Comparison of intratumoral administration of cisplatin versus bleomycin for treatment of periocular squamous cell carcinomas in horses.
OBJECTIVE
To compare therapeutic benefits of intratumoral administration of cisplatin and bleomycin for squamous cell carcinoma of the eyelids in horses.


METHODS
25 horses with 27 T2-stage periocular squamous cell carcinomas.


METHODS
Horses were treated 4 times at 2-week intervals with a slow-release formulation of cisplatin (1 mg/cm3 of tissue) or bleomycin (1 IU/cm3 of tissue). A two-stage design was used to minimize the sample size in each treatment arm.


RESULTS
The local control rate at 1 year for lesions treated with cisplatin was 93 +/- 6%, and with bleomycin was 78 +/- 10%. Difference in local control duration between the 2 treatment groups was not significantly different. A high tumor proliferative fraction index value was associated with a higher local (infield) control rate, but also with a higher risk of marginal and regional recurrences. Tumors with a low proliferative fraction index value (< 28%) had 9.5-times higher (P = 0.0411) risk of recurrence than those with a high index value. Local acute reactions were similar in the 2 treatment groups, and chronic reactions were not observed.


CONCLUSIONS
Cisplatin and bleomycin were effective anticancer agents for carcinoma of the eyelid in horses. Based on therapeutic benefit and treatment cost, cisplatin was found to be a better choice for intratumoral chemotherapy of eyelid carcinomas.


CONCLUSIONS
Results of this study confirm the value of intratumoral chemotherapy, using cisplatin, for treatment of cutaneous squamous cell carcinomas in horses.
Théon
A P
AP
Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis 95616-8745, USA.
Pascoe
J R
JR
Madigan
J E
JE
Carlson
G
G
Metzger
L
L
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage / Q000627:therapeutic use*; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001761:Bleomycin / Q000008:administration & dosage / Q000627:therapeutic use*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000662:veterinary*; D002945:Cisplatin / Q000008:administration & dosage / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D004305:Dose-Response Relationship, Drug; D005142:Eyelid Neoplasms / Q000188:drug therapy / Q000662:veterinary*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000627:therapeutic use; D006734:Horse Diseases / Q000188:drug therapy* / Q000517:prevention & control; D006736:Horses; D015552:Injections, Intralesional / Q000662:veterinary; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control / Q000662:veterinary; D013997:Time Factors
D000903:Antibiotics, Antineoplastic; D000964:Antimetabolites, Antineoplastic; D000970:Antineoplastic Agents; D003692:Delayed-Action Preparations; D001761:Bleomycin; D002945:Cisplatin; D005472:Fluorouracil