My mother is Schitzophrenic and may have cancer....?

okay so my mother is 40 years old and I do not really see her often she was diagnosed with schitzophrenia about 27 years ago but has never been compliant with meds and has been doing cocaine and has done heroin and many other drugs since she was 13. She is going tomorrow for a colonoscopy as the doctor thinks she may have cancer (her blood tests keep showing up as abnormal) I was just wondering what are the effects of being schitzo, doing drugs and having cancer have on the body