A canine transmissible venereal tumor (CTVT), also known as transmissible venereal tumor (TVT) or Sticker’s sarcoma, is contagious cancer that affects dogs when they come into contact. The cancer cells physically ‘transplant’ themselves from one animal to the other. CTVT commonly affects dogs’ genitals and is usually transmitted during mating. But sometimes, cancer can affect other areas like the nose, mouth, and skin.
Given that sniffing and licking transmission behaviors may differ between sexes, a study by the University of Cambridge‘s Department of Veterinary Medicine determined whether oronasal CTVT shows sex disparity. They found that male dogs are four to five times more likely than female dogs to be infected with this cancer. This is likely to happen because male dogs spend more time sniffing and licking female dogs’ genitalia than vice versa.
In the study, scientists reviewed a database of almost 2,000 cases of CTVT from around the globe and found that only 32 CTVT tumors affected the nose or mouth. Of these, 27 cases were in male dogs.
Dr. Andrea Strakova in the University of Cambridge’s Department of Veterinary Medicine, the first author of the paper, said, “We found that a very significant proportion of the nose or mouth tumors of canine transmissible cancer were in male dogs.”
“We think this is because male dogs may prefer sniffing or licking the female genitalia, compared to vice versa. The female genital tumors may also be more accessible for sniffing and licking, compared to the male genital tumors.”
“Although canine transmissible cancer can be diagnosed and treated fairly easily, veterinarians in the UK may not be familiar with the signs of the disease because it is very rare here.”
“We think it’s important to consider CTVT as a possible diagnosis for oro-nasal tumors in dogs. Treatment is very effective, using single-agent Vincristine chemotherapy, and most dogs recover.”
The research was funded by the Wellcome and International Canine Health Postgraduate Student Inspiration Awards from the Kennel Club Charitable Trust.
- Strakova, A. et al.: ‘Sex disparity in oronasal presentations of canine transmissible venereal tumour.’ Veterinary Record, July 2022. DOI: 10.1002/vetr.1794