The International Academy of Cytology Yokohama System in the Evaluation of Male Breast Lesions: Experience from a Rural Indian Center

Abstract Background: Male breast lesions are uncommon but pose significant diagnostic challenges, particularly in resource-limited rural settings. Distinguishing benign conditions like gynecomastia from malignancies is crucial for appropriate management. The present study employs the standardized International Academy of Cytology Yokohama framework to characterize male breast pathologies cytologically and evaluate fine-needle aspiration cytology (FNAC) diagnostic performance. Materials and Methods: A 1½ year study was done on male breast lesions presenting to a hospital in the Eastern part of India. A total of 50 cases were evaluated initially by FNAC which were followed with histology for further diagnostic evaluation (35 cases). Results: In FNAC, out of 50 cases, 39 cases were diagnosed as benign (78%). Gynecomastia was the most common presentation (76.9%) among the benign entities. Malignant features were seen in 7 cases (14%); 3 cases were suspicious of malignancy. Considering the ease of statistical analysis, cases were divided as benign and malignant which includes suspicious cases. Sensitivity of FNAC was found to be 100% and the negative predictive value was 100%. Conclusion: FNAC demonstrated 100% sensitivity and specificity in distinguishing benign from malignant lesions in this cohort, with a strong correlation to histopathological findings. Despite a limited sample size, this study supports FNAC as a first-line diagnostic tool in low-resource settings.