Giant keratoacanthoma is an uncommon variant of keratoacanthoma, which may attain the diameter of several centimeters. Although keratoacanthoma usually undergo spontaneous resolution, giant keratoacanthoma can be invasive and destructive. A 49-year-ol...
Giant keratoacanthoma is an uncommon variant of keratoacanthoma, which may attain the diameter of several centimeters. Although keratoacanthoma usually undergo spontaneous resolution, giant keratoacanthoma can be invasive and destructive. A 49-year-old man presented with a 5-year history of multiple large hyperkeratotic and crusted plaques and nodules on the sun exposed areas such as face, ear, hand and forearm. Some lesions were involuted spontaneoulsy, whereas other lesions were rather enlarged. The biopsy specimen revealed horn-filled crater formation, epidermal extending like a buttress and eosinophilic glassy appearance in kertinocytic cytoplasm. In immunohistochemical stain, the Ki-67 staining was restricted to the basal layer. And p16 staining occurred more diffuse pattern. We treated them with acitretin and the lesions were almost cleared after 13 weeks. Herein we describe a case of multiple giant keratoacanthoma treated with acitretin.