Clinical response of dogs affected with transmissible venereal tumor (TVT) to the chemotherapeutic regime with regard to cytomorphology and histopathology

Canine transmissible venereal tumor (CTVT) is a contagious neoplasm that is physically transmitted through direct contact with injured skin or mucous. The aim of this study is to investigate the preferable rapid diagnosis and evaluative curing of CTVT with vincristine. Ten cases of transmissible venereal tumours eight bitches and two dogs which had been received for examination at the animal reproduction research institute, agriculture research centre during the time of January 2019 - December 2019. Nine animals showed genital vaginal and penile ulcerative neoplastic masses with bleeding, and one dog suffered from subcutaneous extragenital ulcerative metastatic lesions on the tail, backbone, and inguinal region. Under tranquilizer from the appeared tumor masses, we have taken aspirate and tissue biopsy for cytomorphology, histopathological and immunohistochemical evaluations. For treatment, animals were grouped into two groups according to the size of tumors G1 (size ≤ 100 cm3) and G2 (size > 100 cm3), each group was formed of four females and one male. Fasted animals for 12 hrs. were administrated weakly monotherapy of vincristine intravenously (i/v) with a dose of 0.025 mg/kg body weekly for 4 weeks (G1) and 6 weeks (G2) until total regression. Lymphocytic type recorded in nine genital vaginal and penile tumors, whereas the sole case of extragenital cutaneous revealed plasmacytic type. After 35 days of vincristine remedy, (G1) revealed (100%) total tumor regression while (G2) regressed after three to six weeks without relapse for 6 months. This study verified that; vincristine assessed in complete CTVT tumor regression without relapse within 6 months through its direct stopping outcomes on neoplastic cell proliferation. For treatment, animals were grouped into two groups according to the size of tumors G 1(size ≤ 100 cm3) and G 2 (size > 100 cm3), each group was formed of four females and one male. The animals were injected intravenously with 0.025 mg/kg body weight vincristine sulfate in saline weekly for a period of 4 weeks (G 1) and (G 2) for 6 weeks until a response was noted Cytological smears from animal groups were taken during and at the end of administration weekly. Results, Lymphocytic type was observed in nine genital vaginal and penile tumors, adding to one case of extragenital cutaneous plasmacytic TVT type. After 35 days in (G 1) and three to six weeks in (G 2) from medication, (100%) total tumor regression without relapse for 6 months was exhibited. Cytological smears of regressing tumor masses revealed a gradual decrease in tumor cells size as well as mitotic figures number. Conclusion: This study verified that; vincristine sulfate was assessed in complete tumor regression of (CTVT) in all dogs without relapse within 6 months through its direct stopping effects on tumor cell division Keywords: Genital, Vincristine sulfate. Canine, Transmissible venereal tumor, Cytomorphology, Histopathology