Surgical salvage of recurrent vestibular schwannoma following prior stereotactic radiosurgery

Objectives/Hypothesis To evaluate outcomes of salvage surgery for vestibular schwannoma (VS) that failed primary stereotactic radiosurgery (SRS). Methods Case‐control study of 37 patients who underwent surgical resection of sporadic VS following prior SRS at two tertiary academic referral centers between 2003 and 2015. A cohort of nonirradiated control subjects, matched according to tumor size, age, and treatment center, were used as comparison. Results Thirty‐seven patients were included. The median time from radiation to surgical salvage was 36 months (range 9.6–153 months). Following tumor progression after SRS, 18 (49%) patients underwent gross total resection, 10 (27%) underwent near‐total resection, and nine (24%) underwent subtotal resection. Postoperative complications following salvage surgery included one (3%) case of stroke, four (11%) cases of cerebrospinal fluid leak, and two (5%) cases of meningitis. Twenty‐seven (73%) patients had good postoperative facial nerve outcome (House‐Brackmann Score I–II) at long‐term follow‐up. There were no cases of tumor recurrence or regrowth after a median length of 26 months following microsurgical salvage (range 3–114 months). The rate of satisfactory postoperative facial nerve function was not different between study and control subjects (73% vs. 76%; P = 0.8); however, less‐than‐complete resection was utilized more frequently among previously radiated patients (P = 0.01). Conclusion Microsurgical salvage of VS following primary radiation therapy is challenging. Less‐than‐complete resection is required in a greater percentage of patients to preserve facial nerve integrity and prevent neurological complications. Long‐term follow‐up is needed to determine the risk of delayed progression following incomplete tumor removal. Level of Evidence 3b. Laryngoscope, 126:2580–2586, 2016