Introduction: Pituitary tumors have historically challenged neurosurgeons and otolaryngologists. The endoscopic endonasal transsphenoidal approach (EEA) has emerged as the most widely used technique to resect pituitary tumors, primarily because it offers improved visualization and reduces post-operative complications. Despite its prevalence, long-term studies (greater than four years) on pituitary tumor recurrence rates (RR) and complications have not been conducted. Present literature is largely limited to two years of follow-up due to logistical constraints of follow-up on patients that may not be symptomatic.

Methods: This study analyzed patient data from pituitary tumor resections that were done by a single neurosurgeon using EEA. With this criteria, 25 patients were found to have greater than four years of consistent follow-up. The following factors were analyzed: tumor size, region, and pathology; intraoperative cerebrospinal fluid (CSF) leak; tumor RR. Questionable tumor recurrences were reviewed and confirmed by board certified neuroradiologists using MRIs.

Results: 12% of patients were found to have a tumor recurrence in comparison to the 34.1% long-term tumor RR cited in literature for transsphenoidal hypophysectomy(X2(1)=4.08,p<0.05). Two out of the three patients with tumor recurrence took 72 and 55 months, respectively, to show evidence on MRI. 4% of patients had evidence of a CSF leak compared to 2.7% CSF leak rate for transsphenoidal hypophysectomy(X2(1)=0.128,p>0.05).

Conclusions: EEA is the viable approach in limiting long-term tumor recurrence over transsphenoidal hypophysectomy. Constant vigilance is also important, as there was evidence of tumor recurrence after four years of follow up. Furthermore, the lack of statistically significant difference between the two surgical approaches over CSF leak showcases the potential of EEA because with this approach neurosurgeons are more likely to resect tumors that are not accessible by transsphenoidal hypophysectomy, and therefore theoretically there is increased risk of diaphragma sellae herniation. This lack of difference proves that neurosurgeons are not endangering patients with EEA.

Patient Care: This research improves patient care because it showcases the importance of long-term follow up when analyzing pituitary tumor recurrence. Despite the wide acceptance of EEA as the go-to surgical approach for pituitary tumor resection, long-term studies have not been conducted. Until studies like this one have been completed, concrete conclusions cannot be drawn that EEA is clearly the superior surgical approach over transspheonidal hypophysectomy.

Learning Objectives: By the conclusion of this session, participants should be able to understand the importance of EEA in resecting pituitary tumors. They will appreciate the knowledge gap that is being filled in regard to long-term follow up, as current follow-up is largely limited to two years. Participants will also be able to discuss methods in encouraging more patients that undergo EEA for their tumor resections to continue follow-up even after four years have transpired post-surgically.

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