Dedifferentiated chondrosarcoma of the ring finger: a case report of an exceptional surgical treatment and review of literature.

The DDCS is a rare, highly malignant tumor characterized by two distinct histopathologic components. The diagnosis is insidious, and the prognosis is poor. The therapy is primarily surgical. It is possible to associate chemotherapy if the nonchondrogenic component is a responder. Unfortunately, very few cases of DDCS of the hand are described in the literature. Therefore, few scientific comparisons are possible regarding diagnosis and therapy. For this reason, we decided to present a sporadic case of DDCS of the fourth finger of the left hand, presented with a seven months history of pain and swelling, which appeared after the treatment of recurrent enchondroma and was treated with amputation and complex reconstruction. To our knowledge, no similar cases have been previously reported in the literature.