The International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology: Introduction and Overview

  • Andrew S. FieldEmail author
  • Wendy A. Raymond
  • Mary T. Rickard
  • Lauren Arnold
  • Elena F. Brachtel
  • Benjaporn Chaiwun
  • Lan Chen
  • P. Y. Chong
  • Luigi Di Bonito
  • Rana S. Hoda
  • Daniel F. I. Kurtycz
  • Andrew H. S. Lee
  • Elgene Lim
  • Britt-Marie Ljung
  • Pamela Michelow
  • Robert Y. Osamura
  • Maurizio Pinamonti
  • Torill Sauer
  • Davendra Segara
  • Gary M. Tse
  • Philippe Vielh
  • Fernando Schmitt


The International Academy of Cytology (IAC) Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy (FNAB) Cytology reporting system is an initiative of the IAC that seeks to provide a comprehensive, standardized approach to breast FNAB reporting to facilitate reproducible cytopathology reporting and to establish best practice guidelines. The system is evidence-based, supports a structured reporting format and will aid in maximizing the usefulness of the FNAB technique and optimizing communication with the clinical team and the patient.

The use of five categories was chosen to maintain a high negative predictive value of a benign diagnosis and a high positive predictive value of a malignant diagnosis. The categories are Insufficient/Inadequate, Benign, Atypical, Suspicious of Malignancy and Malignant and stratify breast FNAB cytology by the risk of malignancy.

The role of FNAB and the technique of performing FNAB and making direct smears are presented.

The Atlas outlines the definitions for each of the categories and provides key cytological diagnostic criteria, differential diagnoses and photomicrographs for the range of specific diagnoses for each category. The Atlas addresses in detail the problem areas of atypical and suspicious of malignancy, in particular the interpretation of in situ and borderline lesions. A management chapter is included to assist in determining management for each category in a spectrum of clinical scenarios and with a range of medical resources.


Breast Fine needle aspiration biopsy Reporting system IAC Yokohama 


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Andrew S. Field
    • 1
    Email author
  • Wendy A. Raymond
    • 2
  • Mary T. Rickard
    • 3
  • Lauren Arnold
    • 4
  • Elena F. Brachtel
    • 5
  • Benjaporn Chaiwun
    • 6
  • Lan Chen
    • 7
  • P. Y. Chong
    • 8
  • Luigi Di Bonito
    • 9
  • Rana S. Hoda
    • 10
  • Daniel F. I. Kurtycz
    • 11
  • Andrew H. S. Lee
    • 12
  • Elgene Lim
    • 13
  • Britt-Marie Ljung
    • 14
  • Pamela Michelow
    • 15
  • Robert Y. Osamura
    • 16
  • Maurizio Pinamonti
    • 17
  • Torill Sauer
    • 18
  • Davendra Segara
    • 19
  • Gary M. Tse
    • 20
  • Philippe Vielh
    • 21
  • Fernando Schmitt
    • 22
  1. 1.University of NSW and University of Notre Dame Medical SchoolsSt Vincent’s HospitalSydneyAustralia
  2. 2.Flinders Medical Centre, Flinders University of South Australia and Clinpath LaboratoriesAdelaideAustralia
  3. 3.St. George Hospital, BreastScreenSydneyAustralia
  4. 4.Sydney Breast ClinicSydneyAustralia
  5. 5.Department of PathologyHarvard Medical School, Massachusetts General HospitalBostonUSA
  6. 6.Department of PathologyFaculty of Medicine, Chiangmai UniversityChiangmaiThailand
  7. 7.Department of PathologyBeijing Hospital and National Center of GerontologyBeijingChina
  8. 8.Department of PathologySengkang General HospitalSingaporeSingapore
  9. 9.Department of PathologyUniversity of TriesteTriesteItaly
  10. 10.CBLpath Laboratories, Department of CytopathologyRye BrookUSA
  11. 11.Department of Pathology and Laboratory Medicine University of Wisconsin, Madison, Medical Director, University of Wisconsin State Laboratory of Hygiene (WSLH), Director, Disease Prevention DivisionMadisonUSA
  12. 12.Department of HistopathologyNottingham University HospitalsNottinghamUK
  13. 13.St Vincent’s Hospital, Sydney, The Kinghorn Cancer CentreSydneyAustralia
  14. 14.Department of PathologyUniversity of California San FranciscoSan FranciscoUSA
  15. 15.Cytology Unit, Department of Anatomical PathologyFaculty of Health Science, University of the Witwatersrand and National Health Laboratory ServiceJohannesburgSouth Africa
  16. 16.Nippon Koukan Hospital, Keio University School of Medicine, Department of Diagnostic PathologyKawasakiJapan
  17. 17.Department of PathologyUniversity Hospital of TriesteTriesteItaly
  18. 18.Akershus University Hospital, Department of PathologyLørenskogNorway
  19. 19.St Vincent’s Private Hospital and St Vincent’s ClinicDepartment of SurgeryDarlinghurstAustralia
  20. 20.Prince of Wales Hospital, Department of Anatomical and Cellular PathologyKowloonHong Kong SAR
  21. 21.Medipath, American Hospital of Paris, Department of PathologyParisFrance
  22. 22.Institute of Molecular Pathology and Immunology of Porto University (IPATIMUP), Medical Faculty of Porto UniversityPortoPortugal

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