Executive summary

This systematic review and meta-analysis included 14 primary studies comprising 1,145 patients (671 treated with PBT and 474 with CIRT). The only difference between the two groups showed at 3-year that PBT seemed better in local control (90% vs. 83%; p = 0.05) and progression-free survival (94% for PBT vs. 83% for CIRT; p = 0.09). However, there was no significant difference between PBT and CIRT in LC at 5-year (76% vs 74%), at 7-year (71% vs 74%).

There was no significant difference in the pooled OS rates which were at both 3-year and 5 -year PBT 83% vs CIRT 89%, and at 7-year PBT 82% vs CIRT 88%. There was no significant difference in progression-free survival at 5-year PBT 84% vs CIRT 81%. No occurrences of higher-grade acute toxicities were reported. Late toxicities were more severe, including cases of optic neuropathy, brain necrosis, and hearing loss.

Grade 3 and 4 toxicities were more frequently associated with CIRT, particularly radiation necrosis. The conclusion of this review is that both PBT and CIRT are effective treatments for skull base chordoma, with comparable long-term efficacy.