Prognostic value of clinicopathological parameters and molecular subtypes in feline mammary carcinoma

Author(s)

Verônica Mollica Govoni

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2017-07-20

Examining board members

Bruno Cogliati; Maria Lucia Zaidan Dagli; Valter de Medeiros Winkel

• Advisor: Bruno Cogliati

Abstract

The mammary tumor is the third most frequent neoplasm in the feline species, followed by hematopoietic and cutaneous neoplasms. In cats, unlike that observed in dogs and humans, about 85 to 95% of mammary tumors are malignant and the disease tends to present more aggressive behavior. In this way, clinical-epidemiological, pathological and molecular parameters have been proposed as prognostic factors in this species, but the results are still controversial. Recently, a new molecular classification was proposed in this feline disease, in which six molecular subtypes were established according to \"St. Gallen International Expert Consensus Panel \"for humans. Thus, the present study had as main objective to investigate the prognostic value of clinical-pathological parameters and molecular subtypes in mammary carcinoma in felines. A total of 65 tumors were analyzed, from 42 cats treated in public and private veterinary hospitals. Tumors were submitted to histopathological and immunohistochemical analysis for the estrogen and progesterone receptors, HER-2, Ki67 and cytokeratin 5/6. The clinical-pathological parameters were correlated with survival by the log-rank test (p <0.05). The most frequent histological types were tubulopapillary carcinomas, solid and cribiform, commonly grade II. Tumors were classified as \"normal-like\" (35.4%), triple negative \"basal-like\" (29.1%), HER-2 positive (25%) and Luminais A And B (10.5%). Regarding the prognostic factors, animals aged over 12 years (p = 0.0036) and ulcerated tumors (p = 0.0139) showed a significant correlation with a shorter survival time. The parameters race, reproductive status, use of contraceptive, treatment, tumor size and volume, tumor multiplicity, morphology, histological grade, proliferation index and molecular subtypes had no correlation with survival. The results demonstrated here emphasize the importance of clinical, pathological and molecular correlation in the determination of prognostic factors and, consequently, in the development of new procedures and therapeutic targets. (AU)

• FAPESP's process: 15/15689-0 - Mutational evaluation of BRCA1 and BRCA2 genes in breast tumors in cats and correlation with clinical, histopathological and immunohistochemical aspects
• Grantee: Verônica Mollica Govoni
• Support Opportunities: Scholarships in Brazil - Master