A Quantitative Study Of Myoepithelial Cells In Fine Needle Aspirate From Breast Lumps.

Abstract

BACKGROUND Fine needle aspiration cytology (FNAC) is a treasured tool in the evaluation of breast abnormalities. The main goal of breast FNA is to differentiate between benign or malignant lesions. Clinical and/or radiological findings are also correlated to avoid unnecessary surgery and to provide with a preoperative diagnosis of malignancy to allow proper patient counselling and definitive clinical management. The bimodal pattern of aggregates of cohesive epithelial cells myoepithelial cells and scattered single, bare, bipolar nuclei are diagnostic of benign tumor and non-neoplastic breast lesion. Studies in regard with the quantification and differentiation among different benign lesions on the basis of quantification of ME cells are quite few. This aspect therefore merits further investigations. OBJECTIVES OF THE STUDY To quantify the myoepithelial cells (ME cells) and to know the diagnostic utility of myoepithelial cells in aspirates of various breast lesions. MATERIALS AND METHODS All patients with breast lumps referred to the cytology section of the department of the Pathology Shri B.M. Patil Medical College, Hospital and Research Centre, BLDE (Deemed to be University) Vijayapura, for aspiration cytology were studied. A total of 124 cases were studied. A 22 or 23 gauge needle was used with 10 ml syringe for aspiration of material. Smears from aspirates were stained and mounted for microscopic evaluation. Quantitative estimation of ME cells per 1000 ductal cells with at least 20hpf (x40) were scanned and areas with the least overlapping of cells were selected. Number of ME cells was correlated with the cytological diagnosis. ME cells were counted as the cell with same or smaller size than that of epithelial cells with bipolar shape, dense, homogeneous chromatin, smooth nuclear outline without any nucleoli, with definable cytoplasm, distributed within the epithelial clusters. RESULTS DocuSign Envelope ID: 1D7425A31B79A627-B9C3EC71--446856BA--B9D2C708--374A6176B8D5B0DFA658379B XI 124 cases were included in the present study. The cases were between 04-84 years of age. The maximum number of cases were in 21-30 years age group (37.1%). The right breast was involved more than the left breast having 62 cases (50%) and 59 cases (47.6%) respectively, followed by 3 cases (2.4%) having bilateral involvement. Overall most common quadrant involved was superolateral (51 cases, 41.1%). Out of 124 cases, 100 cases (80.6%) were benign and 24 cases (19.4%) were malignant. The mean of ME cells in benign lesions was 342.3 ± 130.7, whereas the mean of ME cells in malignant lesions was 3.1 ± 5.7. The difference in the number of ME cells in benign and malignant lesions was significant (<0.001). Histopathology correlation was available for 30 cases (both benign and malignant), out of which 25 cases (83.3%) were concordant and 5 cases (16.7%) were discordant. CONCLUSION On quantification of ME cells, it was found that the mean of ME cells in benign lesions is greatly more when compared to malignant tumor and this difference was significant. Also it was found that there was a significant difference of mean of ME cells between benign non-neoplastic and benign neoplastic lesions. Hence, the quantification of ME cells helps to differentiate among various breast lesions