Liver cancer rates have more than tripled in the U.S. since 1980 and continue to rise. More than 41,000 people will be diagnosed with liver cancer in the U.S. this year, and about 29,000 will die from the disease, according to the American Cancer Society. Dr. Lionel Kankeu Fonkoua, a Mayo Clinic Comprehensive Cancer Center oncologist, discusses prevention and treatment. Watch: The Mayo Clinic Minute Journalists: Broadcast-quality video pkg (0:59) is in the downloads at…