Canine Transmissible Venereal Tumor (TVT): Etiology, Epidemiology, Clinicopathology, and Therapeutic Management

Canine transmissible venereal tumor (TVT) is one of the oldest naturally occurring and unique contagious neoplasms affecting dogs, characterized by direct transmission of viable tumor cells, primarily during coitus. TVT is widely prevalent in tropical and subtropical regions and is the most commonly reported canine tumor in India. The disease predominantly affects sexually mature dogs, with higher incidence in bitches and seasonal variation linked to the estrus cycle. Clinically, TVT presents as friable, cauliflower-like genital masses accompanied by serosanguinous discharge, while extragenital involvement may occur in advanced or immunocompromised cases. Diagnosis is effectively achieved through exfoliative cytology and confirmed by histopathology, which reveals sheets of characteristic round cells with cytoplasmic vacuolation. Chemotherapy, especially vincristine sulfate, remains the treatment of choice, achieving high cure rates with minimal adverse effects, whereas surgery plays a limited adjunctive role.