30 years follow-up and increased risks of breast cancer and leukaemia after long-term low-dose-rate radiation exposure

Br J Cancer. 2017 Dec 5;117(12):1883-1887. doi: 10.1038/bjc.2017.350. Epub 2017 Oct 3.

Abstract

Background: The current study followed-up site-specific cancer risks in an unique cohort with 30 years' follow-up after long-term low-dose-rate radiation exposure in Taiwan.

Methods: Six thousand two hundred and forty two Taiwanese people received extra exposure in residential and school buildings constructed with Co-60-contaminated steel from 1982 until informed and relocated in early 1990s. The additional doses received have been estimated. During 1983-2012, 300 cancer cases were identified through the national cancer registry in Taiwan, 247 cases with minimum latent periods from initial exposure. The hazard ratios (HR) of site-specific cancers were estimated with additional cumulative exposure estimated individually.

Results: Dose-dependent risks were statistically significantly increased for leukaemia excluding chronic lymphocytic leukaemia (HR100mSv 1.18; 90% CI 1.04-1.28), breast cancers (HR100mSv 1.11; 90% CI 1.05-1.20), and all cancers (HR100mSv 1.05; 90% CI 1.0-1.08, P=0.04). Women with an initial age of exposure lower than 20 were shown with dose response increase in breast cancers risks (HR100mSv 1.38; 90% CI 1.14-1.60; P=0.0008).

Conclusions: Radiation exposure before age 20 was associated with a significantly increased risk of breast cancer at much lower radiation exposure than observed previously.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Breast Neoplasms / epidemiology*
  • Child
  • Child, Preschool
  • Cobalt Radioisotopes / adverse effects*
  • Construction Materials / adverse effects*
  • Dose-Response Relationship, Radiation
  • Environmental Exposure / adverse effects*
  • Female
  • Follow-Up Studies
  • Humans
  • Infant
  • Infant, Newborn
  • Leukemia / epidemiology*
  • Male
  • Middle Aged
  • Radiation Exposure / adverse effects*
  • Risk Factors
  • Sex Factors
  • Taiwan / epidemiology
  • Time Factors
  • Young Adult

Substances

  • Cobalt Radioisotopes