Case Number : Case 2712 - 27 November 2020 Posted By: Dr. Richard Carr

Seborrheic Keratosis, Inflamed

Seborrheic Keratosis, agree. 

seb keratosis but anything from Dr Carr i am scared  whether i am missing SCC

Looks SK to me. Let's see what Dr. Carr tells us about this case. 

What about the IHC?

p53 looks like a wild type. Am I wrong?

EVG - no entrapment is typical of in situ lesions and SEBK. p16 is mosaic - often a little patchy in SEBK. p53 is wild type. Note lack of moderate or strong staining in the mature squamous component. Ki67 can be quite high and appear thickened in SEBK (a basal cell proliferation) but completely spares the maturation in the squamous component.

I reported this as SEBK. The nuclear cytoplasmic ratio was a little high so just to be sure I did the IHC to r/o SEBK-like bowenoid lesion. The laminated orthokeratin is very typical and I suspect the lesion was previously traumatised (note the more compact horn superficially with blood extravasation.

Dear sir, p53 wild type i understand, is p16 null type or reduced, can you please clarify

p16 is mosaic (wild). Can be a little patchy in SEBK and benign lesions.