Veterinary researchers at the University of Cambridge are calling on UK vets to report suspected cases of canine transmissible venereal tumour (CTVT), following evidence that the unusual infectious cancer is once again being transmitted between dogs in the UK.
The Transmissible Cancer Group at Cambridge's Department of Veterinary Medicine is running a national pilot study, offering free PCR-based diagnostic testing to veterinary practices across the country.
CTVT is a rare form of cancer transmitted through the transfer of living tumour cells between dogs, usually during mating, although transmission can also occur through sniffing or licking affected areas. Once common in the UK, the disease was largely eliminated during the last century, but researchers say cases are increasing, partly due to the importation of dogs from countries where CTVT remains endemic.
A recent case report confirmed locally acquired CTVT in the UK for the first time in more than 50 years, raising concerns that the disease may be circulating within the domestic dog population.
CTVT typically causes friable, nodular masses affecting the external genitalia, often accompanied by haemorrhagic discharge. However, tumours can also develop at extragenital sites, including the nasal and oral cavities, following direct contact with affected lesions.
Researchers are concerned that UK vets may be unfamiliar with the disease because of its historically low prevalence. Although a history of importation or travel to an endemic region should raise suspicion, locally acquired cases mean that CTVT should not necessarily be ruled out in dogs without an overseas history.
Diagnosis traditionally relies on clinical history, cytology and histopathology. However, atypical presentations can be challenging to identify, particularly when CTVT is not initially suspected.
The Cambridge team is offering a PCR-based LINE-MYC assay to help confirm suspected cases, providing a more definitive diagnosis where conventional investigations are inconclusive.
CTVT is generally highly responsive to vincristine chemotherapy, making accurate identification particularly important.
The pilot study aims to improve understanding of CTVT transmission in the UK while developing more accessible diagnostic pathways for veterinary practices.
Researchers are encouraging clinicians to contact them about any suspected cases, including dogs with unusual lesions that could represent extragenital CTVT.
The team can accept samples in several formats for DNA extraction and aims to return results within a clinically useful timeframe. Veterinary practices are encouraged to contact the researchers before submitting samples to discuss the most appropriate material.
As well as supporting individual case management, samples submitted through the programme will help researchers investigate the extent to which CTVT is circulating in the UK.
Veterinary professionals can find more information about the pilot study and diagnostic testing on the Cambridge Transmissible Cancer Group website or contact Dr Andrea Strakova at as2112@cam.ac.uk.