Giant Mixed Tumor of the Skin Affecting the Hemiface.

Mixed tumor of the skin (MTS) is a rare skin adnexal neoplasm occurring in sweat glands. It is usually benign, measures 0.5 to 3 cm, and presents as a slowly growing, painless, firm nodule commonly in the head and neck regions. Owing to its rarity and lack of distinctive clinical manifestations, confirmative diagnosis is made on the basis of its pathologic features. Malignant MTS also develops de novo or from preexisting benign MTS even though they occur rarely. It should be excised completely to exclude malignant potentials. Herein, we report a 35-year history of a giant MTS of eccrine type measuring approximately 10.5 × 6.5 cm on the right hemiface of a 91-year-old woman, which is the largest facial MTS reported in the literature so far, to the best of our knowledge.