Endocrine Abstracts

Introduction: Transsphenoidal adenomectomy is the treatment of choice in secreting pituitary adenomas with the symptoms of Cushing’s disease, acromegaly as well as few cases of Prolactinoma, which – due to resistance to pharmacological treatment – require surgery. The efficacy of selective adenomectomy ranges from 60 to 95%. It is the highest in patients with well-visualized by MRI microadenomas, lower in macroadenomas and the lowest when the surgery was performed without any changes in imaging techniques.

Due to complicated diagnostic procedures and the necessity of prolonged postoperative observation it is necessary to prove which hormonal laboratory findings drawn shortly after pituitary surgery could foresee the lasting remission. The early identification of a high risk of recurrence would allow to perform an immediate re-operation that increases the chance of cure during the same hospital stay.

We have examined 40 patients with secreting pituitary adenomas being prepared at our site to surgical treatment and followed up for the next 12 months. All patients were operated by the same neurosurgeon performing over 100 transsphenoidal surgeries per year.

All patients had blood draws for serum cortisol, GH or PRL performed on the first postoperative day and additionally FSH, LH, TSH. The same laboratory tests were taken after 6, 12, 24 weeks and 12 months after surgery.

The results of our study indicate that subnormal (<2.0 ng/ml) serum cortisol levels in the first postoperative day in CD can foresee lasting remission. In case of acromegaly, the low levels (<1.0 ng/ml) of serum GH can predict long-term remission. In patients suffering from Prolactinoma, we perform surgery only in tumors resistant to pharmacological treatment. The early results seem to be promising.

Conclusion: The early results show a correlation between low serum cortisol, GH and PRL levels in the 1st day after surgery and long term remission. It simplifies postoperative diagnostic procedures. In case of CD, we expect that the cut off point will be lower than 5 ng/ml – previously obtained in other studies. In addition, the early postoperative cortisol assessment allows to predict postoperative function of the pituitary–adrenal axis.