Ultrasound Characterization of Spiradenoma: Case Report and Literature Review

Spiradenomas are rare adnexal neoplasms that clinically mimic other cutaneous entities, such as epidermoid cysts and basal cell carcinomas. Although ultrasound diagnosis of common cutaneous tumors has significantly evolved over the last decades, the sonographic presentations of spiradenomas have been scarcely described. This study includes a case report and systematic review of previously reported sonographic characteristics of spiradenomas. A comprehensive search of the Pubmed/MEDLINE database identified studies with histological confirmation and ultrasound characterization of spiradenomas. Eight articles, comprising seven case reports and one case series with eight cases, were included. Data on clinical, demographic and sonographic features were extracted and analyzed. On B-mode ultrasound, spiradenomas appeared as well-defined, multilobulated, heterogeneous, hypoechoic masses located within the dermis and/or hypodermis, with posterior acoustic enhancement. Color Doppler imaging showed increased intralesional vascularization without anarchic pattern. The identified features helped differentiate spiradenomas from similar conditions, potentially reducing misdiagnoses, and optimizing management.