Finger chondroid syringoma as a hypoechoic subcutaneous nodule in ultrasound

Abstract

Chondroid syringoma (CS) is an uncommon, benign epithelial skin mixed tumor. It is often located in the head and neck and is unusual in other parts of the body. It may be seen as a skin or soft tissue tumor. We present findings on high-resolution ultrasound and histology in a case of benign CS located on the right index finger. High-resolution ultrasound showed a solid hypoechoic, well-defined subcutaneous mass, adjacent to the tendon. Complete surgical excision was performed, and histopathology demonstrated an apocrine mixed tumor (CS). Although CS histological findings are well described, radiological features have been reported only in few cases and mainly in magnetic resonance. Chondroid syringoma should be suspected by high-resolution ultrasound as a differential diagnosis for a solid slow-growing soft tissue nodule in a finger, especially if the lesion has no contact with the underlying tendon.