Second cancers per kg of tissue was lower in volumes exposed to low-dose radiation when compared to volumes with no radiation exposure, in radiation therapy patients

[XLNT Foundation]

Tubiana et al. studied a French-United Kingdom cohort of 5,000 survivors of a childhood cancer cohort treated in eight centers in France and the UK before 1985 and followed for an average of 29 years (Tubiana et al., 2011). Second cancers per kg of tissue were determined and plotted as a function of the average radiation dose to the tissue during radiation therapy (see graph below).

Reduction of second cancers per kg of tissue was observed in regions of the body subjected to radiation dose of ~20 cGy during radiation therapy, in comparison to regions not subjected to any radiation dose.

These data indicate that low radiation doses reduce the cancer risk consistent with radiation hormesis and contradicting the LNT model.

References

TUBIANA, M. et al. A new method of assessing the dose-carcinogenic effect relationship in patients exposed to ionizing radiation. A concise presentation of preliminary data. Health Phys, v. 100, n. 3, p. 296-9, Mar 2011. https://www.ncbi.nlm.nih.gov/pubmed/21595074