Open AccessProgressive Vestibular Schwannoma following Subtotal or Near-Total Resection: Dose-Escalated versus Standard-Dose Salvage Stereotactic Radiosurgery
Author(s) -
Mohamed H. Khattab,
Alexander D. Sherry,
Nauman F. Manzoor,
Douglas J. Totten,
Guangcheng Luo,
Lola B. Chambless,
Alejandro Rivas,
David S. Haynes,
Anthony J. Cmelak,
Albert Attia
Publication year - 2020
Publication title -
journal of neurological surgery. part b, skull base
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.488
H-Index - 42
eISSN - 2193-6331
pISSN - 2193-634X
DOI - 10.1055/s-0040-1712462
Subject(s) - medicine , radiosurgery , cohort , surgery , retrospective cohort study , schwannoma , nuclear medicine , radiology , radiation therapy
Objective Local failure of incompletely resected vestibular schwannoma (VS) following salvage stereotactic radiosurgery (SRS) using standard doses of 12 to 13 Gy is common. We hypothesized that dose-escalated SRS, corrected for biologically effective dose, would have superior local control of high-grade VS progressing after subtotal or near-total resection compared with standard-dose SRS. Design Retrospective cohort study. Setting Tertiary academic referral center. Participants Adult patients treated with linear accelerator-based SRS for progressive VS following subtotal or near-total resection. Main Outcome Measures Dose-escalated SRS was defined by a biologically effective dose exceeding a single-fraction 13-Gy regimen. Study outcomes were local control and neurologic sequelae of SRS. Binary logistic regression was used to evaluate predictors of study outcomes. Results A total of 18 patients with progressive disease following subtotal (71%) and near-total (39%) resection of Koos grade IV disease (94%) were enrolled. Of the 18 patients, 7 were treated with dose-escalated SRS and 11 with standard-dose SRS. Over a median follow-up of 32 months after SRS, local control was 100% in the dose-escalated cohort and 91% in the standard-dose cohort ( p = 0.95). Neurologic sequelae occurred in 28% of patients, including 60% of dose-escalated cohort and 40% of the standard-dose cohort ( p = 0.12), although permanent neurologic sequelae were low at 6%. Conclusions Dose-escalated SRS has similar local control of recurrent VS following progression after subtotal or near-total resection and does not appear to have higher neurologic sequalae. Larger studies are needed.