Recent results of secondary transnasal surgery for residual or recurring acromegaly

The results of secondary surgery for either residual or recurring acromegaly have been reported to be unfavorable. To evaluate the effectiveness of recent techniques of secondary transnasal microsurgery, we analyzed the surgical results of remnant or recurring acromegaly in patients who underwent secondary transnasal surgery from 1990 to 1996.

Secondary transnasal explorations were performed in 28 acromegalic patients (mean age+/-standard error, 39+/-2.3 yr) who had been previously treated with microsurgery (patients at our institutions, n=5; patients at other institutions, n=23). For most of these patients, medical treatment after primary surgery was unsatisfactory. Magnetic resonance imaging demonstrated 18 transnasally resectable tumors (64.3%) and 10 nonresectable grossly invasive tumors (35.7%). Surgical indication was based on elevated plasma growth hormone (GH) levels and evidence of tumor revealed by magnetic resonance imaging.

Intraoperative GH measurement was performed in all patients. In 13 of 18 patients with resectable tumors, the surgical assessment with sufficient GH decline intraoperatively was likewise judged as complete and was later proved. In three of five patients with inadequate GH decline, endocrinological remission was achieved by performing further surgery. Thus, an endocrinological remission was achieved in 16 of 18 patients (88.9%) with resectable tumors. In 10 patients with nonresectable tumors, the tumor mass was further reduced. Overall, the endocrinological remission rate was 57.1% (16 of 28 patients). There was no serious morbidity and there was no mortality in this series.

We conclude that in patients with transnasally resectable tumor residuals or recurrences confirmed by magnetic resonance imaging, endocrinological remissions can be obtained with high probability, even in secondary surgery after an unsuccessful previous operation.