A CASE OF DUCTAL SWEAT GLAND CARCINOMA CONNECTED TO SYRINGOCYSTADENOMA PAPILLIFERUM ARISING IN NEVUS SEBACEUS

We report a case of a tumor arising in the preauricular region in a 50 -year-old woman. The histopathological findings revealed it to be a du ctal sweat gland carcinoma connected to a syringocystadenoma papillife rum (SCAP) arising in a nevus sebaceus. Mucinous stroma, considered to be deposition of hyaluronic acid, was also observed in the ductal car cinoma portion. The immunohistochemical and ultrastructural findings i n the ductal carcinoma were compared with those in the SCAP. The proli ferating cell nuclear antigen labeling index of the cells in the ducta l carcinoma was higher than that of those in the SCAP. Both the ductal sweat gland carcinoma and SCAP showed findings compatible with the du ctal segment of a sweat gland.