Hyperfractionated high-dose proton beam radiotherapy for clival chordomas after surgical removal

Objective:To evaluate the hyperfractionated high-dose proton beam therapy (PBT) for patients with clival chordomas.Methods:Records for 19 patients with pathologically verified clival chordomas treated with surgery followed by hyperfractionated PBT were retrospectively reviewed. The first 9 consecutive patients were treated with 77.44 cobalt gray equivalents (CGEs) in 64 fractions, and the latter 10 patients were treated with 78.4 CGE in 56 fractions.Results:The median follow-up period of all 19 cases was 61.7 months with a range from 31.5 to 115.4 months. At 5 years, the local control, cause-specific and overall survival rates for all 19 cases were 75%, 94% and 83.2%, respectively. Whereas the 5-year local control, cause-specific and over all survival rates of the latter 10 cases were 100%, 100% and 88.9%, respectively, with a median follow-up period of 59.5 months. One of the first nine patients demonstrated bilateral temporal lobe radiation necrosis, who were successfully treated conservatively. In the ...