Surgical treatment of acromegaly according to the 2010 remission criteria: systematic review and meta-analysis

In 2010, the Acromegaly Consensus Group revised the criteria for cure of acromegaly and thus rates of surgical remission need to be revised in light of these new thresholds. Two subgroups consisted of patients with discordant GH and IGF-1 levels and patients in remission according to the 2000 criteria, but not to the 2010 criteria, have been reported after adenomectomy and for these subgroups the precise incidence and management has not been established. The objective of the study was to update rates of surgical remission and complications and to evaluate the incidence, management, and long-term outcome of the two previously described subgroups of patients. Systematic review and meta-analysis of surgical series that defined remission according to the 2010 biochemical criteria. We included 13 studies (1105 patients). The pooled rate of overall surgical remission was 54.8 % (95 % CI 44.4-65.2 %), and 72.2 % with previous criteria. Remission was achieved in 77.9 % (95 % CI 68.1-87.6 %) of microadenomas; 52.7 % (95 % CI 41-64.4 %) of macroadenomas; 29 % (95 % CI 20.1-37.8 %) of invasive and 68.8 % (95 % CI 60-77.6 %) of non-invasive adenomas. Complication rates were 1.2 % (95 % CI 0.6-1.9 %) for CSF leak, 1.3 % (95 % CI 0.6-2.1 %) for permanent diabetes insipidus, 8.7 % (95 % CI 4.8-12.5 %) for new anterior pituitary dysfunction and 0.6 % (95 % CI 0.1-1.1 %) for severe intraoperative hemorrhage. We identified an intermediate group of patients, defined as: (1) Remission according to one, but not the other biochemical criteria (GH or IGF-1) or 2010 criteria (14.3 % and 47.1 % cases), (2) Remission according to 2000, but not 2010 criteria (13.2-58.8 % cases). Two studies reported a remission rate of 56.5 % and 100 %, in the two subgroups respectively, in a long-term outcome without adjuvant therapy. Overall remission with transsphenoidal surgery is achieved in similar to 55 % of patients. For the intermediate group of patients, future prospective studies with long-term follow-up are required to determine the long-term biochemical remission rates and clinical implications.