乳腺癌是全球女性最常见的癌症。细针穿刺活检（FNAB）可用作评估和早期诊断乳房病变的一线病理调查。FNAB有助于区分恶性病变和良性病变。在本研究中，我们根据国际细胞学学会Yokohama体系（IACYS）对乳腺FNAB细胞学进行分类，并评估每个类别的恶性风险（ROM）。乳房病变的回顾性数据来自2018年1月至2019年12月的病理学档案库。该研究获得了机构伦理委员会的批准。本研究仅包括123例具有细胞学和组织病理学相关性的病例。根据IACYS对报告乳腺FNAB细胞学，给予细胞学类别。FNAB结果包括不足材料3.25%（4/123）、良性46.34%（57/123）、非典型12.2%（15/123）、可疑恶性病变（SM）4.88%（6/123）和恶性33.33%（41/123）。对于NS、良性、非典型、SM和恶性，ROM分别为50%、7.27%、40.0%、83.33%和97.5%。FNAB是诊断和管理乳房病变的重要工具，特别是在资源有限的发展中国家（例如印度），其中核心针活检的实践受到限制。为了全球范围内细胞学报告的可重复性，5级IACYS对乳腺FNAB的报告有所改进，有助于分类乳房病变患者。©2021 Cytopathology Foundation Inc，Scientific Scholar出版。

Breast cancer is the most common cancer in women worldwide. The fine-needle aspiration biopsy (FNAB) may be used as the first-line pathological investigation for evaluation and early diagnosis of the breast lesion. The FNAB helps to differentiate malignant from benign lesions. In the present study, we categorized the breast FNAB cases according to the International Academy of Cytology Yokohama System (IACYS) for reporting breast FNAB cytology and to assess the risk of malignancy (ROM) for each category.A retrospective data of breast lesions were retrieved from the archives of pathology department between January 2018 and December 2019. The study got approval from the Institutional Ethics Committee. Only 123 cases with cytology and histopathological correlation were included in this study. The cytological category was given according to IACYS for reporting breast FNAB cytology.The FNAB results were include as insufficient material 3.25% (4/123), benign 46.34% (57/123), atypical 12.2% (15/123), suspicious for malignancy (SM) 4.88% (6/123), and malignant 33.33% (41/123). The ROM was 50%, 7.27%, 40.0%, 83.33%, and 97.5% for NS, benign, atypical, SM, and malignant, respectively.FNAB is an important tool in the diagnosis and management of breast lesions, especially in financial constrained developing countries like India with limited resources, where practice of core needle biopsy is limited. The 5-tier IACYS for reporting breast FNAB improves the reproducibility of cytology reports across the world and helps in triaging the breast lesion patients.© 2021 Cytopathology Foundation Inc, Published by Scientific Scholar.