Endoscopic Endonasal Pituitary Surgery For Nonfunctioning Pituitary Adenomas: Long-Term Outcomes and Management of Recurrent Tumors

Introduction Endoscopic endonasal approaches (EEAs) provide improved access and operative visualization for resection of pituitary adenomas. Although the technique has gained wide acceptance, there is a paucity of data regarding late recurrence. Objective We aim to assess long-term outcomes of patients with nonfunctioning pituitary adenomas (NFPAs) who underwent EEA. Methods We reviewed 269 patients operated on for an NFPA between 2005 and 2015. Clinical and radiologic factors including those potentially related to higher chances of recurrence were analyzed. Progression-free survival was analyzed using the Kaplan-Meier method, and univariate and multivariate survival were analyzed using a Cox regression model. Results The study included 269 patients. The gross total resection rate was 46.0% (n = 124) but cavernous sinus involvement was present in almost half the patients (n = 115). The probability of recurrence at 5 years and 10 years was 22.0% and 47.2%, respectively. The median time to recurrence was 10 years for patients without cavernous sinus involvement and 6 years for those with cavernous sinus involvement. Univariate and multivariate analysis showed that tumor size, cavernous sinus invasion, anterior skull base extensions, and residual tumor were significantly associated with recurrence. Conclusions Recurrence rate of NFPA remains high despite the better visualization offered by EEA, especially in those tumors involving the cavernous sinus and/or previously operated on. Repeat surgery is adequate for tumor debulking and decompression of the optic apparatus but is unlikely to achieve gross total resection if a successful previous EEA has been performed. Radiation therapy is an effective option for management of recurrent tumors.