Transmisibil Venereal Tümör: Derleme

Öz

Transmisibil Venereal Tümör (TVT), erkek ve dişi köpeklerin çiftleşme sırasında canlı tümör hücrelerinin fiziksel transferi ile bulaşabilen neoplastik bir yapıdır. Tümör etkilenen lezyonların koklanması, yalanması, tırmalanması ve ısırılmasıyla vücudun farklı bölgelerine yayılabilir. TVT aynı zamanda vahşi kornivorlarda da gözlenebilir. Tümör genellikle erkek köpeklerde penisin kaudal kısmında lokalize olurken, dişilerde çoğunlukla vajinanın posteriyör bölgesinde, vestibulum ve vajinanın birleşme yerinde şekillenir. İlk başlarda tümör küçük ve pembeden kırmızı renge değişen şekildedir, daha sonra büyük ülserasyonlu ve kontamine bir kitle haline dönüşür. İlerleyen zamanlarda tümörün hacmi artar ve şekillenen lezyonlar multilobüler, karnıbahar görünümünde olup gevrek, hiperemik ve hemorajik yapıdadırlar. Serösangionöz vajinal akıntı gözlenir. Tümörün kesin tanısı anemnez bilgilerine, kitlenin oluşum yerine, sitolojik ve histolojik bulgulara dayanmaktadır. Preparatlardaki hücreler yuvarlak, oval veya değişik yüzeyli yapıda olup, solgun mavi veya renksiz sitoplazma ile belirgin bir nükleus içerirler. Hücrelerde küçük, parlak ve temiz görünümlü intrastoplazmik vakuoller bulunur. TVT’nin oluşumunu tamamen engelleyecek bir yöntem olmadığı için, teşhis edildiğinde derhal tedavi edilmesi gerekir. Kemoterapi TVT için etkili bir sağaltım yöntemidir. Kemoteröpatik ajan olan vinkristin sülfatın haftada bir kez, ortalama 3 hafta süreyle damar içi yolla verilmesi sonrasında iyi sonuçlar alınmaktadır. Tedavi oranı %90-95 arasındadır. Sunulan bu derlemede, TVT’nin insidansı, patogenezi, klinik bulguları, tanısı, prognozu ve tedavisi üzerinde durulmuştur.

Anahtar Kelimeler

• Diagnoz,Etiyopatogenez,Incidens,Prognoz,Tedavi,Transmisibil Venereal Tümor

Transmissible Venereal Tumor: A Review

Öz

Transmissible venereal tumor (TVT) is a neoplasm that can be transmitted between female and male dogs via mating by the physical transfer of viable tumor cells. The tumor may spread to different parts of the body through sniffing, licking, scratching or biting affected lesions. It can be also observed in wild carnivores. TVT is mostly located in the posterior wall of the vagina, in the joint of vaginal vestibule and vagina in female dogs, while it is usually located in caudal part of the penis in males. Initially, the tumor is small and varying from pink to red, subsequently progressing to a large, ulcerated, and contaminated mass. By the time, the tumor’s volume increases and the lesions become friable, hyperemic, hemorrhagic, multilobular and cauliflower-like masses. A serosanguinous vaginal discharge is observed. Definitive diagnosis is based on anamnesis, location of the mass, cytological and histological findings. The cells in the slides vary from round to oval or variable shapes and contain a pale blue or colorless cytoplasm with a single distinctive nucleus. They include small, light, clear intracytoplasmic vacuoles. TVT should be immediately treated as soon as diagnosed because there is no method to prevent it. Chemotherapy is the effective method for the treatment of TVT with the intravenous use of vincristine sulfate, which is a chemotherapeutic agent, once in a week for approximately three weeks applications. The cure rate varies at 90-95%. In this review, the incidence, etiopathogenesis, clinical findings, diagnosis, prognosis and therapies of TVT have been emphasized.

Anahtar Kelimeler

• Diagnosis,Etiopathogenesis,Incidence,Prognosis,Transmissible Venereal Tumor,Treatment

Kaynakça

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