Association between Ovarihysterectomy and Feline Mammary Carcinoma

Abstract

The etiopathogenesis of feline mammary carcinoma is not well understood. Although putative, risk factors include breed, reproductive status, and regular exposure to progestins. An association between age at ovarihysterectomy (OHE) and mammary carci-noma development has not been established. Therefore, a case-control study was performed to determine the effects of OHE age, breed, progestin exposure, and parity on feline mammary carcinoma development. Cases were female cats diagnosed with mammary carcinoma by histological examination of mammary tissue. Controls were female cats not diagnosed with mammary tumors selected from the same biopsy service population. Controls were frequency matched to cases by age and year of diagnosis. Questionnaires were sent to veterinarians for 308 cases and 400 controls. The overall questionnaire response rate was 58%. Intact cats were significantly overrepresented (odds ratio [OR] 2.7, confidence interval [CI] 1.4-5.3, P .001) in the mammary carcinoma population. Cats spayed prior to 6 months of age had a 91% reduction in the risk of mammary carcinoma development compared with intact cats (OR 0.9, CI 0.03-0.24). Those spayed prior to 1 year had an 86% reduction in risk (OR 0.14, CI 0.06-0.34). Parity did not affect feline mammary carcinoma development, and too few cats had progestin exposure to determine association with mammary carcinoma. Results indicate that cats spayed before 1 year of age are at significantly decreased risk of feline mammary carcinoma development.

Prognostic Value of Histologic Grading for Feline Mammary Carcinoma

“…26 Although feline mammary carcinomas tend to be biologically aggressive, survival times can vary significantly. 19,29,36 Prognosis in affected cats has been shown previously to be influenced by tumor diameter, 14,16,36,38,39 World Health Organization (WHO) stage and modified WHO stage, 14,34 extent of surgery, 16,25 and histologic grade.…”

Estudo retrospectivo de 207 casos de tumores mamários em gatas

“…Entretanto, no presente estudo não foi possível estabelecer qualquer ligação entre o efeito protetor da ovário-histerectomia (OH) nas gatas, devido à falta dessa informação na maioria dos protocolos. Sabe-se que, assim como ocorre em outras espécies, a taxa hormonal tem uma grande influência no desenvolvimento de tumores mamários em gatas e que, como em cadelas, a OH tem um papel importante na redução do risco de carcinoma mamário felino (Dorn et al 1968, Hayes & Mooney 1985, Overley et al 2005. A proteção conferida pela OH é de 91% quando o procedimento for realizado antes dos seis meses de idade, 86% quando realizado de sete a 12 meses e de apenas 11% quando o animal tem 13 a 24 meses.…”

“…A proteção conferida pela OH é de 91% quando o procedimento for realizado antes dos seis meses de idade, 86% quando realizado de sete a 12 meses e de apenas 11% quando o animal tem 13 a 24 meses. Não são observados benefícios na prevenção de carcinoma mamário felino quando a OH é executada após 24 meses de idade (Overley et al 2005).…”

Vor- und Nachteile der Kastration von Kätzinnen und Katern

“…Lebensjahr hat keinen präventiven Effekt auf die Entstehung maligner feliner Mammatumoren (Overley et al, 2005). Kater waren kastriert (Hawe, 1983;Carpenter et al, 1987;Hubbard et al, 1990;Caney et al, 1998;LeRoy und Lech, 2004).…”