Objective: The aim of this study was to assess the utility of the morphometric parameters in cytological aspirates in the categorization of breast lesions.

Material and Method: The study was carried out on 50 females presenting with a breast lump for fine needle aspiration cytology. Air-dried smears from the aspirate were stained with Leishman and Giemsa stains while alcohol-fixed preparations were stained with the PAP stain. They were subsequently categorized into benign, borderline and malignant categories on light microscopy. Morphometry was performed on the stained smears. The morphometric parameters studied were mean nuclear area, mean cytoplasmic area, perimeter and nuclear/cytoplasm ratio.

Results: Morphometric parameters revealed a progressive and statistically significant increase in values from benign to borderline to malignant cases. On comparing benign with borderline and malignant, all the four parameters were found to be statistically significant with a p-value of less than 0.05 while on comparing borderline with malignant, two of the parameters, i.e. mean nuclear area and mean cytoplasmic area, were statistically significant.

Conclusion: This study introduces morphometry as a highly objective tool to supplement the entirely subjective fine needle aspiration cytology in the crucial differentiation of benign from malignant lesions and especially the borderline cases in the gray zone comprising of atypical ductal hyperplasia and ductal carcinoma in situ.