Table 1 The dosimetric comparison for the VMAT versus the IMPT plans
Organs | Dose levels | Lt. chest wall + regional nodes | Lt. chest wall | Rt. chest wall + regional nodes | Rt. chest wall | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
IMPT | VMAT | P value | IMPT | VMAT | P value | IMPT | VMAT | P value | IMPT | VMAT | P value | ||
PTV | Dmax (GyRBE) | 29.0 ± 1.0 | 28.0 ± 0.8 | < 0.05 | 29.33 ± 1.4 | 28.1 ± 0.8 | < 0.05 | 28.1 ± 0.8 | 27.4 ± 0.7 | 0.1 | 28.3 ± 1.1 | 26.4 ± 3.1 | 0.1 |
D90 (GyRBE) | 25.8 ± 0.3 | 25.6 ± 0.3 | 0.2 | 25.8 ± 0.6 | 25.4 ± 0.3 | < 0.05 | 25.30 ± 0.51 | 25.4 ± 0.2 | 0.4 | 25.4 ± 0.5 | 25.3 ± 0.2 | 0.3 | |
D95 (GyRBE) | 24.8 ± 0.1 | 24.8 ± 0.4 | 0.9 | 24.8 ± 0.2 | 24.7 ± 0.2 | 0.2 | 24.6 ± 0.2 | 24.7 ± 0.3 | 0.4 | 24.8 ± 0.5 | 24.9 ± 0.8 | 0.6 | |
Ipsi-lung | Dmean (GyRBE) | 8.3 ± 1.3 | 7.9 ± 1.7 | 0.4 | 7.4 ± 1.9 | 7.8 ± 0.8 | 0.5 | 7.3 ± 1.2 | 7.9 ± 2.7 | 0.5 | 6.9 ± 1.7 | 8.0 ± 1.2 | 0.1 |
V5 (%) | 55.1 ± 9.2 | 54.6 ± 11.9 | 0.9 | 49.3 ± 10.5 | 54.2 ± 7.0 | < 0.05 | 47.6 ± 8.1 | 57.1 ± 10.9 | < 0.05 | 44.6 ± 10.5 | 52.7 ± 12.1 | 0.1 | |
V10 (%) | 39.3 ± 7.2 | 27.3 ± 8.2 | < 0.05 | 33.3 ± 7.7 | 26.5 ± 4.0 | < 0.05 | 34.8 ± 9.4 | 31.9 ± 4.5 | 0.4 | 29.6 ± 5.4 | 27.9 ± 6.4 | 0.4 | |
V20(%) | 9.7 ± 3.7 | 7.6 ± 4.7 | < 0.05 | 8.5 ± 5.9 | 6.4 ± 3.0 | 0.2 | 9.6 ± 3.4 | 8.2 ± 3.6 | 0.1 | 9.6 ± 4.3 | 8.3 ± 3.9 | 0.3 | |
Contra-lung | Dmean (GyRBE) | 0.2 (0.1–0.3) | 3.4 (2.9–3.7) | < 0.05 | 0.1 (0.1–0.2) | 3.1 (2.7–4.0) | < 0.05 | 0.1 (0.0–0.1) | 3.1 (2.9–3.2) | < 0.05 | 0.0 (0.0–0.1) | 2.6 (2.4–3.0) | < 0.05 |
V5 (%) | 0.6 (0.2–1.2) | 20.9 (14.5–25) | < 0.05 | 0.4 (0–0.9) | 14.1(11.1–26.8) | < 0.05 | 0 (0–0) | 15.8 (12.4–18.7) | < 0.05 | 0 (0–0) | 10.9 (9.4–15) | < 0.05 | |
V10 (%) | 0.1 (0–0.3) | 0.9 (0.6–2.1) | < 0.05 | 0 (0–0) | 0.8 (0.4–1.5) | < 0.05 | 0 (0–0) | 0 (0–0) | < 0.05 | 0 (0–0) | 0.4 (0.2–0.6) | < 0.05 | |
Heart | Dmax (GyRBE) | 16.9 ± 7.0 | 19.9 ± 4.2 | < 0.05 | 16.9 (10.4–25.5) | 18.6 (18.3–22.0) | 0.3 | 10.6 ± 4.8 | 10.1 ± 4.8 | 0.7 | 8.4 (4.8–13.4) | 11.2 (8.4–14.5) | 0.4 |
Dmean (GyRBE) | 1.1 (0.6–2.0) | 4.6 (4.4–4.7) | 0.1 | 1.2(0.7–1.5) | 5 (4.6–5.6) | < 0.05 | 0.4 (0.3–0.7) | 2.8 (2.2–3.4) | < 0.05 | 0.5 (0.2–0.8) | 3.3 (2.5–3.5) | < 0.05 | |
V5 (%) | 7.5 ± 4.0 | 28.2 ± 10.9 | < 0.05 | 8.6 (4.6–10.2) | 33 (26.3–40.2) | < 0.05 | 2.3 (1.6–4.7) | 10.6 (5.4–17.1) | < 0.05 | 2.3 (0.5–5.6) | 16.3 (6–17.8) | < 0.05 | |
V10 (%) | 3.5 (1–6.3) | 8.5 (7.4–11.8) | < 0.05 | 4 (1.1–5.2) | 12 (8.3–14.4) | < 0.05 | 1.2 (0.2–2.2) | 1.7 (0–3) | 0.64 | 0.2 (0–1.2) | 1.1 (0–2.5) | 0.4 | |
V20 (%) | 0.4 (0–0.8) | 0.5 (0.4–1.7) | 0.1 | 0.3 (0–0.6) | 0.5 (0.2–0.6) | 0.2 | 0 (0–0) | 0 (0–0) | 0.6 | 0 (0–0.1) | 0 (0–0) | 0.1 | |
Skin | Dmax (GyRBE) | 28.4 ± 1.2 | 27.3 ± 0.9 | 0.1 | 28.4 ± 1.9 | 27.3 ± 0.8 | < 0.05 | 28.2 ± 1.1 | 26.8 ± 0.6 | < 0.05 | 28.2 ± 1.4 | 26.8 ± 0.6 | < 0.05 |
Dmean (GyRBE) | 24.5 ± 1.1 | 23.4 ± 1.0 | < 0.05 | 24.7 ± 1.7 | 23.2 ± 0.9 | < 0.05 | 25.2 ± 1.7 | 23.3 ± 0.7 | < 0.05 | 24.9 ± 0.8 | 23.3 ± 0.6 | < 0.05 | |
Esophagus | Dmax (GyRBE) | 24.2 ± 2.3 | 22.0 ± 4.2 | < 0.05 | 2.0 (0.6–3.8) | 8.7(8.3–9.6) | < 0.05 | 19.8 ± 4.3 | 19.4 ± 4.3 | 0.7 | 0.2 (0.1–2.4) | 7.9 (5.6–9.8) | < 0.05 |
Dmean (GyRBE) | 4.5 ± 1.7 | 7.0 ± 1.7 | < 0.05 | 0.2 (0.1–0.4) | 3.4 (2.8–3.5) | < 0.05 | 2.9 ± 1.2 | 5. 7 ± 0.9 | < 0.05 | 0 (0–0.2) | 2.9 (2.5–3.0) | < 0.05 | |
Thyroid | Dmax (GyRBE) | 27.7 ± 1.1 | 27.1 ± 1.0 | 0.1 | 1.8(1.2–2.8) | 0.8 (0.7–1) | 0.0 | 26.1 ± 2.0 | 25.2 ± 3.9 | 0.4 | 0.6 (0.0–1.6) | 0.8 (0.7–1.0) | 0.9 |
Dmean (GyRBE) | 13.5 ± 6.0 | 16.3 ± 4.5 | 0.4 | 0.2 (0.1–0.3) | 0.5 (0.4–0.6) | < 0.05 | 12.5 ± 2.7 | 14.8 ± 1.9 | < 0.05 | 0.1 (0–0.3) | 0.5 (0.4–0.6) | < 0.05 | |