Atypical Lipomatous Tumor/Well-Diff Liposarcoma : Sclerosing

Sclerosing atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL):The sclerosing subtype is almost always deep seated and found in the paratesticular region, retroperitoneum and sometimes in the mediastinum. There is a dominant fibrotic component consisting of broad sheets or intersecting trabeculae of spindle cells with atypical, bizarre, hyperchromatic nuclei in a fibrillary or sclerotic collagenized background. The fibrotic areas may contain no fat or just scattered fat cells. Lipoblasts are usually rare or absent in this pattern and the diagnosis rests on identifying atypical stromal cells.