Prognostic impact of the “Sekhar grading system for cranial Chordomas” in patients treated with pencil beam scanning proton therapy: an institutional analysis

Table 1 Patients’ and disease characteristics (n = 142)

Age at diagnosis	median (range) 42 (1–79)
Gender	n (%)
Female	66 (46)
Male	76 (53)
Histology	n (%)
Non-chondroid	136 (96)
Chondroid	6 (4)
Number of surgeries (biopsies included)	n (%)
1	75 (53)
2	46 (32)
> 2	21 (15)
Maximal extent of resection	n (%)
Gross total resection	19 (13)
Subtotal resection	118 (83)
Biopsy	5 (4)
Surgical complications	n (%)
No	88 (62)
Yes	54 (38)
Brainstem compression before PT	n (%)
No	105 (74)
Abuttment	27 (19)
Yes	10 (7)
Optic pathway compression before PT	n (%)
No	121 (85)
Abuttment	15 (11)
Yes	6 (4)
Any compression/abuttment before PT	n (%)
No	88 (62)
Yes	54 (38)
Delivered dose in GyRBE	median (range)
Total dose	74.0 (72.6–80.0)
Single dose	2.0 (1.8–2.5)
GTV in cc	median (range)
GTV in cc	26.3 (0.0–130.4)
PT for recurrent disease	n (%)
No	120 (85)
Yes	22 (15)

PT proton therapy, GyRBE relative biological effective dose in gray, GTV gross tumor volume, cc cm³

ISSN: 1748-717X