RESUMEN
Feline mammary carcinomas (FMC) are highly infiltrative tumours which show a strong tendency for local recurrence and metastasis. Histological type assessment of these tumours is not sufficiently discriminatory in predicting prognosis and in this study the prognostic significance of the Elston and Ellis method of histological grading was evaluated. Ninety-two feline mammary carcinomas from 84 cats were graded and 64 queens were included in a follow-up study. Grade was significantly related to tumour size (P=0.006), clinical stage (P=0.005), lymphovascular invasion (P<0.0001), mitotic index (P<0.0001), Ki67 index (P=0.001), overall survival (P=0.0001) and disease-free survival (P<0.0001). Cox regression analysis identified grade as an independent prognostic factor. Multivariable analysis also showed regional lymph node metastasis and lymphovascular emboli as independent prognostic factors related to overall survival and to disease-free-survival, respectively. The study demonstrated that histological grading can be used as a prognostic factor to evaluate the biological behaviour of FMC.
Asunto(s)
Enfermedades de los Gatos/mortalidad , Enfermedades de los Gatos/patología , Neoplasias Mamarias Animales/mortalidad , Neoplasias Mamarias Animales/patología , Animales , Gatos , Supervivencia sin Enfermedad , Femenino , Metástasis Linfática , Índice Mitótico , Análisis Multivariante , Estadificación de Neoplasias/veterinaria , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos ProporcionalesRESUMEN
Feline mammary carcinomas are known for their unfavourable prognosis due to a strong tendency to local recurrence and metastasis. We studied 73 spontaneous primary mammary carcinomas and identified eight cases presenting a biphasic nature, with neoplastic epithelial and myoepithelial cells (complex carcinoma). These cases presented histopathologic features associated with a better prognosis; they were also associated with higher overall survival and disease-free survival rates compared to other common invasive mammary carcinomas of non-specified type. Complex carcinoma appears to be a low-grade malignancy.