Table 4.
DVH parameter comparison
| 60 Gy/5 fr. (60% isodose) | 50 Gy/5 fr. (80% isodose) | Δ (60–50) | P-value | ||
|---|---|---|---|---|---|
| ITV | (ml) | 5.7 (1.0–12.5) | |||
| Mean | (Gy) | 93.5 (89.8–94.6) | 60.3 (58.6–61.1) | 33.09 (30.1–34.7) | <0.01 |
| Minimum | (Gy) | 78.6 (73.2–88.1) | 55.44 (52.4–57.8) | 23.2 (19.5–30.2) | <0.01 |
| Maximum | (Gy) | 100 (100–100) | 62.5 (62.5–62.5) | 37.5 (37.5–37.5) | <0.01 |
| D95 | (Gy) | 85.4 (81.9–89.9) | 57.7 (56.00–59.6) | 27.5 (25.3–31.1) | <0.01 |
| PTV | (ml) | 29.0 (10.1–45.1) | |||
| Mean | (Gy) | 79.3 (74.5–82.1) | 56.4 (54.5–57.5) | 22.7 (20.0–25.8) | <0.01 |
| Minimum | (Gy) | 48.7 (39.2–58.1) | 45.6 (41.5–49.0) | 4.1 (−4.7–9.7) | <0.01 |
| Maximum | (Gy) | 100 (100–100) | 62.5 (62.5–62.5) | 37.5 (37.5–37.5) | <0.01 |
| D95 | (Gy) | 62.2 (60.0–65.8) | 50.9 (50.090–51.7) | 11.3 (8.4–15.0) | <0.01 |
| Total lung | (ml) | 3086 (2127–3997) | |||
| Lung—ITV | (ml) | 3080 (2121–3991) | |||
| Mean lung dose | (Gy) | 3.2 (1.5–6.3) | 3.0 (1.4–5.7) | 0.2 (−0.3–0.6) | <0.01 |
| V5 | (%) | 12.2 (4.4–26.6) | 12.7 (4.7–26. 7) | −0.1 (−2.2–1.2) | 0.65 |
| V10 | (%) | 8.0 (3.0–16.8) | 8.2 (2.7–17.0) | 0.3 (−1.2–3.1) | 0.23 |
| V15 | (%) | 5.8 (2.4–12.1) | 5.5 (2.2–12.1) | −0.1 (−0.8–0.9) | 0.66 |
| V20 | (%) | 4.3 (1.7–9.3) | 4.0 (1.5–8.7) | 0.1 (−0.6–0.8) | 0.26 |
| Chest wall | |||||
| V30 | (ml) | 29.1 (4.6–51.5) | 16.7 (4.00–42.7) | 6.4 (−0.7–19.5) | <0.01 |
| V40 | (ml) | 9.7 (0.7–23.1) | 5.2 (0.3–25.5) | 3.7 (−3.8–7.4) | <0.01 |
DVH = dose–volume histogram, fr. = fractions, Δ (60–50) = each gap value between regimens of 60 Gy/5 fr.(60% isodose) and 50 Gy/5 fr.(80% isodose), P-value = probability value, ITV = internal target volume, D95 = more than 95% of the planning target volume, PTV = planning target volume, Vn = normal lung volume receiving ≥ n Gy.