Factors affecting the outcome of surgical treatment of acromegaly

To assess the results of and factors associated with the outcome of surgery for acromegaly.

We retrospectively examined the medical records of acromegalic patients who underwent trans-sphenoidal adenomectomy at our hospital during the period of January 1991 through August 1997. Preoperative evaluations included measurement of basal serum growth hormone (GH), insulin-like growth factor-I (IGF-I), prolactin (PRL), GH response to oral glucose, and GH and PRL response to bromocriptine, as well as pituitary magnetic resonance (MR) imaging. Postoperative evaluations included measurement of basal serum GH and IGF-I concentrations, and pituitary MR imaging.

Thirty patients (14 men) with a mean age of 38 years were included. The mean follow-up period was 50 months (range, 15-90 mo). Ten of the 30 patients (33%) had early postoperative (1 mo after surgery) GH levels of less than 5 ng/mL. Twenty patients (67%) had final postoperative (last follow-up, 15-90 mo after surgery) GH levels of less than 5 ng/mL. Preoperative GH levels were positively correlated with early postoperative GH levels (r = 0.458, p = 0.011) and final postoperative GH levels (r = 0.479, p = 0.007). Early postoperative GH levels were also positively correlated with final postoperative GH levels (r = 0.595, p = 0.001). Tumor grade and stage were not significantly correlated with early or final postoperative GH levels. Thirteen of 21 patients (62%) who had postoperative MR imaging follow-up had residual tumor. There was no surgical mortality.

These results highlight that acromegaly is not easily treated with surgery alone. The preoperative GH level was associated with the surgical outcome.