Table 2 Risk estimations for radiation-induced mortality.

From: Effects of deep inspiration breath hold on prone photon or proton irradiation of breast and regional lymph nodes

WBI + LNI + MI

Photon

Proton

Ph/Pr DIBH

Ph/Pr SB

DIBH

SB

p-value DIBH-SB

DIBH

SB

p-value DIBH-SB

p-value

p-value

Mean

Range

Mean

Range

Mean

Range

Mean

Range

Heart_mean dose

2.54

(1.43–4.15)

4.55

(2.40–6.58)

 < 0.001

0.78

(0.1–2.11)

1.34

(0.53–2.5)

 < 0.001

 < 0.001

 < 0.001

No cardiac risk factor-no smoking

Risk cardiac death (0.075%/Gy (RBE))

0.19

(0.11–0.31)

0.34

(0.18–0.49)

 

0.06

(0.01–0.16)

0.10

(0.04–0.19)

   

Risk cardiac death (1/N)

525

(932–321)

293

(556–203)

 

1712

(1333–632)

994

(2516–533)

   

Cardiac risk factor(s) or smoking

Risk cardiac death (0.3%/Gy (RBE))

0.76

(0.43–1.25)

1.36

(0.72–1.97)

 

0.23

(0.03–0.63)

0.40

(0.16–0.75)

   

Risk cardiac death (1/N)

131

(233–80)

73

(139–51)

 

428

(3333–158)

249

(629–133)

   

Lungs_mean dose

2.71

(1.72–4.45)

3.08

(2.04–4.89)

 < 0.001

1.78

(1.05–2.80)

1.44

(0.79–2.34)

 < 0.001

 < 0.001

 < 0.001

No smoking

Risk lung cancer death (0.06%/Gy(RBE))

0.16

(0.10–0.27)

0.18

(0.12–0.29)

 

0.11

(0.06–0.17)

0.09

(0.05–0.14)

   

Risk lung cancer death (1/N)

616

(969–375)

542

(817–341)

 

936

(1587–595)

1161

(2110–712)

   

Continuing smoking

Risk lung cancer death (0.88%/Gy(RBE))

2.38

(1.51–3.92)

2.71

(1.80–4.30)

 

1.57

(0.92–2.46)

1.26

(0.70–2.06)

   

Risk lung cancer death (1/N)

42

(66–26)

37

(56–23)

 

64

(108–41)

79

(144–49)

   

Heart disease*lung cancer mortality: 1 − ∏(1 − p) (%)

Low-risk patients (no smoking, no cardiac risk factors) (%)

0.35

(0.21–0.58)

0.52

(0.30–0.79)

 < 0.001

0.17

(0.07–0.33)

0.19

(0.09–0.33)

 < 0.001

 < 0.001

 < 0.001

No smoking, cardiac risk factors (%)

0.92

(0.53–1.51)

1.55

(0.84–2.26)

 < 0.001

0.34

(0.09–0.80)

0.49

(0.21–0.89)

 < 0.001

 < 0.001

 < 0.001

Smoking, no cardiac risk factors (%)

2.57

(1.62–4.22)

3.04

(1.97–4.78)

 < 0.001

1.63

(0.93–2.62)

1.36

(0.73–2.24)

 < 0.001

 < 0.001

 < 0.001

High-risk patients (smoking, cardiac risk factors) (%)

3.12

(1.94–5.11)

4.03

(2.50–6.19)

 < 0.001

1.80

(0.95–3.08)

1.66

(0.85–2.79)

 < 0.001

 < 0.001

 < 0.001

  1. Risk estimations for radiation-induced mortality, based on Taylor et al.7. Over a 30-year period for a 50-year old (reference) patient, the absolute risk of radiation-induced cardiac mortality was estimated 0.075%/Gy and 0.3%/Gy mean heart dose for patients without and with cardiac risk factors, respectively. For radiation-induced lung cancer mortality, the risk was estimated 0.06%/Gy and 0.88%/Gy mean lung dose (both lungs) for patients who never smoked or continued smoking since adolescence, respectively. The rows showing risk cardiac or lung cancer death (1/N) give the values of N where 1 out of N reference patients treated would die from radiation-induced cardiac injury or lung cancer, respectively, during a 30-year follow-up period. The heart disease*lung cancer mortality is the cumulative 30-year risk in (reference) patients who have cardiac risk factors and/or continue smoking. Mortality risks can be compared to the disease-specific survival benefit of adjuvant WBI + LNI including MI, which we assumed to be ≥ 8% at 30 years23. Legend: The columns ‘p-value DIBH-SB’, ‘p-value Ph/Pr DIBH’ and ‘p-value Ph/Pr SB’ represent the p-values of a t-test between the results of a comparison between (respectively): DIBH and SB, photon and proton for DIBH, and photon and proton for SB.