gms | German Medical Science

Objective: Acromegaly is associated with increased morbidity and mortality. Surgery as first-line therapy is the only therapeutic option which can achieve immediate GH regression. Thus the detection of postoperative residual disease should be defined early to optimize following management strategies. We are the first to present results of the first day postoperative follow-up for basal fasting GH and suppression with oral glucose.

Method: Patients were sampled for GH and IGF-1 on POD 1. Remission was defined as basal GH < 1ng/ml and nadir GH < 0,4ng/ml. IGF-1 is not expected to be normal on POD 1 and thus not included in our early remission criteria. Early second look surgery was performed within 7 days if biochemical control could not be defined. We reviewed histopathological findings to determine remained GH- secreting adenoma tissues. Again basal and nadir GH levels were checked on the 1^st day after revision. We then evaluated our total remission rate.

Results: 36 patients with GH secreting adenomas unterwent transsphenoidal surgery between 2007–2014 by a single neurosurgeon. 25/36 patients (69,4%) were found to be in remission after surgery according to basal GH and nadir GH level on POD 1. In 3 cases suppression test with orale glucose was repeated due to paradoxic increase of GH. 6 patients underwent an early second look operation. The intraoperative inspection revealed tumor suspected tissue which could be confirmed as GH secreting adenoma on immunohistochemical investigation in 3/6 cases. Remission could be achieved for 4/6 patients after revision. In 2 of these 4 cases remission was proved although adenoma could not be identified histologically. In total, biochemical control could be achieved in 29/36 cases (80,6%). Patients who could not be defined as cured on POD 1 were not in remission in 3-month postoperative follow-up.

Conclusions: In our series we could achieve a high remission rate of 80,6% when taking remission after early second look surgery into account. Performing GH assay on POD 1 is not common. But an early detection of residual or persistent GH excess after surgery is essential to benefit the management strategies such as early revision surgery which contributes to a higher remission score. In this respect further investigations addressing early identification of residual disease are required.