Spindle-cell ameloblastic carcinoma: A case report with immunohistochemical, ultrastructural, and comparative genomic hybridization analyses.

Spindle-cell ameloblastic carcinoma is a classification proposed for a group of rare odontogenic carcinomas with sarcomatoid components and is distinguished from odontogenic carcinosarcoma. We report a case of spindle-cell ameloblastic carcinoma of the right mandible that occurred in a 67-year-old Japanese man. Growth of the tumor was destructive, there was extensive lung metastasis, and the outcome was unfavorable. Ultrastructural and immunohistochemical examination showed the spindle-cell component of the tumor to be epithelial in character. A gain of 5q with amplification of 5q13 was detected in the tumor by comparative genomic hybridization.