Breast Cancer ChoicesTM
|Scrutinizing the evidence for breast
cancer procedures and treatments
|Should I take vitamins during cancer treatments?
The subject has actually been studied.
Please show your doctors.
Antioxidants May Aid Chemotherapy Patients: Study
FOR IMMEDIATE RELEASE
EVANSTON, IL (April 24, 2007) — There is no evidence that antioxidant supplements
interfere with the therapeutic effects of chemotherapy agents, according to a recent
systematic review of the use of antioxidants during chemotherapy, available in the May,
2007 issue of the peer-reviewed journal Cancer Treatment Reviews. In fact, they may
help increase survival rates, tumor response, and the patient’s ability to tolerate
treatment. This conclusion has important implications for patients whose oncologists
discourage the use of antioxidant supplements during treatment. Until now, their
concern has been that these supplements may counteract the tumor-shrinking abilities
of the chemotherapy.
“This review demonstrates that there is no scientific support for the blanket objection
to using antioxidants during chemotherapy. In addition, it also appears that these
supplements may help mitigate the side effects of chemotherapy,” said Keith I. Block,
MD, lead author of the study and Medical Director of the Block Center for Integrative
Cancer Treatment. “This is significant because it increases the likelihood that patients
will be able to complete their treatment.”
Co-author Dr. Robert Newman, Professor of Cancer Medicine at M. D. Anderson
Cancer Center said, “This study, along with the evolving understanding of antioxidant-
chemotherapy interactions, suggests that the previously held beliefs about
interference do not pertain to clinical treatment.”
The analysis, titled “Impact of Antioxidant Supplementation on Chemotherapeutic
Efficacy: A Systematic Review of the Evidence from Randomized Controlled Trials,”
evaluated 845 articles from five scientific databases that examined the effects of
taking natural antioxidant supplements concurrent with chemotherapy.
Out of the 845 studies that were analyzed, 19 met all evaluation criteria. These
included the use of randomized trials with a control group, and the reporting of
treatment response (tumor shrinkage) and survival data. The 1,554 patients
represented had a variety of cancer types, and most had advanced or relapsed
disease. Some of the antioxidants used in the trials included glutathione, vitamin A,
vitamin C, vitamin E, ellagic acid, selenium and beta carotene.
Among the findings:
• All of the studies that included survival data showed similar or better survival rates
for the antioxidant group than the control group.
• None of the trials supported the theory that antioxidant supplements diminish the
effectiveness of chemotherapy treatments.
• All but one of the studies that reported treatment response showed similar or better
response in the antioxidant group than in the control group.
• 15 of 17 trials that assessed chemotherapy toxicities, including diarrhea, weight loss,
nerve damage and low blood counts, concluded that the antioxidant group suffered
similar or lower rates of these side effects than the control group.
The authors noted that reducing side effects may help patients avoid having to cut
back on their chemotherapy dosing, interrupt scheduled treatments, or abandon
treatment altogether. This in turn, is likely to favorably impact treatment outcomes. A
recent study of a group of colon cancer patients indicated that those who completed
their full prescribed schedules of chemotherapy had survival rates nearly double those
of patients who abandoned their chemotherapy treatment prematurely.
This new study encourages further exploration of the potential importance of
antioxidant supplements as a means of improving cancer survival.
# # # # # The full study is currently available on line at
http://www.sciencedirect.com/science/journal/03057372. For additional information, or
to schedule an interview with Dr. Block, please contact Leni Kass at 847.229.8911 or
email at Lsk1836@comcast.net.