Porocarcinoma Arising in a Ganglion Cyst: A Case Report and Review of the Literature

ABSTRACT

Eccrine porocarcinoma is a rare malignant neoplasm of the eccrine sweat gland that often occurs in the lower extremities, and usually affects elderly individuals. Most cases of eccrine porocarcinoma arise de novo. We encountered a case of a large porocarcinoma arising in a pre-existing ganglion cyst in the knee. The malignant tumor was excised widely, and the defect was reconstructed using a free anterolateral thigh flap.