Two Cases of Adrenal Myelolipoma

We report myelolipoma found in two patients, of whom one had hormonal abnormalities related to adrenal function. The first patient was a 36 year‐old woman, who was found incidentally to have a left adrenal tumor by CT scan during admission for treatment of Guillain Barre syndrome. Obesity, hirsutism and osteoporosis were also evident, and the patient was forwarded for additional endocrine function analysis, which revealed elevation of serum cortisol, urine 17 OHCS and 17 KS, and a decreased level of ACTH. These abnormalities returned to normal after excision of the tumor. Pathologically, the tumor was composed of mature fat cells and hematopoietic components, and was diagnosed as myelolipoma. The second patient was a 63 year‐old woman, who was receiving follow‐up care for hyperthyroidism. A right adrenal tumor was noted incidentally in a routine examination by CT scan. Endo‐crinologically, she was found to have no abnormalities of adrenal function. The tumor was excised, and diagnosed pathologically as myelolipoma, being composed of mature fat cells and hematopoietic components. Generally, although most rnyelolipomas have no endocrine function, our first patient showed features of Cushing's syndrome. Thus it is suggested that an interrelationship may exist between myelolipoma and endocrinological alteration. Acta Pathol Jpn 42: 221 226, 1992.