What made me think it was malignant transformation of a KA is that the regression crateriform area has different ihc pattern, with wt p16 and p53, and very low ki-67.

11.09.2025 05:49 — 👍 0    🔁 0    💬 2    📌 0

Do you think it is invasive or in situ? I struggle with this kinda"pushing" lesions...

10.09.2025 10:04 — 👍 0    🔁 0    💬 2    📌 0

P16

P16

P53

P53 (lost in the atypical zone)

Immuno. Ki-67 not pictured (was low on the crateriform area, and very high on the atypical zona).

I belive this is a SCC arising on a keratoacanthoma. What do you think @racarr51.bsky.social ?

10.09.2025 09:59 — 👍 2    🔁 0    💬 0    📌 0

Detail of the atypical area

10.09.2025 09:56 — 👍 0    🔁 0    💬 1    📌 0

@racarr51.bsky.social Lesion clinically suggestive of keratoacanthoma

10.09.2025 09:55 — 👍 2    🔁 1    💬 2    📌 0

Trichilemmal Carcinoma?

08.09.2025 11:44 — 👍 1    🔁 0    💬 1    📌 0

Yes, but the online version has now changed to the "print" versión, so there's no p16 anymore either :( fortunately I have your papers!

08.09.2025 09:29 — 👍 0    🔁 0    💬 2    📌 0

Hi! Why did they not include info and patterns of p16 in the print version of the WHO Skin blue book? There were some hints in the former beta version but no mention at all in the actual print version...

05.09.2025 09:25 — 👍 0    🔁 0    💬 2    📌 0