Comparison of Cytological and Histomorphological Findings in Breast Tumours- A Study from a Tertiary Care Hospital in Southern India

Introduction: Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death in females. There is increasing awareness and the associated anxiety and stress among women, who perceive every symptom in breast as carcinoma, compels the patients to seek medical advice. Fine Needle Aspiration Cytology (FNAC) is a relatively simple, reliable, atraumatic, economical and complication free technique for the evaluation of mass lesions. Aim: To study the varied spectrum of breast tumours and to evaluate the diagnostic utility of cytological findings by comparing it with histopathological findings in breast tumours. Materials and Methods: The present study was a hospital- based cross-sectional study conducted in the Department of Pathology, Indira Gandhi Medical College and Research Institute, Pondicherry, India, from November 2017-October 2019. All cases of breast tumours, sent by surgeon, as out-patient or in- patient, who underwent FNAC followed by surgical biopsy, were included in this study. A total of 150 cases were studied. FNAC smears were stained using Haematoxylin and Eosin (H&E) and Papanicolaou (Pap) stains and air-dried smears were stained using May Grunwald Giemsa (MGG) stain. The excised specimen after surgery was subjected to detailed histopathological examination. Representative bits were taken from appropriate sites and stained using H&E stains, special stains and Immunohistochemistry (IHC) were carried out wherever necessary. Results: Majority of cases were in the age group of 21-30 years. There were 149 cases of female patients and only one case of male patient with breast carcinoma during the study period. Cytology showed 117 cases of benign tumours and 33 cases were malignant. Histopathology revealed 116 cases of benign tumours and 34 cases of malignant. One case was given as Atypical Ductal Hyperplasia (ADH) in cytology, found to be malignant Infiltrating Ductal Carcinoma (IDC) on histopathological examination. Five cases on cytology which were given as suspicious of carcinoma (C4 category) were found to be IDC on excision biopsy. Benign lesions were common in right breast, whereas malignant lesions were common in left breast. The diagnostic value of FNAC was assessed and showed sensitivity: 97.06%, specificity: 100%, Positive Predictive Value (PPV): 100%, Negative Predictive Value (NPV): 99.15% Accuracy of 99.33%. Conclusion: The present study was an attempt to compare cytological and histomorphological findings in breast tumours to know the diagnostic accuracy of FNAC and also studying the spectrum of breast lesions. The high specificity and negative predictive value showed high accuracy of FNAC in diagnosing the malignancy. It is an established method to determine the nature of breast lesions. In the present study, fibroadenoma was the commonest benign tumour and IDC- Not Otherwise Specified (NOS) type was the commonest malignant tumour.