Treatment Outcomes and Follow-Up Compliance after Less than Total and Total Resection of Vestibular Schwannomas in 294 Patients

Background: To document the outcomes and quality of follow-up compliance after planned subtotal, near-total and gross-total resection (STR, NTR, and GTR) of vestibular schwannomas (VSs). Methods: This is a retrospective study of 294 consecutive patients, who underwent excision of a previously untreated VS, between 2005 and 2015. Outcomes including long-term tumor control, facial nerve outcomes, and compliance with follow-up advice were studied. Results: The mean diameter of the tumors was 4.2 cm (+/- 0.8 cm; range: 2.2-7.5 cm). Less than total excision was performed in 55 cases (18.7%), of which NTR was performed in 65% of the cases (n = 36) and STR in the remaining 35%. In the GTR group, 29.3% of patients had a good facial outcome (House and Brackmann [HB] grades 1-3) whereas 81.8% of patients undergoing NTR/STR had a good facial outcome. Follow-up was available in 94.5% of patients undergoing NTR/STR whereas only 69.5% of patients undergoing GTR could be followed up. Only 61.8% of the patients who had NTR/STR were compliant with our follow-up advice and were on either regular radiological surveillance or underwent stereotactic radiosurgery (SRS) as advised. In this group of patients, those with larger tumors and those who underwent a more extensive resection of their tumor were less likely to be compliant with follow-up advice (P = 0.043 and 0.007, respectively). Among patients who had GTR, nine patients (3.7%) were detected to have tumor recurrence at a mean interval of 5.5 years after surgery. Conclusion: "Incomplete" microsurgical excision followed by SRS is an effective strategy that fulfills the twin objectives of preservation of function and long-term tumor control. Considering follow-up attrition due to various causes, upfront SRS at the first follow-up visit-even for a small residue-may be a prudent strategy in selected patients.