HEALTH NEWS

Study Title:

Silymarin (Milk Thistle) Protects Liver From Chemo

Study Abstract

BACKGROUND:
Despite limited preclinical and clinical investigations, milk thistle (MT) is often used for the treatment of chemotherapy-associated hepatotoxicity. Limited treatment options exist for chemotherapy-related hepatoxicity. Given the wide use of MT, the authors investigated MT in both the laboratory and a clinical setting.

METHODS:
In a double-blind study, children with acute lymphoblastic leukemia (ALL) and hepatic toxicity were randomized to MT or placebo orally for 28 days. Liver function tests were evaluated during the study period. To assess MT in vitro, the authors evaluated supratherapeutic concentrations in an ALL cell line.

RESULTS:
Fifty children were enrolled. No significant differences in frequency of side effects, incidence and severity of toxicities, or infections were observed between groups. There were no significant changes in mean amino alanine transferase (ALT), aspartate amino transferase (AST), or total bilirubin (TB) at Day 28. At Day 56, the MT group had a significantly lower AST (P = .05) and a trend toward a significantly lower ALT (P = .07). Although not significantly different, chemotherapy doses were reduced in 61% of the MT group compared with 72% of the placebo group. In vitro experiments revealed no antagonistic interactions between MT and vincristine or L-asparaginase in CCRF-CEM cells. A modest synergistic effect with vincristine was observed.

CONCLUSIONS:
In children with ALL and liver toxicity, MT was associated with a trend toward significant reductions in liver toxicity. MT did not antagonize the effects of chemotherapy agents used for the treatment of ALL. Future study is needed to determine the most effective dose and duration of MT and its effect on hepatotoxicity and leukemia-free survival.

From press release:

A new study finds that the herb milk thistle may help treat liver inflammation in cancer patients who receive chemotherapy. Published early online in Cancer, a peer-reviewed journal of the American Cancer Society, the study indicates that the herb could allow patients to take potent doses of chemotherapy without damaging their liver.

Chemotherapy drugs frequently cause inflammation in the liver, and when they do, doctors must often lower patients' doses or stop administering the therapies altogether. Clinical studies have investigated using milk thistle to treat liver damage from cirrhosis (from alcohol) or toxins (such as mushroom poisoning). Despite limited study data, the herb is often used for the treatment of chemotherapy associated liver problems. To test whether milk thistle could help treat chemotherapy associated liver problems, Kara Kelly, MD, of the New York-Presbyterian Hospital/Columbia University Medical Center's Herbert Irving Comprehensive Cancer Center in New York City and colleagues conducted a randomized, controlled, double blind study in children with acute lymphoblastic leukemia (ALL), who commonly experience this side effect.

Fifty children with ALL were enrolled in the study and were randomized to receive milk thistle or placebo for 28 days. At the start of the study, all of the children had evidence of liver inflammation as measured by elevations in blood levels of the liver enzymes, aspartate amino transferase (AST) and amino alanine transferase (ALT). When the investigators performed liver function tests on the children at day 56 (28 days after receiving the herb or placebo), children receiving milk thistle had improvements in their liver enzymes compared with children receiving a placebo. Specifically, the group that took milk thistle had significantly lower levels of AST and a trend towards significantly lower levels of ALT. Taking milk thistle also seemed to help keep fewer patients from having to lower the dose of their medications: chemotherapy doses were reduced in 61 percent of the group receiving milk thistle, compared with 72 percent of the placebo group. In addition, milk thistle appeared to be safe for consumption.

The researchers also studied the effects of combining milk thistle with chemotherapy on leukemia cells grown in the laboratory. They found that milk thistle does not interfere with the cancer-fighting properties of chemotherapy.

"Milk thistle needs to be studied further, to see how effective it is for a longer course of treatment, and whether it works well in reducing liver inflammation in other types of cancers and with other types of chemotherapy," said Dr. Kelly. "However, our results are promising as there are no substitute medications for treating liver toxicity."

Study Information

Elena J. Ladas, David J. Kroll, Nicholas H. Oberlies, Bin Cheng, Deborah H. Ndao, Susan R. Rheingold, Kara M. Kelly.
A randomized, controlled, double-blind, pilot study of milk thistle for the treatment of hepatotoxicity in childhood acute lymphoblastic leukemia (ALL)
Cancer
2009 December
Division of Pediatric Oncology, Columbia University Medical Center, New York, New York