How does laughter treat cancer?

Some people think the camaraderie fostered by laughter banishes fear and promotes relaxation, which helps the healing process. Some cancer-treatment centers prescribe "laughter therapy" into patients' treatment plans. Pediatric hospitals use clown therapy to help children tolerate the anxiety, nausea and pain associated with radiation treatment and chemotherapy. Statistics show more than 100 hospitals in the U.S. have either humor rooms filled with toys, games, books and comedy movies or comedy carts filled with games and toys for bedside visits.