Fig. 2

The case report of a 61 year-old male patient of the study, with an inoperable 8-cm sacrococcygeal chordoma treated by helical tomotherapy at a dose of 70 Gy. Treatment tolerance was excellent, with no acute or late toxicities and good efficacy on pain management. We note a regression of the tumor seen in MRI evaluations before helical tomotherapy (top line), at 1.5 years (middle line) and at 3 years (bottom line), in all directions mainly in the anterior-posterior plane from 83 mm to 38 mm (left: T2 sequences; right: axial T1 sequences after Gadolinium injection)