Slow release cisplatin combined with radiation for the treatment of canine nasal tumors.
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 intramuscularly at a distant site, as a slow release delivery system (OPLA-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.
Lana
S E
SE
Department of Clinical Sciences, College of Veterinary Medicine and Biological Sciences, Colorado State University, St. Collins, USA.
Dernell
W S
WS
LaRue
S M
SM
Lafferty
M J
MJ
Douple
E B
EB
Brekke
J H
JH
Withrow
S J
SJ
D000818:Animals; D001706:Biopsy; D002945:Cisplatin / Q000008:administration & dosage* / Q000009:adverse effects; D003131:Combined Modality Therapy / Q000662:veterinary; D003692:Delayed-Action Preparations; D004283:Dog Diseases / Q000628:therapy*; D004285:Dogs; D005260:Female; D008297:Male; D015999:Multivariate Analysis; D009303:Nasopharyngeal Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy / Q000662:veterinary*; D015996:Survival Rate
D003692:Delayed-Action Preparations; D002945:Cisplatin