SPINDLE-CELL LIPOMA IS STRONGLY CD34 POSITIVE - AN IMMUNOHISTOCHEMICAL STUDY

Spindle cell lipoma (SCL) is an uncommon soft tissue neoplasm that may provide diagnostic difficulty to the histopathologist. Four retrospec tively identified SCLs were evaluated immunohistochemically with a bro ad panel of antibodies (CD34, factor XIIIa, S100, actin and factor VII I). All four SCLs were strongly CD34 positive (95 to 100% of cells) an d focally factor XIIIa positive (average 16% of cells). Tumor cells we re S100, actin and factor VIII negative. Dermatofibrosarcoma protubera ns, neurofibroma, schwannoma and angiolipoma are CD34 positive tumors that have some similar histologic features to SCL and may be considere d in the differential diagnosis. Differentiation is possible using a b road panel of immunostains and routine diagnostic criteria.