Vol. 9, Issue 10, Part J (2025)

Canine mast cell tumors are among the most common cutaneous neoplasms in dogs, with variable clinical behavior ranging from benign to highly aggressive forms. This study investigated the prevalence and pathomorphological features of mast cell tumors in 42 dogs diagnosed over a seven-month period. Tumor occurrence, clinical presentation, tumor location, cytological characteristics, and histopathological grading were analyzed. The age of occurrence of mast cell tumors ranged from 2 to 14 years, with the highest incidence in age group of 8 to 10 years and lowest incidence in age group of 12 to 14 years, with a mean age of 7.81 years, with a male predominance. Non-descript breeds were the most commonly affected, followed by Labrador and Golden Retrievers. The trunk was the most frequent tumor site. Cytological evaluation revealed characteristic round-to-oval mast cells with metachromatic granules and varying degrees of pleomorphism and anisokaryosis. Infiltration by eosinophils and neutrophils was frequently observed. Histopathological evaluation provided further characterization and grading of the tumors, using two widely accepted systems: Patnaik three-tier classification and the Kiupel two-tier system. Histopathology using Patnaik grading identified Grade II tumors as the most prevalent, while Kiupel grading showed an equal distribution of low-and high-grade tumors. These findings provide essential baseline data for improved diagnostic and therapeutic strategies in canine Mast cell tumors.