Dedifferentiated Liposarcoma : Clinical Features

Comments:
Clinical Features: Dedifferentiation is a late complication in the natural history of atypical lipomatous tumor/well-differentiated liposarcomas (ALT/WDL). The latency period is 7-10 years after the initial diagnosis but may be longer. Dedifferentiated liposarcomas (DLPS) account for about 18% of liposarcomas. The peak incidence is in the 7th decade. Both sexes are affected equally.

Deep-seated tumors located in the retroperitoneum are more likely to undergo dedifferentiation and account for 80% of DLPS. Less than 20% occur in the spermatic cord/paratesticular region (shown here), mediastinum, head and neck, and trunk. The risk of dedifferentiation in ALT/WDL of the extremities is quite low (5%) but cases have been reported.

Retroperitoneal DLPS often reach large size before they are discovered. The symptoms are related to the presence of a large abdominal mass. In the extremities (a rare location), the patients complain of a painless, slowly enlarging mass with a recent history of rapid growth.