Skip to main content

Table 4 Comparison of absolute dose between gating and ITV-based plans to (a) Spinal Cord, (b) Heart, (c) Ribs, (d) Esophagus, (e) Bronchial Tree, and (f) Trachea for each fractionation scheme. Clinical endpoints are listed for each organ as well as dose limits taken from RTOG 0915 and TG101 for 4 × 12 Gy and 3 × 18 Gy fractionation regimens, respectively

From: To gate or not to gate - dosimetric evaluation comparing Gated vs. ITV-based methodologies in stereotactic ablative body radiotherapy (SABR) treatment of lung cancer

(a) Dmax to Volume = 0.35 cc (Gy) Dmax (Gy)
Spinal Cord: Myelitis Limit Gating ITV Difference Limit Gating ITV Difference
4 × 12 Gy 20.8 9.03 ± 4.27 (2.2, 20.9) 9.30 ± 4.36 (1.9, 21.3) 0.49 ± 2.28 (−7.7, 10.5) 26 10.60 ± 4.93 (2.4, 25.1) 10.84 ± 5.00 (2.1, 25.7) 0.48 ± 2.79 (−10.1, 11.5)
3 × 18 Gy 18 9.88 ± 4.71 (2.3, 22.4) 10.28 ± 4.74 (1.8, 23.1) 0.55 ± 2.69 (−8.6, 10.4) 21.9 11.63 ± 5.49 (2.6, 28.0) 12.08 ± 5.44 (2.2, 26.5) 0.64 ± 3.24 (−11.4,10.9)
(b) Dmax to Volume = 15 cc (Gy) Dmax (Gy)
Heart: Pericarditis Limit Gating ITV Difference Limit Gating ITV Difference
4 × 12 Gy 28 8.49 ± 8.08 (0.2, 35.8) 8.83 ± 4.40 (0.2, 31.7) 0.46 ± 2.11 (−7.7, 6.2) 34 15.93 ± 14.86 (0.2, 55.2) 16.06 ± 13.55 (0.2, 52.4) 0.37 ± 4.00 (−15.9, 12.7)
3 × 18 Gy 24 9.39 ± 8.80 (0.2, 36.2) 9.69 ± 8.01 (0.2, 35.4) 0.29 ± 2.59 (−10.4, 7.1) 30 17.95 ± 16.39 (0.2, 62.3) 17.81 ± 14.86 (0.2, 57.6) −0.14 ± 5.13 (−16.8, 14.2)
(c) Dmax to Volume = 1 cc (Gy) Dmax (Gy)
Ribs: Fracture Limit Gating ITV Difference Limit Gating ITV Difference
4 × 12 Gy 32 42.12 ± 9.97 (19.3, 55.1) 42.26 ± 9.70 (20.5, 57.0) 0.14 ± 4.19 (−7.3, 17.2) 40 49.83 ± 6.96 (21.3, 59.0) 49.38 ± 3.79 (26.4, 58.7) −0.45 ± 3.12 (−11.0, 7.5)
3 × 18 Gy 28.8 47.80 ± 11.45 (21.4, 61.8) 46.65 ± 10.75 (23.1, 64.1) −1.15 ± 4.88 (−11.1, 15.4) 36.9 55.98 ± 8.72 (23.6, 66.8) 54.97 ± 7.71 (29.9, 66.1) −1.01 ± 3.61 (−10.8, 10.4)
(d) Dmax to Volume = 5 cc (Gy) Dmax (Gy)
Esophagus: Stenosis Limit Gating ITV Difference Limit Gating ITV Difference
4 × 12 Gy 18.8 5.91 ± 4.83 (0.3, 21.5) 6.45 ± 4.68 (0.4, 17.8) 0.54 ± 1.95 (−6.3, 8.4) 30 11.96 ± 9.36 (0.6, 48.1) 12.48 ± 7.99 (0.6, 35.3) 0.53 ± 3.97 (−14.6, 16.3)
3 × 18 Gy 17.7 6.59 ± 5.35 (0.4, 24.2) 7.08 ± 5.10 (0.4, 19.8) 0.49 ± 2.26 (−7.6, 9.1) 25.2 13.55 ± 10.32 (0.7, 52.8) 13.85 ± 8.42 (0.7, 35.7) 0.30 ± 4.53 (−17.3, 13.8)
(e) Dmax to Volume = 4 cc (Gy) Dmax (Gy)
Bronchial Tree: Stenosis Limit Gating ITV Difference Limit Gating ITV Difference
4 × 12 Gy 15.6 9.52 ± 9.46 (0.8, 34.8) 8.54 ± 7.30 (0.8, 24.3) −0.99 ± 2.97 (−10.5, 1.5) 34.8 25.95 ± 16.63 (8.5, 54.4) 24.37 ± 13.92 (10.0, 52.0) −1.58 ± 4.65 (−14.4, 2.4)
3 × 18 Gy 15 11.02 ± 10.86 (0.9, 38.6) 9.19 ± 7.53 (0.9, 25.4) −1.83 ± 3.98 (−13.2, 1.9) 30 29.08 ± 18.76 (8.3, 58.7) 26.39 ± 15.23 (10.9, 58.5) −2.69 ± 6.09 (−16.8, 3.9)
(f) Dmax to Volume = 4 cc (Gy) Dmax (Gy)
Trachea: Stenosis Limit Gating ITV Difference Limit Gating ITV Difference
4 × 12 Gy 15.6 1.07 ± 1.79 (0.1, 4.3) 1.29 ± 1.89 (0.1, 4.6) 0.22 ± 0.31 (0.0, 0.7) 34.8 2.47 ± 2.96 (0.1, 6.20) 2.73 ± 2.89 (0.1, 6.3) 0.26 ± 0.44 (0.0, 1.0)
3 × 18 Gy 15 1.27 ± 2.16 (0.1, 5.1) 1.50 ± 2.27 (0.1, 5.5) 0.24 ± 0.33 (0.0, 0.7) 30 3.01 ± 3.72 (0.1, 8.1) 3.28 ± 3.66 (0.1, 8.3) 0.28 ± 0.45 (0.0, 1.1)