Case Number : Case 1901 - 011 Sept - Dr Limin Yu Posted By: Guest

Large cells acanthoma 

also thought of large cell acanthoma

Bowen's disease with vacuolization of cells.

I'd have to go with Bowen's disease. May be pigmented Bowen's disease.

Large cell acanthoma is a controversial entity and one opinion is that it's a variant of Bowen's !!! Sanchez YE. Am J Dermatopath 1988; 10: 197-208

Find this very difficult. Not convinced of Bowen's. So will go with large cell acanthoma. 

I started with bowen's and moved to LCA. p16, Ki67 & p53 would usually sort this in most cases but favour LCA on the images here.

Thank everyone for the insightful discussion. I considered both SCCIS and Large cell acanthoma. Knowing that LCA is a controversial entity (some believe it is a variant of lentigo or SK), I still favor it. The significance of LCA is not to diagnose SCCIS on lesions like this.