Case Number : Case 1516 - 15 April Posted By: Guest

Made me think of cystic hidradenoma with extensive papillary areas (both micropapillary and real papillae with sclerotic cores) 

Cystic hidradenoma with focal calcification,hyalinization and apocrine differentiation .

Hidradenoma

Hidradenoma.

Agree, nodular and cystic Hidradenoma with proeminent apocrine features.

Hidradenoma

nodulo-cystic hidradenoma with apocrine differntiation

agree

Yes well done all.

My report:

I agree this is a benign adnexal tumour of sweat gland origin and has features in keeping with hidradenoma. The lesion shows apocrine features and unusually papillary architecture with psammoma bodies.  I have not seen the latter previously in hidradenoma.

As you know, sweat gland lesions can show various differentiations. I did not see any worrying features for malignancy and the lesion appears to be excised with narrow connective tissue margins. I am sure a wait and watch policy can therefore be adopted.

IHC was performed as follows: p63 diffuse, sparing luminal apocrine cells only. p53 weak (wild), Ki67 very low < 1%; TTF-1 negative.