Proton beam radiation therapy for vestibular schwannomas-tumor control and hearing preservation rates: a systematic review and meta-analysis

Abstract

Objective Proton beam therapy is considered, by some authors, as having the advantage of delivering dose distributions more conformal to target compared with stereotactic radiosurgery (SRS). Here, we performed a systematic review and meta-analysis of proton beam for VSs, evaluating tumor control and cranial nerve preservation rates, particularly with regard to facial and hearing preservation. Methods We reviewed, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) articles published between 1968 and September 30, 2022. We retained 8 studies reporting 587 patients. Results Overall rate of tumor control (both stability and decrease in volume) was 95.4% (range 93.5–97.2%, p heterogeneity= 0.77, p<0.001). Overall rate of tumor progression was 4.6% (range 2.8–6.5%, p heterogeneity < 0.77, p<0.001). Overall rate of trigeminal nerve preservation (absence of numbness) was 95.6% (range 93.5–97.7%, I2 = 11.44%, p heterogeneity= 0.34, p<0.001). Overall rate of facial nerve preservation was 93.7% (range 89.6–97.7%, I2 = 76.27%, p heterogeneity<0.001, p<0.001). Overall rate of hearing preservation was 40.6% (range 29.4–51.8%, I2 = 43.36%, p heterogeneity= 0.1, p<0.001). Conclusion Proton beam therapy for VSs achieves high tumor control rates, as high as 95.4%. Facial rate preservation overall rates are 93%, which is lower compared to the most SRS series. Compared with most currently reported SRS techniques, proton beam radiation therapy for VSs does not offer an advantage for facial and hearing preservation compared to most of the currently reported SRS series.

The Recent Management of Vestibular Schwannoma Radiotherapy: A Narrative Review of the Literature

“…The local control rate was over 95%, and hearing preservation was 43% in the 54 Gy group and 64% in the 50.4 Gy group, with no statistical difference. Finally, in his review, Santacroce et al [ 35 ] described that proton RT did not seem to offer an advantage for facial and hearing preservation compared to most of the currently reported SRS series.…”