A case of malignant clear cell hidradenoma

A 78-year-old man presented with a soybean-sized nodule on his occipital area with no symptoms for more than 1 year and enlarged for 3 months. A biopsy was carried out in another hospital, but the diagnosis was unclear. The lesion relapsed 2 months after biopsy. The lesion was surgically removed. The pathologic diagnosis was malignant clear cell hidradenoma. The patient died half year later after removal of the lesion. The exact cause of his death was not determined.