Nuclear morphometry in 36 canine spontaneous perianal gland tumours.

Cytological samples from 36 spontaneous canine perianal gland tumours (18 adenomas and 18 adenocarcinomas) were examined. Neoplastic cells were preoperatively obtained by fine‑needle aspiration biopsy, fixed immediately with Merckofix spray® (Merck KGaA, Darmstadt, Germany) and stained with Hemacolor® (Merck KGaA, Darmstadt, Germany). Cytological smears were subjected to morphometric analysis by means of a digital microscope, PC station and image analysis software. The morphometric parameters evaluated in this study were mean nuclear area (MNA; μm2), mean nuclear perimeter (MNP; μm), mean nuclear diameter (D mean; μm), minimal nuclear diameter (D min; μm) and maximal nuclear diameter (D max). The results indicated an increase of the mean values of the nuclear parameters from canine perianal adenomas to canine perianal adenocarcinomas. The statistical analysis revealed significant differences between benign and malignant neoplastic cells (P < 0.01). The results in this study indicate that quantitative nuclear analysis could be used as an additional method for differentiating canine spontaneous perianal adenomas from carcinomas.