PRIMARY LIPOSARCOMA OF THE SKIN - A RARE NEOPLASM WITH UNUSUAL HIGH-GRADE FEATURES

Liposarcoma is the most common soft tissue sarcoma in adults. It prese nts in three main forms: well-differentiated liposarcoma (which includ es adipocytic, sclerosing, inflammatory, spindle cell, and dedifferent iated subtypes), myxoid/round cell liposarcoma, and pleomorphic liposa rcoma. Anatomic distribution depends largely on histologic subtype, bu t the deep soft tissue of the extremities and the retroperitoneum are most frequently affected. Whereas it is accepted that liposarcoma rare ly occurs in the subcutaneous soft tissue, the dermis seems to represe nt an exceedingly rare site of occurrence. The clinicopathologic featu res of a series of seven primary cutaneous liposarcomas (two atypical lipomatous tumors/well-differentiated liposarcomas, one myxoid/round c ell liposarcoma, and four pleomorphic liposarcomas) are analyzed here. Clinically, all of the patients were adults (four men, three women) w ith a median age of 72 years, and four of seven cases arose on the sca lp. Local recurrences occurred in two patients, but no distant metasta ses or disease-related deaths have been observed. Although follow-up i s relatively short, it appears that, exceptionally, liposarcoma occurs primarily in the skin and, despite an apparent tendency to show high- grade morphologic features, it seems to exhibit relatively indolent cl inical behavior in this location.