RT Journal
A1 Samartzis, Dino
A1 Nishi, Nobuo
A1 Cologne, John
A1 Funamoto, Sachiyo
A1 Hayashi, Mikiko
A1 Kodama, Kazunori
A1 Miles, Edward F.
A1 Suyama, Akihiko
A1 Soda, Midori
A1 Kasagi, Fumiyoshi
T1 Ionizing Radiation Exposure and the Development of Soft-Tissue Sarcomas in Atomic-Bomb Survivors
JF The Journal of Bone & Joint Surgery
JO The Journal of Bone & Joint Surgery
YR 2013
FD February 6
VO 95
IS 3
SP 222
OP 229
DO 10.2106/JBJS.L.00546
UL http://dx.doi.org/10.2106/JBJS.L.00546
AB Background: 
  Very high levels of ionizing radiation exposure have been associated with the development of soft-tissue sarcoma. The effects of lower levels of ionizing radiation on sarcoma development are unknown. This study addressed the role of low to moderately high levels of ionizing radiation exposure in the development of soft-tissue sarcoma.Methods: 
  Based on the Life Span Study cohort of Japanese atomic-bomb survivors, 80,180 individuals were prospectively assessed for the development of primary soft-tissue sarcoma. Colon dose in gray (Gy), the excess relative risk, and the excess absolute rate per Gy absorbed ionizing radiation dose were assessed. Subject demographic, age-specific, and survival parameters were evaluated.Results: 
  One hundred and four soft-tissue sarcomas were identified (mean colon dose = 0.18 Gy), associated with a 39% five-year survival rate. Mean ages at the time of the bombings and sarcoma diagnosis were 26.8 and 63.6 years, respectively. A linear dose-response model with an excess relative risk of 1.01 per Gy (95% confidence interval [CI]: 0.13 to 2.46; p = 0.019) and an excess absolute risk per Gy of 4.3 per 100,000 persons per year (95% CI: 1.1 to 8.9; p = 0.001) were noted in the development of soft-tissue sarcoma.Conclusions: 
  This is one of the largest and longest studies (fifty-six years from the time of exposure to the time of follow-up) to assess ionizing radiation effects on the development of soft-tissue sarcoma. This is the first study to suggest that lower levels of ionizing radiation may be associated with the development of soft-tissue sarcoma, with exposure of 1 Gy doubling the risk of soft-tissue sarcoma development (linear dose-response). The five-year survival rate of patients with soft-tissue sarcoma in this population was much lower than that reported elsewhere.Level of Evidence: 
  Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.