Ultrasonic manifestation of dermatofibrosarcoma protuberans and differential diagnosis from superficial venous malformation: A retrospective study

Objective Dermatofibrosarcoma protuberans is a low-to-intermediate–grade malignancy with high postoperative recurrence risk. It is often misdiagnosed as superficial venous malformation due to nonspecific manifestations and clinical features similar to those of other soft tissue tumors. Ultrasound examination is crucial for dermatofibrosarcoma protuberans evaluation; however, its value in differentiating dermatofibrosarcoma protuberans from superficial venous malformation remains underinvestigated. Methods This retrospective study analyzed and compared the clinical and ultrasonographic features between 41 histopathologically confirmed dermatofibrosarcoma protuberans cases and 41 superficial venous malformation cases. Clinical data included sex, age, tumor size, and location. Ultrasound findings were categorized into five types, and the following features were evaluated: shape, boundary, pattern, invasion depth, and vascularity. Results The dermatofibrosarcoma protuberans tissues had significantly larger maximum diameters than superficial venous malformations ( p < 0.05). Anatomically, dermatofibrosarcoma protuberans predominantly occurred on the trunk, while superficial venous malformations were more common on the extremities ( p < 0.05). Dermatofibrosarcoma protuberans tissues mostly invaded both dermis and hypodermis, whereas superficial venous malformations primarily involved the hypodermis (p < 0.05). Dermatofibrosarcoma protuberans tissues had clearer boundaries ( p < 0.05) and were more likely to show hyperechoic cord-like structures (type 4), while superficial venous malformations frequently presented network structures (type 3) ( p < 0.05). Conclusions Ultrasound can provide valuable morphological features to assist in the differential diagnosis of dermatofibrosarcoma protuberans and superficial venous malformation, improving preoperative assessment accuracy and guiding treatment planning.