Grade is an independent prognostic factor for feline mammary carcinomas: a clinicopathological and survival analysis.
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.
Seixas
Fernanda
F
Centre of Animal and Veterinary Sciences, University of Trás-os-Montes e Alto Douro, 5000-811 Vila Real, Portugal. fseixas@utad.pt
Palmeira
Carlos
C
Pires
Maria Anjos
MA
Bento
Maria José
MJ
Lopes
Carlos
C
D000818:Animals; D002371:Cat Diseases / Q000401:mortality* / Q000473:pathology*; D002415:Cats; D018572:Disease-Free Survival; D005260:Female; D008207:Lymphatic Metastasis; D015674:Mammary Neoplasms, Animal / Q000401:mortality* / Q000473:pathology*; D008940:Mitotic Index; D015999:Multivariate Analysis; D009367:Neoplasm Staging / Q000662:veterinary; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models