Case Number : Case 2577 - 22 May 2020 Posted By: Dr. Richard Carr

Rippled pattern of basaloid, germinal, mitotically active cells. 

No specialized, cellular stroma.

Some stromal mucinous material, but no epithelial-stomal retraction. 

No apoptotic bodies.

Some sebaceous differentiation.

I think this is a difficult case of Sebaceoma, on which the old diagnostic label of "sebaceous epithelioma" could be appropriate.

Agree with Vincenzo. When I see a ripple pattern I first think of a sebaceoma. For those wonder about a basal cell carcinoma, BerEP4 can help.

Yes. Ripple pattern-sebaceoma

Agree Sebaceoma 

sebaceoma

Brilliant. Unanimous for sebaceoma. Just a historical note that these lesions were frequently mis-diagnosed as rippled pattern trichoblastoma (share nodular profile, mainly basaloid "organoid" tumour and stromal clefts seen here). If you've seen one or two already this case becomes a quite simple spot diagnosis. I agree BerEP4 can be a very useful antibody (negative or minimal weak/moderate in sebaceoma compared with diffuse in BCC, patchy in trichoblastoma and frequently positive in sebaceous carcinoma) always run in combination with EMA (always completely negative in basaloid cells of BCC (limited to squamoid "keratotic"), differentiation, germinative cells of sebaceoma (highlights mature sebocytic cells mainly) and usually more widely positive in sebaceous carcinoma. This lesion lacks the papillary mesenchymal cell condensations typical of trichoblastoma.

Lovely case!