Summary
Phyllodes tumours of the breast are uncommon fibroepithelial neoplasms that pose recurrent
classification challenges, in large part due to the multiple histological parameters
of stromal hypercellularity and atypia, stromal mitotic count, stromal overgrowth
and tumour borders, that are used for grading. While the World Health Organization
(WHO) Classification of Breast Tumours provides recommendations on diagnostic features,
defining criteria are not always applied in routine practice. Lack of concordance
among pathologists in typing and grading further underscores the classification difficulties,
especially in the borderline category. Although there has been significant molecular
information on phyllodes tumours in recent years which has been diagnostically helpful,
it has not been translated into daily clinical practice.
In order to refine the classification of phyllodes tumours into one that is simple
yet comprehensive, reproducible and prognostically precise, a multipronged approach
is needed that leverages on global contributions of the International Fibroepithelial
Consortium, support by the International Collaboration on Cancer Classification and
Research (IC3 R) in amalgamating evidence translation, and guidance from the International Collaboration
on Cancer Reporting (ICCR) for standardised reporting. It is hoped that the evidence
generated can be used towards refining the classification of phyllodes tumours for
the future.
Key words
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Article info
Publication history
Published online: April 19, 2023
Accepted:
February 5,
2023
Received in revised form:
January 17,
2023
Received:
November 20,
2022
Identification
Copyright
© 2023 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.
