Outcomes of Redo Endoscopic Endonasal Skull Base Surgery for Recurrent or Residual Nonfunctioning Pituitary Adenomas: An Analysis of 93 Consecutive Patients at the University of Pittsburgh Medical Center

Background: Pituitary adenomas account for ~10 to 20% of all intracranial tumors, and nonfunctional adenomas (NFA) are the second most common subtype. NFA recurrence is common, particularly following incomplete resection, and has been reported as 12 to 58% within 5 years. The endoscopic endonasal approach (EEA) has become the mainstay of treatment for symptomatic NFAs, but there is a paucity of data describing the unique challenges and documenting the clinical outcomes and recurrence of NFAs following redo EEA after prior transsphenoidal surgery.

Methods: Ninety-three consecutive patients with recurrent or residual NFAs that were resected via EEA at the University of Pittsburgh Medical Center between 2007 and 2020 were included and described in [Table 1]. Operative reports were analyzed for challenges relating to prior surgery, including difficulty with dissection, landmark identification, or otherwise distorted anatomy. Cases were monitored for comprehensive neurological, endocrinologic, ophthalmologic, and otolaryngologic outcomes following surgery. Progression-free survival (PFS) after surgery with and without adjuvant radiation was measured using Kaplan–Meir methods.

Results: Thirty five percent of surgeries were noted to be challenging due to prior surgery ([Table 2]). Challenges were associated with longer surgery (4.5 hours in challenging versus 3.5 hours in non-challenging cases, p = 0.040), but not with gross total resection (GTR) rates (OR = 1.28, p = 0.588), or postoperative hospitalization length (median 3 days, p = 0.558). GTR was achieved in 39% of cases, and the median K_i-67 score was 2% (interquartile range, IQR: 1–3%). There were no carotid injuries in the series. In patients with preoperative visual deficit, there were documented improvements in vision in 64% of cases. Six of 9 patients with preoperative ophthalmoplegia improved ([Fig. 1A]). Eight patients were taken back to the operating room for cerebrospinal fluid leak repair, and 2 were taken back for hematoma evacuation. Six patients (7%) suffered from olfactory change persisting beyond 6 months ([Fig. 1B]). The median duration of post-operative radiographic follow-up was 53 months (IQR: 15–91). The 5-year PFS was 73% and improved with GTR (86% for GTR versus 65% for subtotal resection, p = 0.035) but was not associated with Knosp score (p = 0.675). Eighteen of 57 patients who underwent non-GTR received adjuvant radiotherapy, with a 5-year PFS of 68 versus 56% (p = 0.0504) for those receiving subtotal resection alone ([Fig. 2]).

Discussion and Conclusion: Redo EEA for NFA is safe and effective. Challenges due to difficult anatomy from prior transsphenoidal approach may add time to the case, but are not associated with decreased GTR rates.

Publication History

Article published online:
01 February 2023