Multimodality Treatment of Large Vestibular Schwannomas

Vestibular schwannomas are WHO grade I tumors of the eighth cranial nerve that lead to hearing loss, tinnitus, vestibular dysfunction, and facial nerve compromise. The management of vestibular schwannomas consists of observation, radiosurgery, or microsurgical resection. In this review, we discuss the various treatment modalities specifically targeting large vestibular schwannomas in addition to their treatment risk profiles. Although there has been a trend towards treatment with radiosurgery for smaller lesions, consensus reports still advocate for surgical debulking in patients with large vestibular schwannomas. There has been a shift in management philosophy towards functional preservation at the cost of more extensive resection, yet subtotal resection of vestibular schwannomas is associated with higher rates of recurrence on follow-up. Some groups have demonstrated new promise for the management of large vestibular schwannomas with stereotactic radiosurgery alone and multimodality therapy involving subtotal surgical resection with planned postoperative radiosurgery to residual tumor. Although most groups would still advocate for microsurgical debulking of large vestibular schwannomas with evidence of brainstem compression, hybrid treatment strategies have become preferable. More work is required to determine which patients are at risk of progression after a subtotal resection to stratify those who should or should not receive postoperative stereotactic radiosurgery.