If you continue to smoke, then live with no regrets if you develop a horrible disease

I quit smoking because I had cancer at a young age and knew I was at high risk for a reocurrence for the rest of my life. If the cancer ever came back, I didn't want to wonder if it was caused by my smoking. I know the answer to that question now, since in August, I was diagnosed with cancer again. While I don't know why it reoccurred, I know it wasn't from smoking. Some may ask if I don't