News - A Report from the Pituitary Congress Meeting

The Eighth International Pituitary Congress was held June 22-25 in New York City. Sponsored by the Pituitary Society (www.pituitarysociety.org), the program was entitled Pituitary tumors: Back to basics. The scientific program included oral presentations and poster sessions on all types of pituitary tumors, including those causing Cushing's. There were many very excellent presentations on the latest in the diagnosis and treatment of pituitary tumors as well as new developments in understanding how and why pituitary tumors form.

Dr. Lynnette Nieman (NIH) presented "The Diagnosis of Cushing's Disease" which covered the latest available testing data for differentiating Cushing's disease (caused by a pituitary tumor) from an ectopic (not pituitary) ACTH secreting tumor. Petrosal sinus sampling remains the best available test for distinguishing the two. In contrast, differentiation using the dexamethasone suppression test and the CRH test, remains difficult unless both tests are positive for Cushing's disease. Dr. Nieman presented some new data using jugular venous sampling that looked very promising when the results were used in conjunction with the dex suppression and CRH test. Jugular venous sampling is a less invasive procedure than petrosal sinus sampling and should eventually be available in a number of facilities not equipped to conduct petrosal sinus sampling. The current data illustrated that the results from jugular sampling, combined with the results of the dex and CRH tests could correctly identify Cushing's disease in 60-70% of patients, which means that only 30-40% of patients would need to undergo the more invasive petrosal sinus sampling test at specially equipped facilities.

Dr. Anne White (Endocrine Sciences, University of Manchester, UK) presented an approach to differentiating between Cushing's disease and ectopic ACTH secreting tumors using a blood test. The body makes the short peptide hormone ACTH by cutting a long peptide into smaller pieces. Called processing, this results in several shorter peptides, one of which is ACTH. Processing normally occurs in pituitary cells and ectopic ACTH secreting cells do not seem to process as well, leaving an abundance of longer peptides that can be measured in the blood. The test kit is currently commercially available for research purposes only (www.idsinc.us.com 480-836-7435 or www.idsltd.com ). Hopefully, clinical trials will begin soon and this test will become a diagnostic tool in the future.

In a session dealing with replacement therapy, Dr. George Chrousos from NIH discussed glucocorticoid replacement therapy, highlighting the differences between the different glucocorticoids. In the end, there remains no good way, other than how the patient feels, to tell if replacement levels are optimal.

In the same session, Dr. Anne Klibanski, (Neuroendocrine Unit, Harvard) discussed the replacement of sex steroids (estrogen, progesterone and testosterone) in hypo-pituitary men and women. New concerns raised over estrogen replacement in post-menopausal women have created a controversy. However, data available to date support estrogen/progesterone replacement in hypo-pituitary, pre-menopausal women in whom estrogen and progesterone should be present. Testosterone replacement in deficient men has been shown to increase bone mineral density and has other effects such as improvement in libido, depression, cognitive function, and body composition. The effects of testosterone are currently under study in both men and women. During a lunchtime seminar, Dr. Karen Miller, (Massachusetts General Hospital, Boston) presented a wonderful overview of both estrogen/progesterone and testosterone replacement in hypo-pituitary women. Dr. Miller is also involved in a conducting a current research study for testosterone replacement in women.

Growth hormone replacement was discussed by Dr. Shalet (Christie Hospital, Manchester, UK). GH deficiency still appears to be one of the first pituitary deficiencies to appear. In patients with 2 to 3 other pituitary deficiencies, GH deficiency is present in about 90-95% of those patients.

Dr. Cappabianca (Neurosurgeon at Uiversità degli Studi di Napoli Federico II, Naples, Italy) presented the results of 203 patients operated on using endocscopic endonasal pituitary surgery from 1997 through 2002, as opposed to the traditional transsphenoidal approach. Based on comparisons to large studies published on transsphenoidal surgery, the endoscopic approach currently appears to offer less trauma to the nasal structures, fewer complications, an easier approach to a second surgery and an approximately equal outcome of tumor removal. Dr. Cappabianca stressed that this is a newer, less proven technique with a surgical learning curve and that since the technique has not been in use for many years, long-term cure information is still lacking.