Sex and age associations with vestibular schwannoma size and presenting symptoms

OBJECTIVE: To assess the association of sex and age with presenting symptoms and size of vestibular schwannoma at clinical presentation to our clinics. STUDY DESIGN: Retrospective chart review. SETTING: Academic medical center. PATIENTS: Approximately 1,269 subjects diagnosed with unilateral vestibular schwannoma between 1997 and 2010. INTERVENTION: Demographic information, tumor characteristics, and treatment strategy were recorded. MAIN OUTCOME MEASURE: Tumor size, patient-reported presence of hearing loss or dizziness at presentation. RESULTS: Male subjects had significantly larger tumors than female subjects at presentation (18.23 versus 16.81 mm, p = 0.031); this difference was particularly pronounced in patients younger than 40 years. Patient-reported symptoms at baseline also differed by sex: the prevalence of hearing loss was 95.1% in male subjects versus 90.3% in female subjects (p = 0.001), and the frequency of dizziness was 74.3% in female subjects versus 59.0% in male subjects (p<0.0001). In multivariate analyses, male subjects continued to have a borderline significant positive association with tumor size (p = 0.066) and were 2-fold more likely to have hearing loss (odds ratio [OR], 2.082; 95% confidence interval [CI], 1.300-3.336) but half as likely to have dizziness (OR, 0.501; 95% CI, 0.387-0.649) than female subjects. Additionally, for every 1-mm increase in tumor size, patients were more likely to report hearing loss by 14.7% (OR, 1.147; 95% CI, 1.106-1.191) and dizziness by 2.8% (OR, 1.028; 95% CI, 1.016-1.041). CONCLUSION: We observed significant sex differences in the presentation and size of unilateral vestibular schwannomas. As management and treatment strategies are predicated on presenting symptoms and patient factors, these observations merit further study to further understand tumor biology, improve risk stratification, and optimize tumor management.