Figure 6b: Leukemia and a small mass in a 46-year-old man. (a) Transverse T1-weighted MR image (5.9/1.9) reveals peripherally enhancing 2.1-cm mass in right renal upper pole (arrow) and perinephric stranding (arrowhead). (b) CT-guided percutaneous biopsy, shown on transverse CT image, was performed with a 25-gauge needle (arrow). Hematoxylin-eosin–stained cell block section (not shown) revealed acute and chronic inflammatory cells. (c) Photomicrograph shows fungal organisms (arrows). The patient was treated for renal candidiasis. (Methanimine silver stain; original magnification, x600.)