How related are Cancer and Mutations?

The article "Study: DNA Errors Responsible for Most Cancer Mutations" discusses a study that examined mutations across 32 types of cancers. Most people know to avoid certain environmental factors such as smoking. On the other hand, most people do not know that in time a normal cell divides and copies its DNA to produce new cells, which can cause multiple mistakes. These mistakes may be the cause to why certain cancers are more common than others. The analysis showed that 66% of mutations contribute to cancer that's due to unavoidable DNA-replication mistakes, while 29% are due to environmental factors and only 5% to heredity. However, only 3 or 4 more mutations can cause a cell to turn completely malignant. This means that 2/3 of cancers are not caused by random copying errors nor does it say that random errors cause most of the mutations of all cancers. The researchers did find a correlation with cancer incidence and normal cell divisions between 17 cancer types. Since the researchers found this connections between cell division and cancer, is the next step devising a way to limit these mutations from happening? I like when more research is being done on cancer since it is just a diverse disease. 

Cancer Types
DNA Mutations