- Canine Transmissible Venereal Tumor (CTVT)
- What is canine transmissible venereal tumor?
- What are the symptoms of CTVT?
- How is CTVT diagnosed, treated, and controlled?
WHAT IS CANINE TRANSMISSIBLE VENEREAL TUMOR?
What is CTVT?
CTVT is a cancer type found in male and female dogs, but studies indicate that it is more common in females since an infected male can mate with several females. However, the cancer is more likely to spread to other parts of the body in males than females, but the incidence of spread is still relatively low (0-17%).
The tumor develops because of the unregulated growth of immune cells called histiocytes. You can find the tumors primarily on the genitals, which allows for easy diagnosis of the disease, but lumps may also appear on the eyes, nose, mouth, anal area, and feet. Most often, CTVT spreads through mating, but it can also spread by licking, biting, and sniffing the tumor-affected area of an infected dog. Dogs of reproductive age, unneutered, and free-roaming are at the highest risk of contracting the disease, as well as dogs with a weakened immune system.
CTVT usually takes about 4 to 6 months to grow. Then it goes through a phase of stabilization, where there is little growth, followed by a spontaneous regression phase, where the tumor stops growing altogether, and the cancer cells disappear. However, not all tumors reach the final stage.
When the tumor grows, it usually begins as a single growing mass or nodule. The fusion of multiple nodules over time leads to a multi-nodular cauliflower-like appearance and discharge from the infected site. At the late stage, the tumors often ulcerate, become inflamed, and may bleed.
There are currently 3 classifications of canine venereal tumors, based on what the cells look like:
- Lymphocytic – when more than 60% of cells are round, have large central nuclei, and not many vacuoles (spaces) in the cytoplasm (clear, jelly-like substance in a cell), therefore looking like immune cells called lymphocytes
- Plasmacytic – when more than 60% of the cells have lots of cytoplasm, nuclei are situated to one side of the cell, and there are lots of vacuoles present
- Mixed type – a mixture of lymphocytic and plasmacytic cells
Although CTVT is common globally, there are steps you can take to prevent your dog from contracting this cancer. Several effective therapies, including chemotherapy, can successfully treat the tumor if your dog becomes infected, and you can take precautions to prevent the spread by isolating your infected dog until their illness resolves.
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Last Updated: July 29, 2022
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The following sources were referenced to write the content on this page:
Amaral, AS, Bassani-Silva, S, Ferreira, I, da Fonseca, LS, de Andrade, FHE, Gaspar, LFJ & Rocha, NS 2007, ‘Cytomorphological characterization of transmissible venereal tumor’, Revista Portuguesa de Ciencias Veterinarians, vol. 102, no. 563-564, pp.253-260.
Chikweto, A, Kumthekar, S, Larkin, H, Deallie, C, Tiwari, KP, Sharma, RN & Bhaiyat, MI 2013, ‘Genital and extragenital canine transmissible venereal tumor in dogs in Grenada, West Indies’, OJVM, vol. 3, no. 2, pp. 111-114.
Chowdary, SR, Raghunath, M, Sagar, PV, Sailaja, B, Kumar, PR & Krishna, NVVH 2016, ‘Cytomorphology of canine transmissible venereal tumours’, Int J Sci Environ Technol, vol. 5, no. 4, pp. 2239-2244.
Chu RM, Sun TJ, Yang HY, Wang DG, Liao WK, Chuang, TF & Lee, WC 2001, ‘Heat shock proteins in canine transmissible venereal tumor’, Vet Immunol Immunopathol, vol. 82, no. 1-2, pp. 9-21.
Das, U & Das, AK 2000, ‘Review of canine transmissible venereal sarcoma’, Vet Res Commun, vol. 24, no. 8, pp. 545-556.
Ferreira, AJA, Jaggy, A, Varejao, AP, Ferreira, MLP, Correia, JMJ, Mulas, JM, Almeida, O, Oliveira, P & Prada, J 2000, ‘Brain and ocular metastases from a transmissible venereal tumour in a dog’, JSAP, vol. 41, no. 4, pp. 165-168.
Ganguly, B, Das, U & Das, AK 2016, ‘Canine transmissible venereal tumour: a review’, Vet Comp Oncol, vol. 14, no. 1, pp. 1-12.
Kabuusu, RM, Stroup, DF & Fernandez, C 2010, ‘Risk factors and characteristics of canine transmissible venereal tumours in Grenada, West Indies’, Vet Comp Oncol, vol. 8, no. 1, pp. 50-55.
Liao, KW, Hung, SW, Hsiao, YW, Bennett, M & Chu, RM 2003, ‘Canine transmissible venereal tumor cell depletion of B lymphocytes: molecule(s) specifically toxic for B cells’, Vet Immunol Immunopathol, vol. 92, no. 3-4, pp.149-162.
Mac Ewen, EG 2001 Small Animal Clinical Oncology, 3 edn, Saunders, Philadelphia.
Mukaratirwa, S, Chimonyo, M, Obwolo, M, Gruys, E & Nederbragt, H, 2004, ‘Stromal cells and extracellular matrix components in spontaneous canine transmissible venereal tumour at different stages of growth’, Histol Histopathol, vol. 19, no. 4, pp. 1117-1123.
Murchison, EP, Wedge, DC, Alexandrov, LB, Fu, B, Martincorena, I, Ning, Z, Tubio, JMC, Werner, EI, Allen, J, De Nardi, AB, Donelan, EM, Marino, G, Fassati, A, Campbell, PJ, Yang, F, Burt, A, Weiss, RA & Stratton, MR 2014, ‘Transmissible dog cancer genome reveals the origin and history of an ancient cell lineage’, Science, vol. 343, no. 6169, pp. 437-440.
Nak, D, Nak, Y, Cangul, IT & Tuna, B 2005, ‘A Clinico-pathological study on the effect of vincristine on transmissible venereal tumour in dogs’, J Vet Med A Physiol Pathol Clin Med, vol. 52, no. 7, pp. 366-370.
Rogers, KS, Walker, MA & Dillon, HB 1998, ‘Transmissible venereal tumor: a retrospective study of 29 cases’, J Am Anim Hosp Assoc, vol. 34, no. 6, pp. 463-470.
Setthawongsin, C, Techangamsuwan, S & Rungsipipat, A 2022, Recent Advances in Canine Medicine, IntechOpen, London.
Setthawongsin, C, Tangkawattana, S, Rungsipipat, A & Techangamsuwan, S 2018, ‘Computerized cytomorphometric and cytomorphological analysis of canine transmissible venereal tumours’, J Comp Pathol, vol.163, pp. 18-22.
Setthawongsin, C, Teewasutrakul, P, Tangkawattana, S, Techangamsuwan, S & Rungsipipat, A 2019, ‘Conventional-vincristine sulfate vs. modified protocol of Vvncristine sulfate and L-asparaginase in canine transmissible venereal tumor’, Front Vet Sci, vol. 6, no. 300, pp. 1-12.
Singh, J, Rama, JS, Sood, N, Pangawkar, G & Gupta, PP 1996, ‘Clinico-pathological studies on the effect of different antineoplastic chemotherapy regimens on transmissible venereal tumours in dogs’, Vet Res Commun, vol. 20, no. 1, pp. 71–81.
Strakova, A & Murchison, EP 2014, ‘The changing global distribution and prevalence of canine transmissible venereal tumour’, BMC Vet Res, vol. 10, no. 168, pp. 1-10.
Villa, AA, Mvz, E, Dussán-Lubert, C & Pedraza-Ordoñez, F 2018, ‘Distribution and prevalence of transmissible venereal tumor in the Colombian canine population’,
Rev Colomb Cienc Pecu, vol. 31, no. 3, pp. 180-187.
Vural, SA, Haziroglu, R, Vural, MR, Polat, IM & Tunc, AS 2018, ‘Detection of progressive and regressive phase and LINE-1 retrotransposon in transfected dogs with transmissible venereal tumor during chemotherapy’, J Vet Sci, vol. 19, no. 5, pp. 620-626.
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