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Q&A Sessions: Pituitary Adenoma

John Y.K. Lee, MD, Assistant Professor of Neurosurgery, is the Director of the Penn Center for Cranial Nerve Disorders and a national leader in treating cranial nerve disorders.

mt asks:
I had transphenoidal surgery to remove a pituitary adenoma a year ago with a pathology report of immunoreactivity for synaptophysin and ACTH. MY follow up MRI's in March showed that there is residual of the tumor, July and October MRI's show it measures slightly larger. I am diabetic and my sugar has been high since my surgery. I have been trying different meds and insulin and am concerned if the gamma knife will effect my sugar negatively. I had elevated blood levels in June of ACTH and Cortisol which indicated possible Cushing's Disease. I have since had two 24 hour urine test for cortisol and creatine levels which came out negative. So if it is not Cushings they want to do gamma knife. Is this my best option?

Dr. Lee responds:
Gamma Knife Radiosurgery can be an effective way to control pituitary adenomas.

NancyPittsburgh asks:
Does the Gamma Knife procedure do well in prolactin adenomas? What are the side effects of using the Gamma Knife?

Dr. Lee responds:
Hormone-secreting tumors can be controlled in slightly more than 50% of cases. Side effects include panhypopituitarism and very low risk of optic nerve injury.

Nancy asks:
My neurologist recently recommended Gamma Knife for a pituatary adenoma, which has not decreased in size the past six months on bromocriptine. I have been having headaches which are getting worse. My prolactin was 114 six months ago when I had a transient ischemic attack, went down to 17, but has now gone up to 43.

I would like to see a physician regarding this problem. If Gamma Knife is recommended, what is the percentage of success with this, the side effects, etc? I read your q/a but didn't see any questions regarding this issue. Please advise me. Thank you!

Also, what are the risk factors of the Gamma Knife when wanting to take care of a pituitary tumor (prolactinoma)? What are the after effects of the Gamma Knife? Do you see immediate results or gradual ones? Can the radiation cause burning problems?

Dr. Lee responds:
The first line approach to the treatment of pituitary adenomas is usually surgical, via transphenoidal resection. If the tumor can be completely resected, this provides the fastest relief of hormone overproduction. If surgery cannot completely extirpate the tumor, then Gamma Knife radiosurgery is an excellent option.

Success rates in stopping hormone overproduction are modest. In addition, results can take several months to years. Side effects are uncommon but include panhypopituitarism, visual deficits, and rarely facial numbness.

If you would like to discuss this further, please call 800-789-PENN (7366) and ask to be connected to Dr. John Y.K. Lee's office. You can also request an appointment online.

Julma asks:
My daughter was diagnosed with a pituitary adenoma at age 17. She is 23 now and the adenoma has grown and is causing not only milk production but painful menstrual periods due to over ovulation. We read about the Gamma Knife and want to know if this could be a good alternative to her Dostinex treatment of 5 years?

Dr. Lee responds:
Gamma Knife can be very effective in treating functioning pituitary adenomas like prolactinomas. Although the tumor control rates can be very good, the hormone control rates tend to be modest in the 50-60% range. I would be happy to see her in consultation.

If you would like to schedule an appointment, please call 1-800-789-PENN (7366) or request an appointment online.

MichaelR asks:
I've had to Gamma Knife surgeries to arrest GH production in a residual pituitary tumor. Now it's back: IFG-1 is elevated and I'm experiencing double vision in one eye. Is it safe to have a third surgery?

Dr. Lee responds:
A third Gamma Knife procedure for residual pituitary adenoma would be unusual, but depending on its location, it could be done if the growth is located distant to the first two.

Dorota asks:
At age of 18 I was diagnose with tumor on pituitary gland. I'm 31years old now. Last MRI shows tumor 2.8cm in height and 1.7cm in approximate diameter. The orbits show no abnormality. Would you recommend surgery?

Dr. Lee responds:
The management of pituitary tumors is complex and requires a careful analysis of endocrine, visual and imaging findings.


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Need an appointment? Request one online 24 hours/day, 7 days/week or call 800-789-PENN (7366) to speak to a referral counselor.

Gamma Knife and Leksell Gamma Knife are U.S. federally registered trademarks of Elekta Instrument S.A., Geneva, Switzerland. Photo credits: Susan Pardys, Elekta, Inc.

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