Reseachers from John Hopkins Cancer created a statistical model measuring the proportion of cancer incidence caused by random mutations during stem cell division; this was published in the journal, Science in January of 2015. They concluded that 2/3 of cancers can be explained by "bad luck." What they really determined was an association rather than a proven cause.

Events seem random when we don't understand why they happen. Perhaps these seemingly random events are not mistakes at all; they may be events caused by mechanisms that are unknown. How do we explain the increase in the frequency of cancers when comparing to 100 years ago when cancer was a relatively rare disease?