WHO Classification of Tumours 5th Edition: Evolving Issues in Classification, Diagnosis and Prognostication of Prostate Cancer.

The 5th edition of the WHO Classification of Tumours of the Urinary and Male Genital Systems encompasses several updates to the classification and diagnosis of prostatic carcinoma as well as incorporating advancements in assessment of its prognosis, including recent grading modifications. Some of the salient aspects include: 1) recognition that PIN-like carcinoma is not synonymous with a pattern of ductal carcinoma but better classified as a subtype of acinar adenocarcinoma; 2) a specific section on treatment-related neuroendocrine prostatic carcinoma in view of the tight correlation between androgen deprivation therapy and the development of prostatic carcinoma with neuroendocrine morphology, and the emerging data on lineage plasticity; 3) a terminology change of basal cell carcinoma to "adenoid cystic (basal cell) cell carcinoma" given the presence of an underlying MYB::NFIB gene fusion in many cases; 4) discussion of the current issues in the grading of acinar adenocarcinoma and the prognostic significance of cribriform growth patterns; and 5) more detailed coverage of intraductal carcinoma of prostate (IDC-P) reflecting our increased knowledge of this entity, while recommending the descriptive term atypical intraductal proliferation (AIP) for lesions falling short of IDC-P but containing more atypia than typically seen in high-grade prostatic intraepithelial neoplasia (HGPIN). Lesions previously regarded as cribriform patterns of HGPIN are now included in the AIP category. This review discusses these developments, summarising the existing literature, as well as the emerging morphological and molecular data that underpins the classification and prognostication of prostatic carcinoma.

Histopathology. 2022 Jun 27 [Epub ahead of print]

James G Kench, Mahul B Amin, Daniel M Berney, Eva M Compérat, Ian A Cree, Anthony J Gill, Arndt Hartmann, Santosh Menon, Holger Moch, George J Netto, Maria R Raspollini, Mark A Rubin, Puay Hoon Tan, Toyonori Tsuzuki, Samra Turjalic, Theo H van der Kwast, Ming Zhou, John R Srigley

Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, NSW Health Pathology, Camperdown, NSW, Australia., The University of Tennessee Health Science Center, Memphis, Tennessee, USA., Department of Cellular Pathology, Bartshealth NHS Trust, Royal London Hospital, London, UK., Department of Pathology, University of Vienna, Vienna, Austria., International Agency for Research on Cancer, Lyon, France., The University of Sydney, Camperdown, NSW, Australia., Institute of Pathology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany., Department of Pathology, Tata Memorial Centre, Homi Bhabha National Institute, India., Department of Pathology and Molecular Pathology, University Hospital Zurich, Switzerland., Heersink School of Medicine, The University of Alabama at Birmingham, Alabama, USA., Histopathology and Molecular Diagnostics, University Hospital Careggi, Florence, Italy., Department for BioMedical Research, University of Bern, Switzerland., Division of Pathology, Singapore, General Hospital, Singapore., Department of Surgical Pathology, Aichi Medical University Hospital, 1-1 Yazakokarimata, Nagakute, Japan., Skin and Renal Units, Royal Marsden NHS Foundation Trust, London, UK., Department of Laboratory Medicine and Pathobiology, University of Toronto, Canada., Pathology and Laboratory Medicine, Tufts Medical Center, Boston, Massachusetts, USA., Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada.