In the past, researchers have focused on destroying cancer. But now that many people survive, or live longer with cancer, some scientists are shifting their focus to medicines that improve the quality of life for patients, says UTMB’s Melinda Sheffield-Moore, a muscle physiologist. "Cancer kills, but cachexia can also kill if you lose a significant amount of muscle," Sheffield-Moore says. Weakened heart muscles might give out, the muscles needed to breathe may not perform adequately or general weakness can make a person susceptible to infections, she says.