Case Number : Case 2108 - 5 July 2018 Posted By: Dr. Hafeez Diwan

Endocrine mucin producing sweat gland carcinoma or, less likely, adenoid cystic carcinoma. I’d do CK7, ER, PR, synaptophysin, chromagranin.

If the lesion is not on the eyelid, adenoid cystic carcinoma (either primary or metastatic from a salivary gland tumour) is more likely. 

Looks like one of those mucinous carcinomas with more solid areas. Good to do a myoepithelial marker to look for an in situ component. Can have endocrine differentiation as suggested above.

The first figure shows a multinodular tumor . I think you can also see an elongated cystic duct lined by two or three cell layers. I think that ductal structure is benign, most likely eccrine in nature. The first two figures might also show mucin in the stroma (first I thought it was fat, but I think it's more likely mucin after i read other comments). The last picture shows fibrovascular core in the nodule, reminiscent of solid papillary carcinoma of the breast. Everytime I see a cutaneous tumor that looks like a solid papillay carcinoma of the breast , I think of endocrine mucin- producing sweat gland carcinoma.

I think one sees basement-like material in the tumor nests of adenoid cystic carcinoma, not fibrovascular cores. Besides, adenoid cystic carcinoma is composed of basaloid cells.

So-called Endocrine Mucin Producing Sweat Gland Carcinoma, with early stromal infiltration. I favor this diagnosis because of a distorted eccrine ductal structure between cribriform epithelial nodules in fig 1. 

Or polymorphus sweat gland carcinoma