Degree of Symptoms May Decide Treatment Approach for Smaller (<2.0cm) Vestibular Schwannoma Tumors

Introduction: Vestibular schwannomas (VS) are common benign tumors. As they grow, they can cause many symptoms, such as hearing loss, tinnitus, or facial nerve weakness. Larger tumors can cause symptoms related to brainstem compression. Treatments for smaller tumors ( < 2.0 cm) include serial MRI observation, stereotactic radiosurgery, or surgical resection, each with varying morbidities. The presence and severity of symptoms may impact the treatment approach, although the final decision is patient driven.

Methods: A single-center retrospective review analyzed patients with VS from 2009 to 2020. The inclusion criteria were patients with a largest tumor dimension < 2.0 cm on radiological imaging without prior treatment. Clinical and operative data were reviewed to assess preoperative symptoms. Multivariate logistic analysis was performed to predict treatment approach, controlling for age, largest tumor dimension, cystic appearance, Koos grade, symptom presence and number.

Results: The study included 273 patients with VS (average age 67.1 ± 14.5 years, 53% female). Presenting symptoms included 12 asymptomatic (4.4%), 226 hearing loss (83.4%), 152 vertigo (55.6%), 96 tinnitus (35.2%), 28 facial paresthesia (10.2%), and 11 facial palsy (4.0%). The average Koos grade was 1.7. For treatment approach, 157 observed with serial MRI (57.5%), 64 underwent surgical resection (23.4%), and 51 received radiosurgery (18.7%). Multivariate linear regression analysis indicated that the largest tumor dimension significantly correlated with vestibular and facial symptoms, and a greater number of symptoms is correlated with higher likelihood of surgical treatment.

Conclusion : The presence of vestibular or facial symptoms themselves did not correlate with accelerated treatment approaches for VS. However, increased number of symptoms was found to be associated with higher chance of undergoing surgical resection. Ultimately, progression of symptom presentation may influence treatment approach the most.