Sayde Patel believes she is lucky to be living at a time when so many clinical trials are available to help women and men with metastatic (stage IV) cancers. And it's also good for her dog, Stella. The better Sayde feels, the more likely her four-legged companion will get a daily walk from her favorite master.

Any treatment that uses elements of the body’s immune system to fight cancer is considered cancer immunotherapy. In recent years, as research has revealed many of the basic workings of the immune system and how the immune system interacts with tumor cells, scientists have developed, tested, and demonstrated the effectiveness of an array of immunotherapy techniques. Several have shown immense promise in various types of cancer.