The International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy (Cytopathology): An Institutional Study
Keywords:
Fine Needle Aspiration Biopsy; Breast Cancer; IAC Yokohama System; Risk of Malignancy; Diagnostic Accuracy; Histopathologic Correlation; Age Distribution.Abstract
Introduction: Fine Needle Aspiration Biopsy (FNAB) of the breast is a crucial diagnostic tool, especially for early detection of breast cancer. This minimally invasive procedure offers quick and accurate results, essential for timely clinical decision-making. To enhance the reliability and consistency of FNAB results, the International Academy of Cytology (IAC) Yokohama System was developed, providing a standardized reporting framework.
Objective: This study aims to evaluate the applicability and reliability of the IAC Yokohama System in categorizing breast FNAB samples and assessing the associated risk of malignancy (ROM).
Methods: A prospective observational study was conducted at G.S.V.M. Medical College, Kanpur, over two years (July 2022 to June 2024). FNAB samples from 214 female patients with breast masses were categorized using the Yokohama System. The study assessed the ROM for each category and evaluated the sensitivity, specificity, and predictive values (PV) for diagnosing malignancy. Statistical analysis included chi-square tests to determine the significance of observed distributions and associations.
Results: The majority of patients were in the 31-40 age group (24.30%). Of the 212 classified cases, 50% were malignant, 43.87% benign, 3.77% atypical, 1.42% suspicious for malignancy, and 0.94% insufficient material. The ROM was highest in the malignant category at 54.7%. Sensitivity, specificity, PPV, and NPV varied across three groups defined by different malignancy criteria, with the highest accuracy (75.26%) observed when only malignant cases were considered.
Conclusion: The IAC Yokohama System is effective in categorizing breast FNAB samples and aiding in malignancy diagnosis. It demonstrated significant diagnostic accuracy, particularly in the 31-40 age group. The system's structured approach enhances diagnostic confidence, especially in resource-limited settings. Further studies integrating emerging technologies are recommended to refine its clinical application.
