Canine transmissible venereal tumor

A canine transmissible venereal tumor (CTVT), also known as a transmissible venereal tumor (TVT), canine transmissible venereal sarcoma (CTVS), sticker tumor and infectious sarcoma, is a

The tumor cells are themselves the infectious agents, and the tumors that form are not genetically related to the host dog.

Canine TVTs were initially described by Russian veterinarian M.A. Novinsky (1841–1914) in 1876, when he demonstrated that the tumor could be transplanted from one dog to another by infecting them with tumor cells.^[7]

Signs and symptoms

In male

The success of this single cell lineage, believed to be the longest continually propagated cell lineage in the world, can be attributed to the tumor's mode of transmission in a specific host system. Although direct contact is generally not a highly efficient mode of transfer, CTVTs take advantage of the popular sire effect of domestic dogs. A single male can produce dozens of litters over his lifetime, allowing the tumor to affect many more females than it could if a monogamous species were the host. Understanding the epidemiology of CTVTs could provide insights for populations that may experience CTVT exposure and information about disease prevalence.^{[citation needed]}

Genetics

The CTVT cells have fewer

All tumor cells of this type of cancer share extremely similar genetic code, often if not always unrelated to the DNA of their host.^[6] In addition to the aforementioned c-myc insertion, a few other potential driver mutations have been identified.^[18]

Treatment method

The tumor, when treated with the chemotherapy drug vincristine, regresses as the host immune system is activated. CCL5 may play an important role in the immune response.^[19]

Treatment

Surgery may be difficult due to the location of these tumors. Surgery alone often leads to recurrence. Chemotherapy is very effective for TVTs. The prognosis for complete remission with chemotherapy is excellent.^[20] The most common chemotherapy agents used are vincristine, vinblastine, and doxorubicin.^[14] Radiotherapy may be required if chemotherapy does not work.^[17]

References