Off-Clamp Laparoscopic Partial Nephrectomy for a Fat-Poor Angiomyolipoma Arising from the Renal Capsule: A Case Report

Figure 4

Histopathological examination. (a) The tumor is contiguous with the renal capsule (H&E staining, ×40). (b) Both epitheloid and spindle cells proliferate in an interlacing fascicular arrangement. No fat cells are present (H&E staining, ×100). (c) The epitheloid cells are diffusely and strongly positive for α-smooth muscle actin (×100). (d) The spindle cells are focally and weakly positive for HMB-45 (×100).