This phase I trial studies the side effects and best dose of defined green tea catechin
extract and to see how well it works in preventing liver cancer in participants with
cirrhosis. Higher levels of the molecule gamma-OHPdG may be found in participants with
cirrhosis, which may mean a higher risk of the development of liver cancer. Defined green tea
catechin extract may work better to lower levels of gamma-OHPdG and prevent the development
of liver cancer.