Primary adenoid cystic carcinoma of the skin: a case report

Abstract

A 75-year-old male complained of a demarcated plaque on his left upper arm for 13 years. The patient underwent a surgery 7 years prior to the appearance of the palque. Dermatological examination revealed a dark red elevated plaque of 3.0 cm×3.5 cm×0.5 cm in size on the extensor side of the left upper arm. The plaque was firm and mild tenderness, with uniform color and poor mobility. Histology showed that the tumor was composed of myoepithelial and glandular epithelial cells arranged in cribriform and glandular pattern, with glandular and pseudoglandular lumens. Some areas appeared differentiation to sebaceous glands, infiltrative growth pattern and nerve invasion. Immunohistochemistry showed that tumor cells were CK-pan (glandular epithelial+), CK5/6(myoepithelial+), CD117(glandular epithelial+), CK7(glandular epithelial+), EMA(glandular epithelial+), P63(myoepithelial+), Ki-67 (15% positive rate within hotspot area). A diagnosis of primary cutaneous adenoid cystic carcinoma was made. Surgical excision was given, and no recurrence was observed during a 6-month follow-up.

Keywords

• primary
• skin
• adenoid cystic carcinoma