What are the major causes of cancer? 

Cancer is a type of chronic disease that persists due to many factors. It may happen as a result of genetic mutation, obesity, lifestyle, exposure to radiation. For the proper diagnostics one must consult a cancer doctor. Some of the major causes of can be:

Genetics.

Viruses and other infections.

Excess sun exposure & radiation.

Excessive use of smoke and tobacco use.

Lack of physical activity.