Antioxidant vitamin supplements help breast cancer patients survive 抗氧化維生素補充劑可幫助乳腺癌患者生存

Editor’s note:

It is not just antioxidants that help cancer patients. The following is only one of the studies that suggest that taking antioxidants during conventional treatments can extend cancer patients’ survival. More studies of this sort have been reported. For instance, Dr. Linus Paul and his colleagues observed that same that cancer patients who took vitamins lived much longer than those who did not.

What the study finds

A 2011 study published in Cancer Epidemiology, Biomarkers and Prevention suggests that taking vitamin supplements after diagnosis may help breast cancer patients to survive.

Antioxidants Considered in the study include vitamin E, vitamin C and multivitamins (some antioxidants in multivitamins). Researchers found that patients taking antioxidant vitamin supplements after diagnosis were less likely to die from breast cancer or have recurrence during a four-year follow-up.

Background

The findings make sense. Antioxidants are known to protect normal cells from being harmed by radiotherapy and chemotherapy. However, some doctors are concerned that antioxidant vitamins can reduce effectiveness of cancer treatments because most treatments kill cancer cells by therapy-induced oxidative stress. And antioxidants are supposed to reduce the oxidative stress. Because of this, they are expected to reduce the efficacy of the treatments.

Study and findings

For the study, Chinese researchers investigated 4877 women aged 20 to 75 years who diagnosed with invasive breast cancer in Shanghai, China between March 2002 and April 2006. The patients were interviewed within six months of diagnosis. And During the follow-up, 444 died and 532 had recurrence.

After adjustment for other factors such as lifestyle socio- demographics, and prognostic factors, the researchers found antioxidant vitamins correlated with 18% reduced risk for death and 22% reduced risk for recurrence.

This association was found in breast cancer patients who either receive chemotherapy or non-chemotherapy only, but did not receive radiotherapy. That is, antioxidants do not help patients treated with radiotherapy.

Conclusion

The study hints that antioxidant vitamin supplementation in the first six months after diagnosis can help reduce risk of death from breast cancer and recurrence.

The findings do not support the current recommendation that breast cancer patients should not use antioxidant vitamins during treatments, the researchers said.

Reference

Sarah Nechuta, Wei Lu, Zhi Chen, Ying Zheng, Kai Gu, Hui Cai, Wei Zheng and Xiao Ou Shu, (2011) Vitamin Supplement Use During Breast Cancer Treatment and Survival: A Prospective Cohort Study. Cancer Epidemiology, Biomarkers and Prevention.