DR. WEEKS’ COMMENT:
It is so hard for them to acknowledge that antioxidants not only do not interfere with cytotoxic effects of chemotherapy but actually improve outcome when given along with chemo — read below 32% vs 39% and 11.1 vs 16 . While not statistically significant, one wonders whether, had the numbers fallen the other way, would the scientists demure about the role of antioxidants?
J Am Coll Nutr. 2005 Feb;24(1):16-21.
Chemotherapy alone vs. chemotherapy plus high dose multiple antioxidants in patients with advanced non small cell lung cancer.
Department of Medical Oncology, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi 110 029, INDIA.
OBJECTIVE: In vitro and animal studies suggest that antitumor effect of chemotherapeutic agents may be enhanced by antioxidants. Therefore, we initiated a clinical study to test the efficacy of high-dose multiple antioxidants (vitamins C, E and beta carotene) as an adjunct to chemotherapy (paclitaxel and carboplatin) in non-small-cell lung cancer.
METHODS: 136 patients of stage IIIb and stage IV NSCLC were randomized to receive chemotherapy (paclitaxel and carboplatin) alone (chemotherapy arm, n = 72) or chemotherapy in combination with ascorbic acid 6100 mg/day, dl-alpha-tocopherol (vitamin E) 1050 mg/day and beta-carotene 60 mg/day (combination arm, n = 64). Survival were calculated by the Kaplan-Meier method and compared using the log-rank test.
RESULTS: An overall response rate (RR) of 33% was observed in chemotherapy arm with 24 patients showing a partial response (PR) and none showing a complete response (CR). In combination arm the overall RR was 37% with 24 patients showing PR and two showing CR. The median survival times in chemotherapy arm and combination arm were nine and 11 months respectively. The overall survival (OS) rates in chemotherapy arm and combination arm at one year were 32.9% and 39.1%, and at two years, 11.1% and 15.6% respectively. None of these differences were statistically significant (p = 0.20). Toxicity profiles were similar in both arms.
CONCLUSIONS: These results do not support the concern that antioxidants might protect cancer cells from the free radical damage induced by chemotherapy. Larger trials are needed to demonstrate whether high-dose multiple antioxidants in conjunction with chemotherapy increase the response rates and/or survival time in advanced lung cancer.