Massive hyperplasia of testicular adrenal rests in a patient with Nelson's syndrome.

The case of a 23-year-old man with Nelson's syndrome is presented. He had undergone bilateral adrenalectomy at age 15 years for Cushing's syndrome. Postoperatively, his cushingoid features resolved; however, 13 months later, he became hyperpigmented and showed radiographic evidence of sellar enlargement and midline expansion of the sellar floor. In 1972, he received radiation therapy to the pituitary gland. He underwent transsphenoidal hypophysectomy in 1974 and 1975 for recurrent pituitary adenoma, and recurrent Cushing's syndrome developed concomitantly with bilateral firm testicular masses in 1978. External scanning with NP-59 localized steroid production to the testes, and bilateral orchiectomy was performed. Immunohistochemical studies of the pituitary tumor confirmed the presence of adrenocorticotropic hormone, and morphologic and ultrastructural examinations of the testes supported the adrenal nature of the testicular tumors.