Acral dermatofibrosarcoma protuberans with myoid differentiation: a report of two cases

Dermatofibrosarcoma protuberans (DFSP) is a low-grade mesenchymal neoplasm with a tendency for local recurrence; it is rarely metastatic. Dermatofibrosarcoma protuberans typically arises in the trunk and proximal extremities. However, it can arise in unusual sites such as the hands and feet. Several variants have been described, including DFSP with myoid differentiation, which is very uncommon. This variant tends to be observed more with the fibrosarcomatous variant, and it can be either in the form of myoid bundles and nodules with no vascular relationship or represent hyperplastic blood vessels within the tumor. Here, we report two cases of DFSP with myoid differentiation (ordinary and fibrosarcomatous) on the foot. To the best of our knowledge, these cases represent the first two cases of acral DFSP with myoid differentiation.