Cancer Risk and the Environment

The development of cancer is heavily influenced by external factors, a recent study finds.About a year ago, a study published in the journal Science received a lot of attention and comment because it seemed to suggest that most cancers were mainly the result of random mutations or “bad luck.”  I wrote about the study, including what commenters identified as some of its major weaknesses, in a post last January on Cancer Risk and “Bad Luck.”

A new study by a different team, published recently in Nature, revisits the question. It expands on the analysis in last year’s study and examines the question using several different approaches. It arrives at the conclusions that the development of cancer is heavily influenced by external factors. Continue reading

Camp Lejeune, Environmental Toxins And Breast Cancer Risk

What are the links between environmental toxins and breast cancer risk?It’s recognized that environmental factors play a role in the development of many types of cancer, including breast cancer.  But, unfortunately, there are more questions than there are answers right now about the extent of that role. Studies so far have not been able to clarify how and to what extent exposures to harmful substances in the environment increase our risk for breast cancer.

An opportunity to gain some insight on this issue could potentially come from a study now underway of male breast cancer and exposure to contaminated drinking water at Camp Lejeune in North Carolina.  Results from the study are expected some time this year.

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Cancer Risk and “Bad Luck”

How much cancer risk is related mostly to random genetic mutations?Are a large proportion of cancer cases mainly the result of “bad luck”? That is certainly the impression given by recent media reports about a study conducted by researchers at Johns Hopkins University and published in the journal Science.

What did the researchers do and what did this study actually show? Is it really time to reconsider our understanding of cancer and its causes? Continue reading