Question: I have had two transsphenoidal surgeries, followed by removal of my adrenal glands, and now have Nelson's. What would be the treatment of choice, complete removal of my pituitary gland, radiation, or both?

Answer: Nelson's syndrome represents the enlargement of an ACTH secreting pituitary tumor following removal of both adrenal glands. Initially described in 1958, this problem is now relatively unusual since therapy is usually directed at the pituitary gland. However, when pituitary surgery is unsuccessful a bilateral adrenalectomy may be necessary and regrowth of the pituitary tumor may occur. If you have significant enlargement of pituitary tumor visible on MRI and if the tumor is near the optic nerve, another pituitary operation followed by radiation therapy would be a very reasonable approach. On the other hand, if the pituitary tumor is relatively small and not invasive, it may be possible to take a more conservative approach with MRI studies at six month intervals to assess the rate of tumor growth. If the tumor is not growing and plasma ACTH levels remain relatively stable, no further surgical intervention may be necessary. At this point, some authorities would also offer treatment with either conventional radiation therapy or possibly the newer gamma knife radiation therapy. Personally, I am not an enthusiastic supporter of primary radiation in cases such as this without surgical removal of all radiologically evident pituitary tumor.