Lance Armstrong got his wins taken away from him because he used performance enhancing drugs. Why are performance enhancing drugs banned? Because they can be harmful to the users.
The guy overcame cancer. How bad can the performance enhancing drugs be? For all we know, if he took them, they helped him overcome the cancer.
On the other hand, I know there are bodybuilders that die in their 40s most likely because of the same performance enhancing drugs.