PMC4335625_01
Longitudinal sonogram of the left kidney.. Notes: Longitudinal sonogram shows a 3.2 cm x4.5 cm liquid dark area (C) in the lower pole of the left kidney (LK). An irregular 2.4 cm x2.1 cm, slightly hyperechoic mass (N) is visible in the liquid dark area without acoustical shadowing, which was extensively connected to the left kidney.
ott-8-445Fig1.jpg
PMC4335625_01_ott-8-445Fig1.jpg
f1-ott-8-445
An irregular 2.4 cm x2.1 cm, slightly hyperechoic mass was visible in the liquid dark area without acoustical shadowing, which was connected to the left kidney extensively (Figure 1).
CT images of the left renal tumor.. Notes: (A) Unenhanced CT scan shows a well-defined, high-density mass measuring 3.7 cm x3.3 cm (long arrow) in the lower pole of the left kidney, with an irregularly shaped lower attenuation area (short arrow) in the mass. (B-D) Enhanced CT scan shows that the tumor appears to have no enhancement in the peripheral portion (white arrow), and progressive enhancement in the central portion (black arrow).. Abbreviation: CT, computed tomography.
ott-8-445Fig2.jpg
PMC4335625_01_ott-8-445Fig2.jpg
f2-ott-8-445
An unenhanced CT scan showed a well-defined, high-density mass measuring 3.7 cm x3.3 cm in the lower pole of the left kidney, with an irregularly shaped lower attenuation area in the mass (Figure 2A). Progressive enhancement in the central portion was observed, with 46 Hounsfield units (HU) before contrast enhancement, and 64 HU, 81 HU, and 82 HU on the cortex-phase, medullary-phase, and delayed-phase images, respectively (Figure 2B-D).
Microscopic appearance of MA.. Notes: (A) A histological specimen shows the homogeneous round or ovoid tumor cells mainly composed of tiny tubules and papillae, accompanied by very scanty stroma (HE x200); (B and C) the tumor cells are negative for WT1 and CD57 (SP x200), respectively.. Abbreviations: MA, metanephric adenoma; HE, hematoxylin and eosin; SP, streptavidin-peroxidase.
ott-8-445Fig3.jpg
PMC4335625_01_ott-8-445Fig3.jpg
f3-ott-8-445
The histological features of the tumor were characteristic for MA (Figure 3).