Question: Is it true that some cancers are caused by bad luck in cell division?

Samantha Terry answered on 12 Mar 2015:

In some ways yes. But bad cell division is not usually a bad luck situation. If cells divide wrongly and have the wrong number of chromosomes in a cell, then unless the cells already had something wrong with them to get past the cell cycle checkpoints, they would die and thus not pass on the anomaly to the daughter cells. Cancer go wrong more when the DNA gets damaged and this is not picked up by the many proteins that are involved in repairing this damage. You can often get translocations where one part of the chromosome swaps with a different part. this is often undetected by the repair proteins and will thus carry on. if the new chromosomes with the parts swapped happen to encode more ‘cancer’ proteins then you have a higher risk of getting cancer.
The damage you get in the first place is part genetics (so bad luck, but you couldn’t do anything about it) and part environment, some of which you also can’t do anything about, but others you can like wearing sun cream and not smoke.