[A case of adenomyelolipoma]

We report case of adenomyelolipoma. CT and MRI revealed a large, capsulated, septated adrenal mass with abundant fat tissue. However, enhancing components were demonstrated at the capsule and septations on angiography. On the pathological study, the capsule and septations consisted of adrenal adenoma and the tumor contained various forms of myelolipomatous tissues. These myelolipomatous tissues were classified into 4 groups. Type I: Scattering of fat cells and hematopoietic elements without coalescence. Type II: Collection of myelolipomatous tissue with unclear margin or small myelolipomatous tissue that cannot be classified as type I or III. Diameter of the lesion is less than 1 cm. Type III: Collection of myelolipomatous tissue with clear margin or replacement of cortical nodule. Diameter of the lesion is less than 1 cm. Type IV: Collection of myelolipomatous tissue. Diameter of the lesion is equal to or greater than 1 cm. We defined adenomyelolipoma as a lesion combining adrenal adenoma (or hyperplasia) and various forms of myelolipomatous tissues (type I-IV) in view of the strong relationship between adrenal adenoma (or hyperplasia) and myelolipomatous tissue.