Spindle Cell Variant of Ameloblastic Carcinoma: Another Example in a Japanese Male.

Spindle cell variant of ameloblastic carcinoma (SpCAC) is a rare subtype of ameloblastic carcinoma. Herein, we describe an additional case of SpCAC of the mandible of a 76-year-old Japanese male. We discuss diagnostic problems we encountered in this case, focusing on unusual expression of myogenic/myoepithelial markers, such as smooth muscle actin and calponin.