Majority of cancer types due to "bad luck"
Far more types of cancer are due to "bad luck"--random stem cell mutations--than are caused by genetic or environmental factors, according to a study by researchers at the Johns Hopkins Kimmel Cancer Center.
The scientists, who published their report in the journal Science, used scientific literature to analyze 31 types of cancer. They evaluated the stem cell divisions in each type of cancer and compared these rates with the lifetime risk of developing these cancers. And they concluded that random DNA mutations during cell division may account for 65 percent of cancer types compared to 35 percent due to hereditary or environmental factors.
More specifically, the researchers say that cell mutations primarily accounted for 22 of the 31 types of cancer that were analyzed, including ovarian, pancreatic, bone and testicular cancer. Not surprisingly, environmental factors played a more significant role in certain cancers, such as lung cancer, tied to smoking, and skin cancer, linked to sun exposure.
The report also noted that while the majority of cancers are primarily caused by cell mutations, following a poor lifestyle can increase the chances of those mutations occurring.