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Object: With limited studies available, the correlation between the extent of resection and tumor recurrence in vestibular schwannomas (VSs) has not been definitively established. In this prospective study, the authors evaluated 772 patients who underwent microsurgical resection of VSs to analyze the association between total tumor resection and the tumor recurrence rate., Methods: The authors selected all cases from a prospectively collected database of patients who underwent microsurgical resection as their initial treatment for a histopathologically confirmed VS. Recurrence-free survival was analyzed using Kaplan-Meier analysis. The authors studied the impact of possible confounders such as patient age and tumor size using stepwise Cox regression to calculate the proportional hazard ratio of recurrence while controlling for other cofounding variables., Results: The authors analyzed data obtained in 571, 89, and 112 patients in whom gross-total, near-total, and subtotal resections, respectively, were performed. A gross-total resection was achieved in 74% of the patients, and the overall recurrence rate in these patients 8.8%. There was no significant relation between the extent of resection and the rate of tumor recurrence (p = 0.58). As expected, the extent of resection was highly correlated with patient age, tumor size, and surgical approach (p < 0.0001). Using Cox regression, the authors found that the approach used did not significantly affect tumor control when the extent of resection was controlled for., Conclusions: While complete tumor removal is ideal, the results presented here suggest that there is no significant relationship between the extent of resection and tumor recurrence.

Background: Cystic vestibular schwannomas (VSs) are described as being more aggressive than solid tumors., Objective: We examined 468 VS patients to evaluate whether the presence of cystic components in VSs may be an important feature for predicting postoperative outcome., Methods: We selected all VS patients from a prospectively collected database (1984-2009) who underwent microsurgical resection for VS. Hearing data were analyzed using American Association of Otolaryngology-Head and Neck Surgery. Facial nerve dysfunction was analyzed using the House-Brackmann scale. We used univariate comparisons to determine the clinical impact of cystic changes on preoperative and postsurgical hearing and facial nerve preservation., Results: We identified 58 patients (11%) with cystic changes and 410 patients with solid VSs. In this analysis, cystic VS patients tended to have larger tumors (78% of patients with >2.0 cm extrameatal extension) compared with the solid VS group, which consisted of many smaller and medium-sized tumors (P < .0001). Univariate analyses found that tumors with cystic changes did not lead to worse rates of preoperative hearing loss (χ(2), P = not significant) compared with solid VSs. Cystic changes conferred worse postoperative hearing in patients with medium-sized tumors (P = .035). Cystic changes also did not significantly affect facial nerve outcomes (χ(2), P = not significant)., Conclusion: Cystic tumors tend to be larger than noncystic tumors and affect outcomes by reducing the rate at which hearing preservation is attempted and by worsening hearing outcome in medium-sized tumors. Further, peripheral cysts cause lower rates of hearing preservation compared with centrally located cysts.

Avoidance of facial nerve palsy is one of the major goals of vestibular schwannoma (VS) microsurgery. In this study, we examined the significance of previously implicated prognostic factors (age, tumor size, the extent of resection and the surgical approach) on post-operative facial nerve function. We selected all VS patients from prospectively collected database (1984-2009) who underwent microsurgical resection as their initial treatment for histopathologically confirmed VS. The effect of variables such as surgical approach, tumor size, patient age and extent of resection on rates facial nerve dysfunction after surgery, were analyzed using multivariate logistic regression. Patients with preoperative facial nerve dysfunction (House-Brackman [HB] score 3 or higher) were excluded, and HB grade of 1 or 2 at the last follow-up visit was defined as "facial nerve preservation." A total of 624 VS patients were included in this study. Multivariate logistic regression analysis found that only pre-operative tumor size significantly predicted poorer facial nerve outcome for patients followed-up for ≥6 and ≥12 months (OR 1.27, 95% CI 1.09-1.49, p < 0.01; OR 1.35, 95% CI 1.10-1.67, P < 0.01, respectively). We found no significant relationship between facial nerve function and age, extent of resection, surgical approach, or tumor size (when extent of resection and surgical approach were included in the regression analysis). Because facial nerve palsy is a debilitating and psychologically devastating condition for the patient, we suggest altering surgical aggressiveness in patients with unfavorable tumor anatomy, particularly in cases with large tumors where overaggressive resection might subject the patient to unwarranted risk. Residual disease can be followed and controlled with radiosurgery if interval growth is noted.

Background: There are few published prospective data sets specifically focusing on patients younger than 40 years old undergoing microsurgery for vestibular schwannoma., Objective: We describe functional outcomes and long-term tumor control after surgery in patients younger than 40 years old enrolled in a prospectively collected database over a 25-year period., Methods: We selected all vestibular schwannoma patients from a prospectively collected database who were younger than 40 years old at the time of surgical resection for a vestibular schwannoma. Rates of tumor control and hearing preservation were analyzed using Kaplan-Meier analysis, and risk factors for facial nerve palsy, hearing loss, and trigeminal neuropathy were analyzed using multivariate logistic regression., Results: A total of 204 patients younger than 40 years of age met our inclusion criteria and were included in the analysis. Our data indicate that surgical resection leads to durable long-term freedom from tumor recurrence or progression in 89% of young patients at 15 years of follow-up. Consistent with other published series, hearing was preserved in 68% of patients with smaller tumors (<3 cm). Facial nerve function was preserved in 76% of patients with smaller tumors and 52% of patients with larger tumors (P<.001). On multivariate logistic regression, tumor size was a significant predictor of hearing loss, whereas gross total resection was nearly a significant predictor of hearing loss controlling for other variables (P=.06)., Conclusion: We present the largest prospectively studied cohort of young patients undergoing microsurgical resection of vestibular schwannoma. These data suggest that surgical resection provides excellent long-term tumor control in these patients.

The prognostic significance of intraoperative facial nerve electromyography (EMG) changes is not well-established in vestibular schwannoma (VS) surgery. We studied facial nerve EMG with a threshold >0.05mA and performed subgroup analyses based on tumor size, resection approach, and extent of resection, for prediction of long-term facial nerve outcome. A total of 477 surgically treated VS patients were included. Elevated stimulation threshold exceeding >0.05mA is a highly specific (90%), but very insensitive (29%) finding in this cohort. The positive predictive value and negative predictive values (NPV) of facial nerve EMG for detection of permanent facial palsy are 68% and 63%, respectively. The NPV decreased with increasing tumor size (72% versus [vs.] 64% vs. 53%) due to the increasing prevalence of post-operative facial nerve palsy in these patients. In conclusion, while facial nerve EMG is a critical adjunct for locating the facial nerve intraoperatively, its predictive value for facial nerve function remains to be determined.