Fine needle aspiration in domestic animals: a retrospective study.

Abstract

The aim of this work was to determine the efficacy of cytology for the diagnosis of malignancy and determination of its cellular origin in domestic animals. In this retrospective study, a comparison was made of fine needle aspiration and histological diagnoses of lesions from 498 animals. Cytological material was obtained by fine needle aspiration. Air-dried smears were stained by Giemsa or Wright stains. Tissues for histological examination were obtained by surgical biopsy or at necropsy, and were fixed in formalin and paraffin-embedded. Sections were stained routinely with haematoxylin and eosin. Other stains were eventually used. Diagnoses by the 2 methods were in agreement in 458 (92%) of the 498 cases. The lesions were classified as neoplasms of epithelial origin in 26,24% of the cases; 7,31% were neoplasms of mesenchymal origin and 37,64% were round cell tumors. Round cell tumors were classified as lymphomas, mast-cell tumors, histiocytomas, melanomas and transmissible venereal tumors (TVT). The results shows that fine needle aspiration have an accuracy of 92% and can supplement the clinician's diagnostic resources with a simple, quick and inexpensive technique.