[Two cases of adrenal myelolipoma diagnosed by ultrasonically guided percutaneous biopsy]

We report 2 cases of adrenal myelolipoma which were diagnosed definitively by ultrasonically guided percutaneous biopsy to waive surgery. In case 1, a 39-year-old man presented with abdominal pain. A right adrenal mass was detected by abdominal ultrasonography. In case 2, a 64-year-old man presented with nocturia. A space-occupying lesion above the left kidney was detected by excretory pyelography. Both cases were suspected of adrenal myelolipoma by ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI). The tumor size was 4 x 4 x 3 cm and 5 x 4.5 x 4 cm in cases land 2, respectively. In both cases percutaneous needle biopsy using ultrasonically guided puncture was performed. Histology showed a complex of hematopoietic and adipose tissues, corresponding to adrenal myelolipoma. The course has been uneventful without surgery for 58 months and 24 months, respectively. Percutaneous adrenal biopsy was useful to establish the definitive diagnosis and to select treatment options.