Biochemical Remission in Acromegaly Following Endoscopic Endonasal Resection: Safety and Outcomes of the 15-Year, 103-Patient Experience with Medial Cavernous Wall Resection

Introduction: Report on the long-term remission rates of a large number of acromegaly patients and analyze the safety and efficacy of the medial wall resection (MWR) technique refined at our institution and performed with increasing frequency during the period studied.

Methods: A total of 104 patients with acromegaly received 106 surgeries via the EEA between 2007-2022 and were included. Patient demographics, clinical presentations, tumor radiographic and pathological characteristics were collected. The definition of biochemical remission as specified by the 2010 Acromegaly consensus criteria was employed.

Results: The median follow-up time was 4.6 years (interquartile range, IQR: 1.2-8.0), and median volume was 1.10 (IQR 0.39-3.33). Fifty-seven percent of tumors were Knosp 0, while the remainder were Knosp 1 (17%), 2 (12%), 3 (10%), and 4 (4%). MWR was performed in 59 of 106 cases, and there was only one case of carotid artery injury early in the experience. MWR was otherwise not associated with greater rates of intra-operative or post-operative CSF leak, operative hematoma or epistaxis, or permanent cranial nerve palsies. The 1-, 3-, and 5-year biochemical remission rates after surgery alone were 87%, 80%, and 78%, respectively. This improved to 98%, 96%, and 94% with use of rescue medications at the time of relapse. In univariate Cox modeling for factors associated with biochemical relapse, gross total resection (HR = 0.28, p = 0.005), immediate post-operative remission (GH < 1.15 within 48 hours) (HR = 0.09, p = 0.002), lower peak pre-operative Insulin Growth Factor-1 (IGF-1) levels (HR = 0.09, p = 0.004) were associated with decreased relapse. On multivariable analysis, only immediate remission (HR = 0.23, p = 0.013) and lower peak IGF-1 (HR = 1.002, p = 0.012) were associated with long-term biochemical remission.

Conclusion : Acromegaly is a life-threatening disease that can be adequately managed with EEA with or without adjuvant therapy, and MWR is a highly safe technique in experienced hands that yielded significantly greater remission rates in our series. MWR may be indicated in more cases than currently used.