<abstract xmlns="http://www.w3.org/1999/xhtml"><sec id="j_raon-2017-0044_s_007_w2aab3b7b8b1b6b1aab1c18b1Aa"><h3>Background</h3><p>Although the effects of high dose radiation on human cells and tissues are relatively well defined, there is no consensus regarding the effects of low and very low radiation doses on the organism. Ionizing radiation has been shown to induce gene mutations and chromosome aberrations which are known to be involved in the process of carcinogenesis. The induction of secondary cancers is a challenging long-term side effect in oncologic patients treated with radiation. Medical sources of radiation like intensity modulated radiotherapy used in cancer treatment and computed tomography used in diagnostics, deliver very low doses of radiation to large volumes of healthy tissue, which might contribute to increased cancer rates in long surviving patients and in the general population. Research shows that because of the phenomena characteristic for low dose radiation the risk of cancer induction from exposure of healthy tissues to low dose radiation can be greater than the risk calculated from linear no-threshold model. Epidemiological data collected from radiation workers and atomic bomb survivors confirms that exposure to low dose radiation can contribute to increased cancer risk and also that the risk might correlate with the age at exposure.</p></sec><sec id="j_raon-2017-0044_s_008_w2aab3b7b8b1b6b1aab1c18b2Aa"><h3>Conclusions</h3><p>Understanding the molecular mechanisms of response to low dose radiation is crucial for the proper evaluation of risks and benefits that stem from these exposures and should be considered in the radiotherapy treatment planning and in determining the allowed occupational exposures.</p></sec></abstract>

BackgroundAlthough the effects of high dose radiation on human cells and tissues are relatively well defined, there is no consensus regarding the effects of low and very low radiation doses on the organism. Ionizing radiation has been shown to induce gene mutations and chromosome aberrations which are known to be involved in the process of carcinogenesis. The induction of secondary cancers is a challenging long-term side effect in oncologic patients treated with radiation. Medical sources of radiation like intensity modulated radiotherapy used in cancer treatment and computed tomography used in diagnostics, deliver very low doses of radiation to large volumes of healthy tissue, which might contribute to increased cancer rates in long surviving patients and in the general population. Research shows that because of the phenomena characteristic for low dose radiation the risk of cancer induction from exposure of healthy tissues to low dose radiation can be greater than the risk calculated from linear no-threshold model. Epidemiological data collected from radiation workers and atomic bomb survivors confirms that exposure to low dose radiation can contribute to increased cancer risk and also that the risk might correlate with the age at exposure.ConclusionsUnderstanding the molecular mechanisms of response to low dose radiation is crucial for the proper evaluation of risks and benefits that stem from these exposures and should be considered in the radiotherapy treatment planning and in determining the allowed occupational exposures.

Carcinogenesis induced by low-dose radiation

Department of Medical Physics, Greater Poland Cancer Centre

Radiology and Oncology

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

{"article-title":"Carcinogenesis induced by low-dose radiation"}

BackgroundAlthough the effects of high dose radiation on human cells and tissues are relatively well defined, there is no consensus regarding the effects of...

	Dose range	Examples of exposure
Very low doses	< 0.05 Gy	Mammography4, chest X-ray4
Low doses	0.05–0.5 Gy	Cardaic CT angiogram4
Medium doses	0.5–5 Gy	One fraction dose in standard fractionated radiotherapy5, dose absorbed by workers during Fukushima accident6
High doses	5–15 Gy	Intraoperative radiotherapy (as boost)7
Very high doses	> 15 Gy	Intraoperative radiotherapy8, cumulative dose delivered during fractionated radiotherapy5

Carcinogenesis induced by low-dose radiation

Article Category: Review

Publié en ligne: 01 nov. 2017

Pages: 369 - 377

Reçu: 04 juil. 2017

Accepté: 25 sept. 2017

DOI: https://doi.org/10.1515/raon-2017-0044

© 2017 Igor Piotrowski, Katarzyna Kulcenty, Wiktoria Maria Suchorska, Agnieszka Skrobała, Małgorzata Skórska, Marta Kruszyna-Mochalska, Anna Kowalik, Weronika Jackowiak, Julian Malicki

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Figure 1

Figure 2

Dose ranges and sources of radiation exposure