Suepaul, et al.; A review of neoplastic and non-neoplastic canine skin tumours in Trinidad from 2010-2015. Braz J Vet Pathol, 2019, 12(2), 41 – 47 DOI: 10.24070/bjvp.1983-0246.v12i2p41-47 Brazilian Journal of Veterinary Pathology. www.bjvp.org.br . All rights reserved 2007. 41 Original Full Paper A review of neoplastic and non-neoplastic canine skin tumours in Trinidad from 2010-2015 Rod Suepaul, Stacy Rajh, Karelma Frontera-Acevedo*, Indira Pargass, Sharianne Suepaul Department of Basic Veterinary Sciences, School of Veterinary Medicine, Faculty of Medical Sciences, School of Veterinary Medicine, University of West Indies, Champ Fleurs, Trinidad. *Corresponding author: E-mail: Karelma.fronteraacevedo@sta.uwi.edu Submitted November, 12 th 2018, Accepted March, 1 st 2019 Abstract This retrospective study was performed on samples submitted to the Pathology Unit of the School of Veterinary Medicine, Faculty of Medical Sciences, St. Augustine, Trinidad, during the period 2010 to 2015. A total of 471 non- inflammatory cutaneous masses were analyzed, of which 225 (47.8%) were malignant, 202 (42.9%) were benign and 44 (9.3%) were non-neoplastic. The most common malignant tumors were haemangiosarcoma, 50 (22.2%); mast cell tumour, 49 (21.8%); soft tissue sarcoma 35 (15.6%), lymphoma, 20 (8.9%) and melanoma 20 (8.9%). The most common benign tumors were haemangioma, 39 (19.3%); lipoma, 27 (13.4%), trichoblastoma, 26 (12.9%), histiocytoma 25 (12.4%), plasma cell tumor, 23 (11.4%) and papilloma 9 (4.5%). Common non-neoplastic skin lesions included collagen naevi, 26 (59.1%) and follicular cysts, 11 (25.0%). Mixed breed dogs 241 (51.2%), was most frequently represented with neoplasms followed by Rottweilers 50 (10.6%) and Pit bulls 48 (10.1%). Key words: canine, skin, neoplasia, comparative oncology, pathology, Trinidad. Introduction Canine neoplasia continues to be an important disease in dogs worldwide. In a UK study, it accounted for 27% of all deaths in purebred dogs (1). Dogs share our living environment and sometimes diet, which exposes them to similar risk factors as humans (2). Neoplasia is seen primarily in older dogs and with increased lifespans of dogs due to advances in veterinary medicine, one might expect an increase in neoplasia cases (3). In dogs, the skin has been one of the most common organs affected by neoplasia (4, 5). Skin neoplasia is readily detected by owners and easily accessed by veterinarians for diagnostic testing, a factor which is likely to contribute to the relatively high volume of skin biopsy submissions to diagnostic laboratories (6, 7). In Trinidad, the skin is the tissue most frequently sampled for biopsy, accounting for 69% (2010-2015) of the submissions to the histopathology laboratory at the School of Veterinary Medicine, The University of the West Indies (SVM). The prevalence of different types of skin neoplasia has been shown to vary in different regions; however, other factors such as breed prevalence in different geographical locations may affect the outcome of such studies (4, 7, 8). In one study in the UK, it was found that the most common tumor type was canine cutaneous histiocytoma, followed by lipoma, adenoma, soft tissue sarcoma, mast cell tumor, and lymphoma (8). A recent study on the neighbouring island of Grenada (4) found that the some of the most common skin neoplasms, were haemangiosarcoma, histiocytoma, melanocytoma and mast cell tumor. Geographical location may also influence the types of neoplasia that dogs develop, especially as it pertains to UV induced neoplasms. Grenada, like Trinidad, is a tropical island and the exposure to year round high levels of UV radiation could influence the types of neoplasms that develop in the skin, such as haemangiosarcoma, which are known to be induced by UV radiation and was the most commonly detected neoplasm in that study (4, 9). Exposure to UV radiation also