Sebaceous Carcinoma or BCC with sebaceous differentiation? No dermal mucin around basaloid infiltrating epithelial aggregates. No stromal-epithelial clefts. Only focal palisading, and atypia that exceeds the expected degree on a BCC. But there isn't the in situ Pagetoid spreading expected in Sebaceous Carcinoma, so I find this case difficult.

Favor Sebaceous Carcinoma. 

Ductal differentiation makes me think of porocarcinoma.

Sebaceous carcinoma

Sebaceous Carcinoma (not a easy case i think)

Sebaceous carcinoma.

The tumor cells are arising from basal layer, basaloid pattern. There are areas showing clear cell changes, but SGC usually shows severe atypia. second SGC in lower lid is uncommon

BAsal cell carcinoma

High powers are not great but looks to have the squared of nuclei sign, and focally the applique sign (peritumoural subnecrosis), published by Kazakov's group for sebaceous carcinoma.

Site & other morphology obviously good for the diagnosis too.

Squared-Off Nuclei and "Appliqué" Pattern as a Histopathological Clue to Periocular Sebaceous Carcinoma: A Clinicopathological Study of 50 Neoplasms From 46 Patients.

THANKS for this comment, Richard. 

learning point sir

This is a sebaceous carcinoma. Thank everyone for the insightful discussion. Dr. Carr, thank you for the reference!

Sebaceous carcinoma.. nice case.

NICE CASE AND NICE LEARNING POINTS

Lovely :-)