Table 4.

Summary of main published studies on particle therapy for grade 2 and grade 3 meningiomas

Authors	Patients (grade, no)	Treatment modality	Median dose GyE	Median Follow-up (months)	Progression-free survival, %	Overall survival,%	Toxicity
Slater et al 2012 [79]	G2, 4 G1, 47	Proton	59	74	G2,50 at 5 years GI, 99 at 5 years	NA	6 patients developed neurologic symptoms
Adeberg et al 2012 [1]	G2, 62 G1, 23	FSRT, IMRT, Carbon Ion	57.6	73	G2, 95 and 50, G3, 63 and 13, at 2 and 5 years	81 (G2) and 53 (G3) at 5 years	NA
Combs et al. 2013 [18]	G2/3, 36	Photon RT and a carbon ion boost	Photon RT, 50; carbon ion boost, 18	12	54 and 33 at 1 and 2 years	NA	No grade 3/4 toxicity
Combs et al. 2013 [19]	G2, 23 G3, 4	Carbon ion	Photon RT 50; carbon ion boost, 18	6	81 at 12 months	NA	No grade 3/4 toxicity
Murray et al. 2017 [61]	G2, 33 G3, 2	Proton	62.0	56.9	68 at 5 years	80.7 at 5 years	Optic tract and pituitary toxicities, fatigue impaired hearing
El Shafie et al. 2018 [24]	G2, 25 G3, 6	Proton and carbon ion boost	Photon, 54; carbon ion boost, 18	49.7	71 and 56.5 at 1 and 2 years	89.6 at 1year 71.4 at 2 years	No grade IV or V toxicities

RT, radiation therapy; IMRT, intensity-modulated radiation therapy; FSRT, fractionated stereotactic radiotherapy; NA, not assessed