Prognostic factors and survival of horses with ocular/adnexal squamous cell carcinoma: 147 cases (1978-1988).
Between January 1978 and December 1988, 147 horses with ocular/adnexal squamous cell carcinoma (SCC) were admitted to the Colorado State University Veterinary Teaching Hospital (CSU-VTH). Diagnosis was confirmed by histologic examination of appropriate tissue specimens. Medical records and communication with owners, referring veterinarians, or both provided information regarding initial examination, treatment at the CSU-VTH, and final outcome. At initial examination, 123 (83.7%) horses had unilateral involvement and 24 (16.3%) horses had bilateral involvement. The nictitating membrane, nasal canthus, or both (28.1%); limbus (27.5%); and eyelid (22.8%) were most commonly affected. In addition to the ocular/adnexal location, SCC was found elsewhere in 14 (9.5%) horses at initial examination. Adequate follow-up (greater than or equal to 4 months) for examination of tumor recurrence and survival analysis was obtained for 125 (85.0%) cases. After treatment at the CSU-VTH, tumor recurred in 30.4% of the cases. Tumor location, multiple vs single tumors at initial diagnosis, and CSU-VTH treatment modality influenced the recurrence of tumors. Survival analysis revealed a good prognosis for horses with ocular/adnexal SCC. Although undefined, a conservative estimate of the median survival time was 47 months. Six factors (treatment prior to referral, tumor location, tumor size, single or multiple tumors, treatment modality at the CSU-VTH, and recurrence or nonrecurrence) were analyzed to determine their relation with survival. Treatment prior to referral, multiple vs single tumors at initial examination, and treatment modality used at the CSU-VTH did not influence survival. Tumor location influenced survival; SCC involving the eyelid or orbit was associated with the poorest prognosis. Tumor stage (maximal dimension) was inversely related with survival.(ABSTRACT TRUNCATED AT 250 WORDS)
Dugan
S J
SJ
Department of Clinical Sciences, Veterinary Teaching Hospital, College of Veterinary Medicine and Biomedical Sciences, Colorado State University 80523.
Roberts
S M
SM
Curtis
C R
CR
Severin
G A
GA
D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D005134:Eye Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D005260:Female; D005500:Follow-Up Studies; D006734:Horse Diseases / Q000175:diagnosis / Q000473:pathology*; D006736:Horses; D008297:Male; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies