Sebaceoma
Benign tumor with sebaceous differentiation
Unlike sebaceous adenoma, sebaceoma is composed of more than 50% basaloid cells intermixed with well-differentiated sebocytes
Sebaceoma
LEGEND
Composed of >50% basaloid cells
Sebaceoma
LEGEND
Classic appearance of a sebocyte nucleus being “indented” inward due to the mass effect of lipid vacuoles—this is not considered cellular atypia
Sebaceoma
LEGEND
Some cellular atypia and scattered mitoses may be present
Sebaceoma
As with sebaceous adenoma, sebaceoma is frequently associated with Muir-Torre syndrome
Loss of MSH-6 is observed (highly suggestive of Muir-Torre syndrome)
Immunohistochemistry for MLH1 and MSH2 is preserved
