A case of asymptomatic giant myelolipoma of the adrenal gland.

A 50-year-old man had a giant myelolipoma of the right adrenal gland, 30 x 25 x 23 cm in size, and 3,500 g in weight. The mass was hyperechoic with low echoic areas in part on US, heterogeneous with fat density tissues and tissues with density higher than fat on enhanced CT, heterogeneous with fat intensity areas on both T1- and T2-weighted MR images and with other areas of low intensity on T1-weighted images and high intensity on T2-weighted images due to myeloid tissues, and relatively hypervascular on subphrenic arteriography. This tumor was unique because, except for palpation of the mass on physical examinations, there were no symptoms such as abdominal pain due to hemorrhage, necrosis, or pressure on the surrounding structures despite its huge size.