Milk thistle has been used for thousands of years as a liver tonic. Researches from Columbia University Medical Center reported in the journal Cancer, that milk thistle may also protect the liver during chemotherapy treatment. The researchers suggest that the antioxidant silybin may be the key ingredient of milk thistle.
Liver toxicity is a common side effect of chemotherapy for acute lymphoblastic leukemia (ALL) which is a blood cancer. When the liver becomes more toxic, the doctor must choose between cutting back on treatment which may allow the cancer to continue to grow, or going ahead with the full treatment and taking a chance on possible liver damage. The use of milk thistle could change this Russian roulette.
"Study participants were assigned to take either a milk thistle pill or a placebo capsule for one month. At the start of the study, all 50 children were suffering from liver inflammation due to prior rounds of chemotherapy. By the end, children taking milk thistle had significantly lower levels of two liver inflammation markers than children taking a placebo."
http://www.naturalnews.com/028652_chemotherapy_milk_thistle.html