SLOW RELEASE CISPLATIN COMBINED WITH RADIATION FOR THE TREATMENT OF CANINE NASAL TUMORS

Publisher Website
Google Scholar
Abstract
Thirteen dogs with malignant tumors of the nasal cavity were treated with a combination of slow release cisplatin and megavoltage radiation. Radiation was delivered on a Monday through Friday schedule using a 6 MV linear accelerator. The median total dose was 49.5 Gy (range 49.5‐56 Gy). Cisplatin was given using an open‐cell polylactic acid polymer, impregnated with the drug and implanted intramus‐cularly at a distant site, as a slow release delivery system (OPLAn‐Pt [THM Biomedical, Inc]). The median dose used was 60 mg/m2 (range 60–100 mg/m2). When combined with radiation, this delivery system caused no systemic drug toxicity, and a local tissue reaction was seen in only two dogs. Acute side effects to normal tissue from radiation were not enhanced, as measured by subjective assessment. When compared to a group of historical controls that received radiation without OPLA‐Pt, the dogs that received combined radiation and cisplatin had longer overall survival times, with a median of 580 days. The control group had a median survival of 325 days. Previously reported median survival times for comparable megavoltage radiation treatment range from 6 to 13 months. Some dogs in both groups also received adjubant chemotherapy but this did not influence survival time. By multivariate analysis, only the use of OPLA‐Pt was found to significantly influence survival, with a p value of p = 0.023. Mega‐voltage radiation and slow release cisplatin appears to be a well tolerated combination that may favorably affect survival of dogs with nasal tumors.