Surgical treatment of invasive pituitary adenomas (somatotropinoma or corticotropinoma)

AIM OF THE STUDY: To evaluate efficiency of the transcranial epidural approach in the treatment of invasive GH- or ACTH-secreting pituitary adenomas with extension to the cavernous sinus. MATERIAL AND METHODS: During the past two years (from January 2000 to December 2001) 14 patients with invasive GH- or ACTH-secreting pituitary adenomas extending to the cavernous sinus were operated on using the transcranial epidural approach. Our experience is based on an analysis of 12 patients with GH-secreting tumors and 2 patients with ACTH-secreting adenomas. The patients' mean age was 45.36 years (range 28-66, SD +/- 10.26 years). Parasellar extension of the tumor was measured using the Knosp scale--in all the cases there was an extension to the cavernous sinus, in stage III (4 patients) or stage IV (10 patients). RESULTS: In none of the cases a total surgical removal of the invasive GH-secreting adenoma was attained (according the following cure criteria: basal serum GH level below 2.5 micrograms/l, OGTT < 1 microgram/l, normal sex- and age-related IGF-I level). In four patients the surgery resulted in a reduction of the basal serum GH level to below 5 micrograms/l (their postoperative mean serum IGF-I level was 530 micrograms/l--significantly lower, but still abnormal, p < 0.05). In a single case of a female patient the basal serum GH level was below 10 micrograms/l, while in other 7 patients the GH level remained above 10 micrograms/l. Remission (normalization of 24-hour urine-free cortisol (UFC) and its metabolites) was achieved in one patient with the Cushing disease. There were no complications involving case fatality. A transient deterioration of the third cranial nerve function observed in one patient disappeared within 3 months from the surgery. There was no deterioration of pituitary function and no cases of diabetes insipidus in our group. CONCLUSION: Transcranial epidural approach is an alternative to radiotherapy and/or prolonged medication in the treatment of invasive GH- or ACTH-secreting pituitary adenomas.