Brønden et al. Acta Veterinaria Scandinavica 2010, 52:6 http://www.actavetscand.com/content/52/1/6 Page 4 of 6 Table 3 Most commonly encountered neoplasms including the diagnostic method utilised and percentages of cases operated Diagnostic method Type of neoplasia Lipoma MCT Histiocytoma Adenoma, all STS Melanoma Total Histology Number/Pct surgery 18/89 65/53 46/98 42/98 27/89 19/95 354/91 Cytology Number/Pct surgery 164/23 49/91 52/44 51/33 8/38 2/50 411/36 Other Number/Pct surgery 6/33 2/100 2/100 2/100 - - 21/67 Total Number/Pct surgery 188/29 116/75 100/70 96/63 35/77 21/90 786/62 found in the current study. The most common benign neoplasms in the Norwegian study [1]were epithelial tumours (29.2% of all benign tumours reported), lipo- mas (17.4%) and histiocytomas (17.1%), figures being similar to the current study. In the Italian study mela- noma constituted only 4.1% of the skin malignancies [5], much lower than in the current study. The discrepancies among countries may be due to differences in dog populations, breed composition as well as cultural differ- ences in animal management as illustrated previously [1,11]. Mast cell tumours A recent review [9], Dobson and Scase discussed the diagnostic and therapeutic options of cutaneous MCT. Prognostic factors of significance included grading (cytology and histopathology), staging (regional and dis- tant metastases), breed, tumour localisation and treat- ment (surgery, radiation and chemotherapy). Cytological examination after fine needle aspiration is useful in establishing the diagnosis but histopathology is needed for grading [9]. Prognostic factors such as grade, metastases and tumour location are registered in the DVCR and the registry may be used for collection of cases for studies; both of cases that were treated following the recommen- dation for MCT treatment and cases that were not. The latter might provide an insight into the prognosis of ani- mals where owners rejected surgery or other treatment options. Suppl. corticosteroids 5 Euthanasia 2 Number: Total number of cases; Pct surgery: percentage of cases operated MCT: Mast cell tumours, STS: Soft tissue sarcoma Cytology was widely used for diagnosis of skin tumours (54%) and should be included in the registry data as this method is often the only diagnostic proce- dure performed. This was especially true for benign neoplasms. The proportion of neoplasms located in the skin was similar to data of a Norwegian study [1]. In an Ameri- can study including both benign and malignant neo- plasms, the proportion of tumours located in the skin was much lower (14.8%) [4]. If only malignant neo- plasms were considered, the proportion of the malignant skin neoplasms was 21% in the current study, again equal to figures of the Norwegian registry (21.7%) [1]. Comparative data from other countries were either lower or higher (9.5% (Italy) vs. 30.3% (USA)) [3,5]. The male to female ratio (M:F) in this study was 1.1 in regards to all neoplasms as well as malignant neoplasms alone. This gender distribution was similar to that found in the Norwegian as well as a Greek study (M:F 0.85 and 0.89, respectively) [1,10], but very different to an Italian study in which a majority of females was seen (M:F 2.58) [1,5]. In other veterinary studies the majority of the skin neoplasms were benign as in the current study [1,2,4,10]. In the Norwegian study [1], the most common malig- nant neoplasia types were MCT (45.4% of all malignan- cies reported), STS (19.7%) and epithelial tumours (15.4%) (Table 1). These figures correspond to those Table 4 Distribution of 114 cases of MCT Grade I Grade II Grade III Trunk incl. inguinal Perineal-genital Extremities Graded as Location Surgery 17 26 8 46 5 23 11 25 2 34 2 18