Breast Fine needle Aspiration Biopsy Cytology Reporting using International Academy of Cytology Yokohama SystemTwo Year Retrospective Study in Tertiary Care Centre in Southern India

Abstract

Introduction: The study is based on application of recently proposed International Academy of cytology (IAC) Yokohama system of Breast cytology. Aim: The main objectives of the study were to categorise the Breast Fine Needle Aspiration Biopsy (FNAB) samples according to this new system of reporting and to assess the Risk of malignancy (ROM) for each category as well as the diagnostic yield of the Breast FNAB. Materials and Methods: A Total of 470 FNAB cytology specimens from January 2017 to December 2018 were obtained. These were studied and reclassified according to newly proposed IAC Yokohama system of reporting. The ROM was determined. The sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) and diagnostic yield of Breast FNAB were calculated accordingly. Results: The Breast FNAB samples were distributed as follows: insufficient material 5%, benign 71%, Atypical probably benign 1%, suspicious for malignancy 2% and malignant 21%. Of the 470 cases, 179 cases had histopathological correlation. The respective ROM for each category was 0% for category 1 (insufficient), 4% for category 2 (benign), 66% for category 3 (atypical), 83% for category 4 (suspicious for malignancy) and 99% for category 5 (Malignant). The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were respectively 94.59%, 98.9%, 98.59, 95.74% and 96.97%. Conclusion: Categorisation of the Breast FNAB cytology according to IAC Yokohama system of reporting helps pathologist in the diagnostic clarity and guides clinician in the appropriate patient management. IAC Yokohama system of reporting breast cytopathology serves as a common language to pathologist and clinician.

Keywords

• negative predictive value
• positive predictive value
• risk of malignancy