Incidence of Breast Cancer in the Life Span Study of Atomic Bomb Survivors: 1958–2009

Journal Article · Wed Jul 25 00:00:00 EDT 2018 · Radiation Research

DOI:https://doi.org/10.1667/rr15015.1· OSTI ID:1613769

Brenner, Alina V. ^[1]; Preston, Dale L. ^[2]; Sakata, Ritsu ^[3]; Sugiyama, Hiromi ^[3]; de Gonzalez, Amy Berrington ^[4]; French, Benjamin ^[3]; Utada, Mai ^[3]; Cahoon, Elizabeth K. ^[4]; Sadakane, Atsuko ^[3]; Ozasa, Kotaro ^[3]; Grant, Eric J. ^[3]; Mabuchi, Kiyohiko ^[4]

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1. Radiation Effects Research Foundation, Hiroshima and Nagasaki (Japan); DOE/OSTI
2. Hirosoft International, Eureka, CA (United States)
3. Radiation Effects Research Foundation, Hiroshima and Nagasaki (Japan)
4. National Inst. of Health (NIH), Bethesda, MD (United States)

The importance of reproductive history in breast tissue development and etiology of sporadic breast cancer in females is well established. However, there is limited evidence of factors, other than age, that modify risk of radiation-related breast cancer. In this study, we evaluated breast cancer incidence in the Life Span Study cohort of atomic bomb survivors, adding 11 years of follow-up and incorporating reproductive history data. We used Poisson regression models to describe radiation risks and modifying effects of age and reproductive factors. Among 62,534 females, we identified 1,470 breast cancers between 1958 and 2009. Of 397 new cases diagnosed since 1998, 75% were exposed before age 20. We found a strong linear dose response with excess relative risk (ERR) of 1.12 per Gy [95% confidence interval (CI): 0.73 to 1.59] for females at age 70 after exposure at age 30. The ERR decreased with increasing attained age (P = 0.007) while excess absolute rate (EAR) increased with attained age up to age 70 (P < 0.001). Age at menarche was a strong modifier of the radiation effect: for a given dose, both the ERR and EAR decreased with increasing age at menarche (P = 0.007 and P < 0.001). Also, independently, age-at-exposure effects on ERR and EAR differed before and after menarche (P = 0.043 and P = 0.015, respectively, relative to log-linear trends), with highest risks for exposures around menarche. Despite the small number of male breast cancers (n = 10), the data continue to suggest a dose response (ERR per Gy = 5.7; 95% CI: 0.3 to 30.8; P = 0.018). Persistently increased risk of female breast cancer after radiation exposure and its modification pattern suggests heightened breast sensitivity during puberty.

• Research Organization: National Academy of Sciences, Washington, DC (United States)
• Sponsoring Organization: USDOE Office of Environment, Health, Safety and Security (AU)
• Grant/Contract Number: HS0000031
• OSTI ID: 1613769
• Journal Information: Radiation Research, Journal Name: Radiation Research Journal Issue: 4 Vol. 190; ISSN 0033-7587
• Publisher: Radiation Research Society
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
Biophysics
Life Sciences &amp; Biomedicine - Other Topics
Radiology
Nuclear Medicine &amp; Medical Imaging