Introduction
Patients and methods
Patients
Carbon-ion radiotherapy
Clinical and dosimetric analysis
Evaluation of radiation pneumonitis
Follow-up
Statistical analysis
Results
Patient characteristics
Factors | Number (%) |
---|---|
Age (years) | |
median (range) | 74 (46–88) |
Sex | |
Male | 51 (78) |
Female | 14 (22) |
PS | |
0 | 22 (34) |
1 | 39 (60) |
2 | 4 (6) |
Location of primary tumor | |
Right upper lobe | 23 (35) |
Right middle lobe | 4 (6) |
Right lower lobe | 17 (26) |
Left upper lobe | 16 (25) |
Left lower lobe | 5 (8) |
Clinical Stage | |
II A | 8 (12) |
II B | 29 (45) |
III A | 16 (25) |
III B | 12 (18) |
Histology | |
Squamous cell carcinoma | 35 (54) |
Adenocarcinoma | 26 (40) |
Large cell carcinoma | 2 (3) |
Non small-cell carcinoma | 2 (3) |
Total dose | |
68 Gy (RBE)/16 fr | 9 (14) |
72 Gy (RBE)/16 fr | 45 (69) |
76 Gy (RBE)/16 fr | 11 (17) |
Chemotherapy | |
Yes | 14 (22) |
No | 51 (78) |
Smoking status | |
Current or previous | 56 (86) |
Never | 9 (14) |
Pulmonary emphysema | |
Yes | 12 (18) |
No | 53 (82) |
Incidence of radiation pneumonitis (RP)
G0 | G1 | G2 | G3 | G4 and G5 | |
---|---|---|---|---|---|
Number of patients | 32 | 24 | 6 | 3 | 0 |
Clinical factors associated with ≥ grade 2 RP
Parameters | No of patients with ≥ G2 RP (%) | No of patients with G0-1 RP (%) |
p value |
---|---|---|---|
Age | 0.074 | ||
< 75 years old | 1 (11) | 25 (45) | |
≥ 75 | 8 (89) | 31 (55) | |
Sex | 0.392 | ||
Man | 6 (67) | 45 (80) | |
Female | 3 (33) | 11 (20) | |
PS | 0.458 | ||
0 or 1 | 8 (89) | 53 (95) | |
2 | 1 (11) | 3 (5) | |
Location of primary tumor | 0.706 | ||
Upper or Middle lobe | 7 (78) | 36 (64) | |
Lower lobe | 2 (22) | 20 (36) | |
Clinical Stage | 1.000 | ||
II | 5 (56) | 32 (57) | |
III | 4 (44) | 24 (43) | |
Total dose | 1.000 | ||
≤ 72 Gy RBE | 8 (89) | 46 (82) | |
> 72 Gy RBE | 1 (11) | 10 (18) | |
Chemotherapy | 0.187 | ||
Yes | 0 | 14 (25) | |
No | 9 (100) | 42 (75) | |
Brinkman Index | 1.000 | ||
< 600 | 3 (33) | 19 (34) | |
≥ 600 | 6 (67) | 37 (66) | |
Pulmonary emphysema | 0.191 | ||
Yes | 0 | 12 (21) | |
No | 9 (100) | 44 (79) |
Parameters | ≥grade 2 (min - max) | grade 0–1 (min - max) |
p value |
---|---|---|---|
%VC (%) | 67.5 (37.1–86.9) | 89.2 (53.2–120.8) | 0.002 |
FEV1 (L) | 1.17 (0.5–1.78) | 1.67 (0.6–3.33) | 0.043 |
FEV1/FVC (%) | 70.0 (56.2–83.7) | 65.6 (34.2–99.7) | 0.556 |
%DLCO (%) | 72.6 (32.8–123.9) | 78.0 (29.5–178.4) | 0.644 |
Dose-volume analysis of ≥ grade 2 RP
Parameters | ≥ grade 2 (min - max) | grade 0–1 (min - max) |
p value |
---|---|---|---|
PTV (cm3) | 448.5 (155.8–712.7) | 371.0 (73.8–1319.8) | 0.193 |
MLD (Gy RBE) | 12.0 (6.5–17.0) | 9.0 (2.9–16.2) | 0.023 |
V5 (%) | 33.8 (17.9–49.0) | 24.9 (7.0–46.1) | 0.034 |
V10 (%) | 30.6 (15.3–46.2) | 22.6 (6.5–42.6) | 0.045 |
V20 (%) | 24.5 (10.1–31.4) | 17.9 (5.6–36.7) | 0.039 |
V30 (%) | 19.0 (10.1–31.4) | 12.9 (3.7–23.6) | 0.015 |
V40 (%) | 12.2 (5.2–18.1) | 8.8 (3.1–18.9) | 0.052 |
V50 (%) | 6.7 (2.6–13.3) | 5.8 (2.1–14.2) | 0.442 |
Multivariate analysis of risk factors for ≥ grade 2 RP
≥grade 2 Radiation Pneumonitis | ||
---|---|---|
Factor | Odds Ratio (95% CI) |
p value |
%VC (<86.9% vs ≥86.9%) | 13.7 (2.09–276.2) | 0.0041 |
V30 (≥15% vs <15%) | 6.1 (1.29–36.3) | 0.0221 |