Incidence of skin tumors in dogs in Salvador, Bahia state, Brazil (2007-2016)

Abstract

This study aimed to establish the incidence of skin tumors (cutaneous proliferative lesions of neoplastic or non-neoplastic nature) in dogs diagnosed by histopathological evaluation at the Veterinary Pathology Laboratory (LPV) of the Federal University of Bahia (UFBA) in a 10-year (2007-2016) historical series. Of the 1945 histopathological diagnoses made in this period, 503 were skin biopsies, and 617 dermatological problems (87 dogs, 17.3%, presented more than one positive diagnosis) were found. Of the 617 diagnoses of dermatopathy, 546 (88.49%) were tumors and 71 (11.51%) were non-tumorous alterations. The 546 conditions more profoundly studied were from 453 dogs, 468 (85.7%) neoplastic and 78 (14.3%) non-neoplastic tumors. The 468 neoplasms were classified as follows: 230 benign (49.14%), 215 malignant (45.94%), 23 borderline (epitheliomas) (4.91%), 51.92% (243/468) mesenchymal, 42.74% (200/468) epithelial, 4.91% (23/468) melanocytic, and 0.43% (2/468) metastatic (mammary gland). The most commonly diagnosed neoplastic dermatopathies were mastocytoma (14.7%) and lipoma (7.48%). Among the 78 non-neoplastic conditions (14.3%), epidermal inclusion cyst (39.74%) and trichogranuloma (15.38%) were the most frequent. Canine dermatopathies accounted for 26% of the biopsy files of the LPV-UFBA. Distinct simultaneous dermatological problems were frequently found in the dogs assessed (one in six). Considering that these conditions can present with different cellular origin and biological behavior, it is crucial that histopathological evaluation be performed in fragments from the different cutaneous lesions.

Canine cutaneous neoplasms in the metropolitan region of Goiânia, Goiás state, Brazil

“…Skin tissue samples comprised of almost 50% of all canine samples during the period under evaluation. Previous studies have shown that skin lesions constitute the highest number of pathological diagnoses in dogs (Meirelles et al 2010, Silva et al 2011, Graf et al 2018, Machado et al 2018. Neoplastic lesions can range from 49.9% to 75.8% of all skin lesions (Souza et al 2006, Machado et al 2018), a finding similar to the results found in the present study.…”

“…About 9.8% of the dogs in this study had more than one skin neoplasms, irrespective of whether they were of the same histological type. Similar results were found in other studies, adding the chance of occurrence of non-neoplastic tumors (Souza et al 2006, Machado et al 2018. These data highlight the importance of the clinical veterinarians and the veterinary surgeons sending samples of all skin tumors for histological analysis, despite the possibility that they are of the same histological type.…”

“…In Brazil, regional studies were performed in several states such as Bahia (Machado et al 2018), Mato Grosso (Lima et al 2018), Ceará (Bastos et al 2017), Minas Gerais (Fernandes et al 2015), São Paulo (Scattone & Fava 2014), Paraíba (Andrade et al 2012), Rio de Janeiro (Silva et al 2011), Rio Grande do Sul (Souza et al 2006, Meirelles et al 2010, and Paraná (Nardi et al 2002). However, epidemiological data about canine skin neoplasms in the Goiás state are scarce.…”

Statistics of Canine Skin Tumors in Korea during 2005-2018

“…Recent studies have reviewed 11,740 canine skin tumors in Switzerland (Graf et al, 2018); 2,553 cases in South Africa (Tompkins et al, 2019); and 546 cases in Brazil (Machado et al, 2018). In these reports, tumors with most incidence were mast cell tumor and lipoma in common, and it was in accord with a previous report from Korea (Pakhrin et al, 2007).…”

“…Although there were some differences between the findings in this study and those of previous reports, tumors showing the highest frequency were generally similar between studies (Pakhrin et al, 2007;Graf et al, 2018;Machado et al, 2018). This may reflect that specific cell populations are particularly vulnerable to tumorigenic stimulation.…”