Fibrosarcomatous dermatofibrosarcoma protuberans with giant rosettes

A rare case of dermatofibrosarcoma protuberans, which contained low-grade fibrosarcoma with giant rosettes in its recurrence areas is described. The giant rosettes lying in the fibrosarcomatous area produced a pattern similar to that of so-called hyalinizing spindle cell tumor with giant rosettes. The transitions between the tumor components were gradual, and both primary and recurrent lesions showed diffuse immunoreactivity for CD34. The presence of giant rosettes in fibrosarcomatous areas of dermatofibrosarcoma protuberans suggests a possible histogenetic relationship between fibrosarcomatous areas of DFSP and hyalinizing spindle cell tumor with giant rosettes.