Prognostic factors and survival of horses with ocular/adnexal squamous cell carcinoma: 147 cases (1978-1988)

J Am Vet Med Assoc. 1991 Jan 15;198(2):298-303.

Abstract

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)

MeSH terms

  • Animals
  • Carcinoma, Squamous Cell / diagnosis
  • Carcinoma, Squamous Cell / pathology
  • Carcinoma, Squamous Cell / veterinary*
  • Eye Neoplasms / diagnosis
  • Eye Neoplasms / pathology
  • Eye Neoplasms / veterinary*
  • Female
  • Follow-Up Studies
  • Horse Diseases / diagnosis
  • Horse Diseases / pathology*
  • Horses
  • Male
  • Neoplasm Recurrence, Local
  • Neoplasm Staging
  • Prognosis
  • Retrospective Studies