CT features of renal epithelioid angiomyolipoma

Objective: To explore the CT features of renal epithelioid angiomyolipoma (EAML), and to improve the diagnosis of this disease. Methods: The clinical materials and image findings of 15 cases (8 female, 7 male) with renal EAML proved by pathologies were retrospectively studied. Plain and enhancement CT scan were performed in all 15 patients. Nine of the 15 cases were correctly diagnosed and the other were misdiagnosed as renal cell carcinoma (RCC) (n=5), renal oncocytoma (n=1). Results There were some distinctive findings of EAML: (1) Little hypodense or iso-high-density, well defined, round lesion with diameter of 2 to 5 cm. (2) The tumor may involve the medulla of kidney or grow out without haematuria. (3) Most lesions showed obviously uniformity enhancement at artery phase, with a few of them showed inhomogeneous enhancement. There were thickening and circuitous vessels in a few lesions. (4) Enhancement mode was quick-in and quick-out. Conclusions: CT findings combined with clinical materials have important value in making a correct diagnosis of EAML preoperatively. (authors)