J Pathol Transl Med.  2022 May;56(3):170-171. 10.4132/jptm.2022.04.25.

What’s new in breast pathology 2022: WHO 5th edition and biomarker updates

• Muller K
• Jorns JM
• Tozbikian G

• KMID: 2529810
• DOI: http://doi.org/10.4132/jptm.2022.04.25

Abstract

The 5th edition WHO Classification of Breast Tumours (2019) has introduced changes to our practices. Highlights are presented below, with a focus on modifications to morphological subtype categorization. In addition, we summarize important updates to ER and PR testing made in the 2020 ASCO/CAP guidelines, and briefly discuss PD-L1 and Ki-67 testing in breast cancer.

Figure

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  Fig. 1. IBC-NST with medullary pattern. High-grade tumor with a syncytial growth pattern and prominent TILs.

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  Fig. 2. Phyllodes tumor with liposarcomatous differentiation. Other features (stromal atypia, mitotic activity) in this tumor supported the designation as malignant phyllodes tumor.

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  Fig. 3. Tall cell carcinoma with reverse polarity (TCCRP). The tumor is characterized by infiltration of nests of tumor cells with fibrovascular cores and bland columnar cells with apically-located nuclei and abundant eosinophilic cytoplasm.

Reference

References

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