Case Number : Case 2649 - 01 September 2020 Posted By: Uma Sundram

Looks like I'll have to open the batting, but, as happened frequently in my actual cricketting career, I risk getting out for a duck!

I see multiple anastomosing  bands of epidermally-derived cells, forming ductal structures and associated with an inflammatory dermal response.  There is evidence of necrosis in places.  The cytology of the tumour cells is difficult to see on these views.  However, the overall pattern suggests a diagnosis of low-grade eccrine porocarcinoma.

7 hours ago, Richard Logan said:

Looks like I'll have to open the batting, but, as happened frequently in my actual cricketting career, I risk getting out for a duck!

I see multiple anastomosing  bands of epidermally-derived cells, forming ductal structures and associated with an inflammatory dermal response.  There is evidence of necrosis in places.  The cytology of the tumour cells is difficult to see on these views.  However, the overall pattern suggests a diagnosis of low-grade eccrine porocarcinoma.

Agree! A minimally invasive porocarcinoma. 

eccrine duct adenocarcinoma

Agree with minimall inavsive porocarcinoma

When I look at the "infiltr ative glands" in the superficial dermis, I think I still see 2 layers: the inner secretory columnar cells and the outer flat myoepithelial / basal cells which make me wonder whether the glands are benign.  So I would offer another possibility in the differential diagnosis: eccrine adenomatous metaplasia. I probably would do some stains to see whether the basal / myoepithelial layer is still present in those glands.

It looks poroid and invasive (minimal?) so agree with Porocarcinoma

Yes, this was a difficult one. We thought we could see two layers in the dermis as well, so we went with poroma, rather than porocarcinoma. However, wide margins were taken of this lesion anyway, so both approaches are covered. 

Dear Dr. Sundram,

Have you seen a benign poroma excite such an inflammatory response before?

I think this is a case where the lesion failed to read the textbook. Looks benign to me though. "Benign acanthoma with tubular eccrine ductal differentiation"?