Brønden et al. Acta Veterinaria Scandinavica 2010, 52:6 http://www.actavetscand.com/content/52/1/6 Fine needle aspirations of MCT are usually rich in cells as these exfoliate easily and cytology is usually sufficient for a diagnosis of MCT. However for grading of the tumours, histopathology is necessary. Suggested prog- nostic factors in MCT include location, grade and stage. Prediction of outcome and treatment planning should be based on a panel of prognostic factors, rather than on a single prognostic factor since no such has proven superior to predict MCT prognosis alone [9,10]. Treat- ment of MCT may include surgery, radiation, che- motherapy or a combination hereof. Dobson and Scase [2] concluded in a recent review that grade I MCT require only local resection and grade II MCT may be successfully treated with a 2 cm margin and one fascial plane deep resection. Grade III MCT carries a poorer prognosis but treatment outcome may improve if adjunctive radiation or chemotherapy is administered. The objectives of the current study were, with a spe- cial focus on MCT to investigate the occurrence, gender distribution, biological behaviour, locations, types, the diagnostic method used and treatment of skin neo- plasms in dogs reported to the Danish Veterinary Can- cer Registry (DVCR). Furthermore the possible correlation between the diagnostic modality and the treatment elected will be investigated. Page 2 of 6 Materials and methods Canine cases entered in the DVCR from May 15th 2005 through February 29th 2008 were included in this study. They were selected based on location of a tumour in the skin, subcutaneous tissue or adnexa. The DVCR is a database of cases of neoplasia in Danish dogs and cats. It is an incident registry where each neoplasm is regarded as a separate entity, and data are collected pro- spectively. In contrast to other veterinary and human cancer registries DVCR comprises both benign and malignant neoplasms, and neoplasms diagnosed using other diagnostic methods than histology, such as cytol- ogy, diagnostic imaging etc. (Table 1). The base for the DVCR has been reported recently. Data were entered into an Excel spreadsheet and sta- tistical tests performed in SAS (version 9.1, SAS Insti- tute, Cary, NC, USA). Chi-square test was used to analyse proportions of cases having had surgery and his- topathology or cytology performed. P < 0.05 was consid- ered to be significant. Results A total of 1,768 cases of neoplasia in dogs were entered into the DVCR during the study period. 765 of these (43%, confidence interval (CI): 41.0-45.6) were located Table 1 Most common benign and malignant types of neoplasms in different studies. Registry Distribution benign/malignant Top 3 benign Pct of all skin tumours (Pct of all benign tumours) Top 3 malignant Pct of total skin (pct of all malignant skin tumours) Registry Distribution benign/malignant Top 3 benign Pct of all skin tumours (Pct of all benign tumours) Top 3 malignant Pct of total skin (pct of all malignant skin tumours) Australia Australia Greece Korea [15] [16] [10] [17] #, N = 1000 #, N = 1000 #, N = 174 #, N = 748 B: 41.9% B: 48.2% B: 53.4% B: 69% M: 58.1% M: 52.8% M: 46.6% M: 31% Basal cell tumour Histiocytoma 14.0% (29.0%) Hepato gl. adenoma 9.8% Epidermal cysts 12.7% 12.0% (20.7%) Lipoma 6.0% (12.4%) (18.3%) (18.3%) Perianal gl. adenomas Basal cell epithelioma 5.5% Lipoma 5.7% (10.8%) Lipoma 11.4% (16.4%) 8.3% (19.8%) (11.4%) Histiocytoma 5.7% (10.8%) Histiocytoma 7.5% Histiocytoma 7.8% (10.8%) (18.6%) MCT 17.6% (30.3%) MCT 16.1% (31.1%) MCT 13.8% (29.6%) MCT 8.8% (28.7%) STS 8.5% (14.6%) STS 14.4% (27.8%) STS 10.3% (22.2%) STS 3.3% (10.9%) Melanoma 6.8% SCC 6.9% (13.3%) Basal cell carcinoma 4.0% (8.6%) Apocrine (11.7%) adenocarcinoma 3.1% (10.0%) Norway South Africa USA [1] [18] [3] #, N = 7401 #; N = 903 #, N = 277 M: 22% B: 54.4% M: 100% M: 45.6% Epidermal adenoma 22.7% Basal cell tumour 18.8% (34.6%) - (29.2%) Perineal gland adenoma 13.4% Lipoma 13.6% (17.4%) (24.6%) Histiocytoma 13.3% (17.1%) Sebaceous gland adenomas and cysts 6.1% (11.2%) MCT 10.0 (45.4%) SCC 16.4% (35.9%) MCT (27%) STS 4.3% (19.6%) Melanoma 11.4% (25.0%) Adenocarcinoma (26%) Malignant epidermal MCT 8.9% (19.4%) Melanoma (22%) tumours 3.4% (15.4%) MCT: Mast cell tumours, SCC: Squamous cell carcinoma, STS: Soft tissue sarcoma