Malignant evolution of an ACTH-producing pituitary tumor treated with intrasellar implantation of 90Y. Case report and review of the literature.

A case of pituitary carcinoma is here presented, together with a review of the 25 cases so far reported in the literature. After a long-standing history of Cushing's disease, treated with interstitial pituitary irradiation and total adrenalectomy, Nelson's syndrome developed due to a pituitary neoplasm that finally spread through the subarachnoidal space, bringing the patient to death. The possible long-term role of surgery and radiotherapy in switching an aggressive behavior is also discussed.