There are some cancers that can possibly be cured by embolisms. As strange as it may sound, it's true. When a cancer spreads, like into the lungs, sometimes the cancerous parts can be set inside a bubble, basically, and transported away so that an injection can be made of an oxygen blocking agent that will encounter the cancer and deprive it of what it needs in order to survive.
The most common cancer this treatment may be effective on is colorectal cancer. When all of the cancer except for a tiny bit that has spread is able to be removed in surgery, this technique can sometimes kill the cancer that spread. Other times this treatment is useful is when a cancer comes back after it has been cured once. It's truly amazing all the advancements that have taken place as progress is being made to totally cure cancer all together.