Nonaspiration fine needle cytology and its histologic correlation in canine skin and soft tissue tumors

OBJECTIVE: To analyze the findings of nonaspiration fine needle (NAFN) cytology as compared with the histopathologic findings in evaluating canine skin and soft tissue tumors.STUDY DESIGN: NAFN (21-27 gauge) cytology was performed on 213 cases, Smears were air dried and stained by the Rosenfeld method (May-Grunwald-Giemsa modification). Histopathologic evaluation was available for comparison in 40% of cases.RESULTS: NAFN cytology and histopathology results were compared in 85 dogs. The size of the 117 lesions varied front 0.5 to 2 cm (n = 39), 2.1 to 5 cm (n = 43), and greater than or equal to5.2 (n = 35). There were 22 nonneoplastic lesions, mostly inflammatory processes and cysts. Neoplastic lesions were classified as epithelial (36%), mesenchymal (30%), round cell tumor (n = 13%) and melanocytic (2%). Among 40 malignant lesions, mast cell tumor (n = 14) and hemangiopericytoma (n = 9) were the most frequent, Lipoma (n = 14) and trichoblastoma (n = 10) were [lie most common benign neoplastic lesions. Cytology showed sensitivity of 89%, specificity of 100%, positive and negative predictive value of 100% and 96%, respectively, and efficacy of 97%.CONCLUSION: NAFN cytology is extremely useful and accurate. It is safe and avoids the use of anesthesia. Fia,ther, it is easy to perform and noninvasive and usually provides a high-quality sample.Univ Sao Paulo, Sch Vet, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Pathol, Sao Paulo, BrazilAdolfo Lutz Inst, Div Pathol, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Pathol, Sao Paulo, BrazilWeb of Scienc