Histological examination of a renal leiomyoma reveals fusiform to spindle shaped cells with positive immunohistochemical staining for smooth muscle markers (desmin, caldesmon, and SMA) and negative staining for HMB-45 and cathepsin K. It should not reveal atypical nuclei, mitotic figures, or microscopic necrosis [13]. Here, CALD1 is linked to renal leiomyoma.