Surgical reintervention in acromegaly: is it still worth trying?

Background And Objective: There has not been a formal evaluation of how frequently and to what extent surgical reintervention in patients with persistently active acromegaly may achieve significant, albeit incomplete, reductions in growth hormone (GH) and insulinlike growth factor-I (IGF-I) levels. Of importance, recent studies suggest that the response to radiotherapy and pharmacotherapy is better with lower degrees of hypersomatotropism. The objective of this study was to evaluate the outcome of surgical reintervention in patients with active acromegaly at our institution between 1995 and 2005.

Methods: We retrospectively evaluated the outcome in 53 patients with active acromegaly (49 with macroadenomas) who underwent a second operation a mean of 24.1 +/- 25.2 months after the first intervention. Basal and postglucose GH as well as IGF-I levels were analyzed at diagnosis and after the first and second pituitary procedures.

Results: Basal GH decreased in 38 patients (72%): to <10 ng/mL in 17 and to <2.5 ng/mL in 11. The mean IGF-I index and basal GH decreased significantly after surgical reintervention: 1.7 +/- 0.4 to 1.4 +/- 0.4 (P = .0001) and 13.0 +/- 12.8 to 8.3 +/- 11.3 ng/mL (P = .0001), respectively. Some decrement in IGF-I was observed after surgical reintervention in 30 patients (57%), being greater than 30% in 9 (17%). Only 5 patients (9%) achieved complete biochemical cure (normal IGF-I and a postglucose GH level of <1 ng/mL). Reoperation achieved a significant decline in basal and postglucose GH levels as well as in IGF-I index only in patients with noninvasive macroadenomas.

Conclusion: Pituitary surgical reintervention in patients with acromegaly results in a low percentage of biochemical cure. If a remnant of a noninvasive macroadenoma is visible and accessible, however, such a procedure may significantly reduce GH and IGF-I levels.