Targeted radiotherapy with Sm-153-EDTMP in nine cases of canine primary bone tumours

Abstract

Nine dogs with primary bone tumours were treated with Samarium-153-EDTMP (Sm-153- EDTMP). Conventional treatment protocols were precluded by the size of the dogs and the owners' refusal of limb amputation. All the tumours were of the appendicular skeleton; 4 were confirmed osteosarcomas. The other 5 tumours were radiologically suspect for osteosarcoma. Bone scans were performed on all dogs using Technetium-99m-methylene diphosphonate (Tc-99m-MDP) before administration of Sm-153-EDTMP. Regions of interest were identified over the contralateral limb at the same site as the tumour and counts per pixel were recorded for the tumour and contralateral limb and expressed as a ratio. The dogs were given 1 injection of 37 MBq/kg (1 mCi/kg) of Sm-153-EDTMP intravenously. Thoracic and primary tumour site radiographs were taken at monthly or 2-monthly intervals to monitor progression of the primary tumour and search for evidence of metastasis. Two dogs showed no response to treatment, with an increase in bone pain, and were euthanased within 1 month. In 1 dog, a tumour of the scapula underwent complete involution and the dog is considered free of disease at 20 months post Sm-153-EDTMP treatment. The overall tumourcidal effect of a single dose of Sm-153-EDTMP on primary bone tumours was difficult to evaluate in this group of dogs, as, with one exception, all the primary tumours progressed over time and the dogs were euthanased. Pain control, for which Sm-155-EDTMP is used in man, was not evident, except in the dog that responded completely to treatment

Radiation therapy for canine appendicular osteosarcoma

“…Milner et al treated nine dogs with OSA (single intravenous dose of 37 MBq kg −1 153 Sm‐EDTMP). A single dog had a dramatic response to therapy, but all the others cases showed progression of the disease 58 . In 1999, Aas et al treated 15 dogs with 153 Sm‐EDTMP 59 .…”

Use of Force Plate Analysis to Evaluate the Efficacy of External Beam Radiation to Alleviate Osteosarcoma Pain

“…These dogs have concurrent orthopedic and/or neurologic disorders, are obese, or the owner declines amputation. Palliative care is recommended if amputation is not pursued 15–18 . One option for dogs unsuitable for amputation is palliative radiation therapy, which can result in decreased pain and improved limb function 19–21 .…”

Strategies for the targeted delivery of therapeutics for osteosarcoma

“…This agent was initially developed to treat painful bone metastasis, usually in the setting of palliation for diseases like prostate and breast cancer 63 . Brulan and colleagues proved the principal that this agent could be used for osteosarcoma using the companion canine model, an observation confirmed by other studies 64-66 . Subsequently, Pete Anderson and others have shown the utility of this agent in treating human osteosarcoma 67-69 .…”