title: SAFETY AND TOXICITY OF AN ACCELERATED COARSELY FRACTIONATED RADIATION PROTOCOL FOR TREATMENT OF APPENDICULAR OSTEOSARCOMA IN 14 DOGS: 10 GY × 2 FRACTIONS.
abstract: Coarsely fractionated radiation is commonly used as a method for pain control in dogs with appendicular osteosarcoma, however there is little published information on optimal protocols. The aim of this retrospective, descriptive study was to report safety and toxicity findings in a sample of dogs with appendicular osteosarcoma that had been treated with a radiation scheme of 10 Gy delivered over two consecutive days for a total of 20 Gy. Dogs were included in the study if they had osteosarcoma that was treated with the aforementioned protocol. Dogs were excluded if treated with the same protocol for any other bone tumor besides osteosarcoma or inadequate follow-up. Thirteen of the 14 patients received adjuvant therapy with pamidronate and a nonsteroidal anti-inflammatory. Nine dogs received adjuvant chemotherapy with carboplatin after radiation was complete. Within a median of 14 days, 92.8% of dogs subjectively had improved pain control. Median duration of response (DOR) was 80 days (range 20-365). The majority of patients developed VRTOG grade one toxicity, primarily alopecia. Five dogs (35.7%) developed pathologic fracture postradiation treatment. Timing of fracture was variable ranging from 24 to 250 days. This radiation protocol was well tolerated, with minimal toxicity, subjectively improved survival time, and had the benefit of being completed in two consecutive days.
authors.affiliation: Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Dr., Baton Rouge, LA, 70803. cpagano@lsu.edu.
authors.forename: Candace
authors.initials: C
authors.lastname: Pagano
authors.affiliation: Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Dr., Baton Rouge, LA, 70803.
authors.forename: Bonnie
authors.initials: B
authors.lastname: Boudreaux
authors.affiliation: Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Dr., Baton Rouge, LA, 70803.
authors.forename: Keijiro
authors.initials: K
authors.lastname: Shiomitsu
mesh_terms: D000818:Animals; D050071:Bone Density Conservation Agents / Q000008:administration & dosage; D001859:Bone Neoplasms / Q000209:etiology / Q000532:radiotherapy / Q000662:veterinary*; D003131:Combined Modality Therapy / Q000009:adverse effects / Q000662:veterinary; D004164:Diphosphonates / Q000008:administration & dosage; D004283:Dog Diseases / Q000209:etiology / Q000532:radiotherapy*; D004285:Dogs; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005552:Forelimb; D006614:Hindlimb; D008297:Male; D012516:Osteosarcoma / Q000209:etiology / Q000532:radiotherapy / Q000821:virology*; D000077268:Pamidronate; D013902:Radiography, Thoracic / Q000662:veterinary*; D012189:Retrospective Studies
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D000077268:Pamidronate
keywords: appendicular; canine; coarsely fractionated; hypofractionated; osteosarcoma; pain relief; palliative; radiation