Most cancers are caused by bad luck not genes or lifestyle, say scientists

No because we can't control cell reproduction to any significant degree compared to what happens automatically. If you're careful not to cut your skin and cause extra cell reproducing as it heals, you're still shedding your entire skin surface every few days due to natural growth and death anyway.

Seems like it: https://news.ycombinator.com/item?id=8829913

From what I can tell, they were counting incidence, and relating it to the rate of cell division of that particular tissue. This strong correlation allowed them to rule out outside influence (not just lifestyle, also genetics and other environmental factors) as being statistically significant to the incidence of those cancers. Only a couple cancers (the article specifically notes lung cancer and certain skin cancers), had statistically significant deviations from what the rate of division would suggest.

The chart at the top is a bit disingenuous - you can't really say that those cancers are "caused" by outside influences, but it does indicate that they actually play a role in a statistically significant number of cases, as opposed to the other cancers, which are due largely to random chance (if the study's results are correct). There are probably still a large number of lung cancer cases, for example, caused by bad luck.

Regardless of the conclusions regarding the environmentally influenced cancers, the impact on our understanding of other cancers, which include very common and deadly ones such as pancreatic and colon cancer, is still immense and important.

Disclaimer: IANA doctor or statistician