Bu olguda melez, erişkin, dişi bir köpeğin vajinasından alınan kitlede görülen fibrosarkoma histopatolojik ve immunohistokimyasal olarak incelenmiştir. Kitle, 10x5x3 cm boyutlarında, 75 g ağırlığında, multilobüler, yer yer kırmızımsısiyah, yer yer de boz beyaz renkte olup kesit yüzünde sirküler, ince çizgisel bantlar ve siyah kırmızı renkte nekrotik alanlar içeriyordu. Mikroskobik incelemede mukoza altında; kas dokuya kadar invaze olmuş, büyük çoğunluğu şişkin iğ şekilli, sosis benzeri, pleomorfik hücrelerden oluşan neoplazik değişiklik dikkati çekti. Tümör alanlarında çok sayıda dev hücreleri ve mitotik figürlere rastlandı. Yapılan immunohistokimyasal boyamalarda bu neoplazik hücrelerin sitoplazmalarının anti-vimentin antikoru ile yoğun boyandığı; antisitokeratin, anti-desmin ve anti-düz kas aktini antikorları ile boyanmadığı gözlendi. Proliferasyon belirteçleri (anti-PCNA, anti-Ki-67) yönünden yapılan immunohistokimyasal boyamalarda çok sayıda hücrede pozitiflik dikkati çekti. Kitleye fibrosarkoma tanısı konuldu. Sonuç olarak; köpekte vajinal fibrosarkoma nadir olarak görüldüğünden, olgunun patomorfolojik ve immunohistokimyasal bulgularının literatüre katkı sağlayacağı düşünülerek bilim camiası ile paylaşıldı. ●●● S U M M A R Y Vaginal Fibrosarcoma in a Dog In this case, the mass taken from the vagina of a cross breed, adult bitch was examined histopathologically and immunohistochemically. The mass is 10x5x3 cm in size, 75 g in weight and in the outlook the view of the mass is multilobular, reddish-black, gray and white colors from place to place. There were circular, thin linear bands on its cut-surface and also some areas contained reddish-black necrotic tissue. On the microscopic examination swollen spindleshaped, sausage-like, pleomorphic neoplastic cells were observed. These neoplastic cells invaded far into to muscle tissue. Giant cells and mitotic figures were observed in a large number of microscopic areas. In the immunohistochemical staining, cytoplasms of these neoplastic cells with antivimentin antibody are stained and with anti-cytokeratin, anti-desmin and antismooth muscle actin antibodies aren’t stained. In terms of proliferation markers (anti-PCNA, anti-Ki-67), immunohistochemically positive, a large number of positive cells were observed. The mass was diagnosed as a fibrosarcoma. In conclusion, due to the fact that vaginal fibrosarcoma are very rarely seen in dogs, we think that its pathomorphologic and immunohistochemical findings will contribute to the literature in this area.

Vaginal Fibrosarcoma in a Dog In this case, the mass taken from the vagina of a cross breed, adult bitch was examined histopathologically and immunohistochemically. The mass is 10x5x3 cm in size, 75 g in weight and in the outlook the view of the mass is multilobular, reddish-black, gray and white colors from place to place. There were circular, thin linear bands on its cut-surface and also some areas contained reddish-black necrotic tissue. On the microscopic examination swollen spindleshaped, sausage-like, pleomorphic neoplastic cells were observed. These neoplastic cells invaded far into to muscle tissue. Giant cells and mitotic figures were observed in a large number of microscopic areas. In the immunohistochemical staining, cytoplasms of these neoplastic cells with antivimentin antibody are stained and with anti-cytokeratin, anti-desmin and antismooth muscle actin antibodies aren’t stained. In terms of proliferation markers (anti-PCNA, anti-Ki-67), immunohistochemically positive, a large number of positive cells were observed. The mass was diagnosed as a fibrosarcoma. In conclusion, due to the fact that vaginal fibrosarcoma are very rarely seen in dogs, we think that its pathomorphologic and immunohistochemical findings will contribute to the literature in this area