My mother passed away from stomach cancer at 65. She was neither overweight, nor drank a drop of alcohol. She never ever smoked in her life. My father-in law was a smoker, drank alcohol regularly, ate rich food consisting of meat and sugar and he died of other complications at 75. These may be risk factors for half of the cancer numbers. The other half must be genetic mutation. Either way, it’s one of the scariest diseases.