Correlation between fine-needle aspiration biopsy and routine histopathology in the diagnosis of spontaneous feline mammary gland tumours

Abstract

The present study evaluated the correlation between fine-needle aspiration biopsy and routine histopathological examination in the diagnosis of spontaneous mammary gland tumours in cats. From the studied 120 neoplastic growths, cytological diagnosis was correct in 111 cases (92.5%), and incorrect in 9 (7.5%) patients. Out of all studied tumours, 3 false positive (2.5%) and 6 false negative (5%) results were found out. Among benign tumours, cytological diagnosis was correct in 17 cases (94.44 %). Only one false negative diagnosis was demonstrated (5.56% of all benign tumours). As to malignant tumours, cytological diagnosis was correct in 94 (92.15%), and incorrect in 8 patients (7.85%). For diagnostics of feline mammary neoplasms, the sensitivity of cytology was 95.23%, the specificity - 75%, positive predictive value: 97.5% and negative predictive value: 60% compared to routine histopathology. The analysis with Cohen’s kappa test showed agreement of 99.17% (Cohen’s κ 0.96) between cytology and histopathology for benign and 94.17% (Cohen’s κ 0.75) for malignant mammary neoplasms.