Histopathological findings in the early diagnosis of granulosa cell tumor in bitches.

Granulosa cell tumor (GCT) is a majorly observed ovarian tumor in female dogs. It is essential to diagnose GCT in its initial phase before any symptoms occur, as histological and physiological differences may be observed based on the evolution of this neoplasia. This study aimed to analyze the anatomic histopathology of GCT in its initial stage, with findings of ovaries not yet with the suspicion of neoplasms in the Canis familiaris. A sample including 55 ovaries that presented GCT in 40 female dogs. The histopathological analysis was performed considering the intensity of pleomorphism, vascularization, and inflammatory infiltrate. Furthermore, we evaluated the mitoses count in 10 fields using 40× magnification. Out of the 40 animals evaluated, 62.5% (25/40) presented the tumor in only one ovary. The Call-Exner corpuscle was present in 65% (26/40) of the cases. The follicular histological pattern was present in 52.5% (21/40) of the animals. The presence of the Call-Exner bodies and the degree of tumor cell pleomorphism (p = 0.033) were associated. Moreover, the degree of vascularization and the intensity of the inflammatory infiltrate were also related (p = 0.001). In addition, there was a positive relationship between the increase in pleomorphism and the mean age of the animals (p = 0.044). This study confirmed that the appearance of this tumor may precede any clinical symptomatology. In this study, the most frequent histopathological pattern was the follicular. The characteristics of the granulosa cell tumor diagnosed early were: poorly pleomorphic cells, low mitotic index and presence of Call-Exner body. This article is protected by copyright. All rights reserved.