq of Lu-EDTMP after 1 week of bone scan and blood counts. Follow up of patients done every week to monitor pain response and hematology, monitored with the help of visual analogue scale ( 0-10). Bone lesion Score: Skull: 0=no 1= <2, 2= >2 Spine:0=no , 1= <2 , 2= 3-5 , 3= >5 Pelvis: 0=no , 1= < 10%, 2= 10-25%, 3= >25% Thorax: 0= no, 1= <2, 2= 3-5 , 3= >5 Extremities:0=no mets, 1= <2, 2= 3-5, 3= >5
Results: The followup of patients after 2600 MBq Lu-EDTMP showed a better pain palliative response with initial bone lesion score of below 8. With bone lesion score of 8-10, the pain score reduction can be graded as minimal. The pain palliation was negligible in cases with bone lesion score of 11-15.
Conclusions: Bone lesion score can be considered a predictor of success of radionuclide therapy. The patients with a score of more than 10 indicating extensive skeletal involvement should not be considered for radionuclide therapy as the risk of bone marrow suppression outweighs the palliative benefits.