Sonographic Characteristics of Apocrine Hidradenoma of the Skin: A Case Report

Abstract

Nodular hidradenoma is a benign sweat gland-derived rare tumour. Histologically, these tumours can be classified into eccrine and apocrine subtypes. In most cases, the diagnosis is made after surgical excision and hidradenomas generally follow a benign course, although malignant transformation is also documented. We present here a new case of apocrine hidradenoma with lymph vessel permeation.
We describe the ultrasound findings of clear cell hidradenoma of the arm in an 82 year old man. The lesion involved the dermis and hypodermis and presented a well-defined oval structure with solid-cystic appearance that showed a hypoechoic rim and an inner mixed structure with hypoechoic solid nodule with marked vascularisation and anechoic lacunar fluid-filled cyst.
In comparison with other common cutaneous lesions, apocrine nodular hidradenomas present sonographic characteristics which may support their earlier and more precise sonographic diagnosis and also avoid clinical and dermatoscopic misdiagnosis.