Table 6.

Relationship between colon radiation dose and risk of second primary solid cancer among survivors of various types of cancer within the LSS cohort

Colon dose (Gy)No. of second primary casesRR* (95% CI)
Stomach cancer survivors
    <0.0051011.00 (reference)
    0.005–0.49930.78 (0.58–1.04)
    0.50–0.9980.80 (0.39–1.65)
    1.00–1.9981.28 (0.62–2.64)
    ≥2.0062.34 (1.02–5.39)
ERR/Gy*0.39 (−0.01 to 0.96)
Colon cancer survivors
    <0.005391.00 (reference)
    0.005–0.49511.23 (0.79–1.91)
    0.50–0.9951.31 (0.51–3.38)
    1.00–1.9941.52 (0.53–4.30)
    ≥2.0011.16 (0.16–8.55)
ERR/Gy*0.27 (NE–1.27)
Thyroid cancer survivors
    <0.005151.00 (reference)
    0.005–0.49190.80 (0.40–1.59)
    0.50–0.9992.05 (0.87–4.87)
    1.00–1.9973.36 (1.32–8.57)
    ≥2.0052.79 (0.99–7.85)
ERR/Gy*1.24 (0.27–3.10)
Lung cancer survivors
    <0.005151.00 (reference)
    0.005–0.49241.38 (0.69–2.75)
    0.50–0.9910.33 (0.04–2.62)
    1.00–1.9931.95 (0.55–6.96)
    ≥2.0013.42 (0.43–27.04)
ERR/Gy*0.12 (NE–1.36)
Female breast cancer survivors
    <0.005351.00 (reference)
    0.005–0.49591.30 (0.85–1.99)
    0.50–0.9991.12 (0.54–2.34)
    1.00–1.99102.45 (1.21–4.95)
    ≥2.00114.17 (2.08–8.35)
ERR/Gy*1.05 (0.42–2.01)
Thyroid cancer survivors
    <0.005171.00 (reference)
    0.005–0.49240.87 (0.46–1.63)
    0.50–0.9931.24 (0.36–4.29)
    1.00–1.9953.80 (1.34–10.75)
    ≥2.0033.40 (0.97–11.93)
ERR/Gy*1.25 (0.21–3.26)
  • *RR and ERR/Gy are adjusted for sex, city, attained age, age at time of bombing, and age at first cancer diagnosis (second primary cancer risk estimates only).

  • P < 0.05.

  • The lower bound of the confidence interval could not be estimated (NE) by the statistical model.