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24 May 2012

Answer to Question #882 Submitted to "Ask the Experts"

Category: Radiation Effects — Cancer and Leukemia Risks

The following question was answered by an expert in the appropriate field:

Is the cancer risk associated with low-level radiation exposure different for a person with precancerous lesions such as those found in the esophagus from Barrett's metaplasia?

Esophageal cancer has been called an excellent model of multifactorial action in which, despite continuing ambiguity of some of the components, one can discern the pattern of multistage carcinogenesis. The role of gastric reflux postulated by Barrett in the metaplastic change you identified fits this concept. Since ionizing radiation can produce initiation or progression of the process, one would expect a stochasticly increased probability of the occurence of the cancer associated with "low level" radiation exposure based on classic assumptions. In reality, I know of no human evidence to validate the theoretical model for a radiation-related increase in esophageal cancer at such levels. Niel Wald, M.D.

Answer posted on 25 May 2001. The information and material posted on this website is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Website. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.