Who Classification Of Skin Tumours Apr 2026

: Progress in identifying gene fusions (e.g., YAP1::MAML2 in poromas) has enhanced diagnostic accuracy for sweat gland and hair follicle tumours.

: A new chapter focusing on the adverse prognostic implications of systemic cancers metastasizing to the skin. WHO Classification of Skin Tumours

: The term "variant" is now reserved strictly for genetic alterations in DNA sequences, rather than being used to describe morphological subtypes. : Progress in identifying gene fusions (e

The (5th Edition, 2025) is the authoritative global standard for diagnosing and categorizing cutaneous neoplasms. Also known as the "Blue Books," this edition shifts toward a more integrated, multidisciplinary approach that combines traditional histopathology with advanced molecular genetics and immunohistochemistry. Key Structural & Conceptual Changes The (5th Edition, 2025) is the authoritative global

: The 5th edition (WCT5) organizes tumours into a rigid hierarchy: Site → Category → Family → Type → Subtype .