US – Women in early stages of breast cancer using dietary supplements and various types of complementary and alternative therapies are less likely to start chemotherapy treatments prescribed to patients who do not use these therapies, according to a study published in JAMA Oncology.

The study has been led by Heather Greenlee, a researcher at the University of Columbia in favor of such alternative therapies as a complement to traditional medicine. Thus, the investigation could have “conflicts of interest”. Despite these potential conflicts, the results indicate that the use of these medical treatments not associated with an increased risk of rejecting chemical therapy that slows the progression of cancer and increase survival.

Not all women with breast cancer are recommended to begin chemotherapy treatment. The decision involves psycho-social factors, beliefs, clinical and demographic characteristics. The use of complementary and alternative therapies among patients with breast cancer has increased over the past two decades, but few studies have evaluated how it ultimately affects when it comes to go for chemotherapy, according to the study.

Heather and her team have studied a group of 685 women with early-stage breast cancer who were recruited from multiple locations. All of them were under 70 years old and suffering from invasive tumor nonmetastatic breast cancer.

Most, 598 women (87%) used alternative therapies at baseline: vitamins and minerals; herbs and plants, other natural products and self-care of body and mind.  38% were users of three or more kinds of these therapies.

In total, 306 women were instructed to be treated with chemotherapy and the rest was given a discretionary recommendation for this treatment.

At twelve months, most women indicated they started chemotherapy treatment (272, 89%). The group of women for whom chemotherapy was discretionary had a much lower rate of onset, 36% (135 women).

Dietary supplements

Self-care of body and mind were not related to the initiation of chemotherapy. However, consumption of dietary supplements and other alternative therapies were associated with a lower likelihood of starting with chemotherapy.

The researchers concluded that although most women indicated began chemotherapy treatment, 11% (34 of 306) did not. A cautious interpretation of the results may indicate to oncologists that it is beneficial to know if their patients are using alternative therapies, especially dietary supplements.

For authors, it is important to consider other possible explanations for their results, and believe that it is unclear whether the association between the use of alternative therapies and non-initiation of chemotherapy reflects patterns making long-term decisions.

In a commentary independent of the study, Robert Zachariae, a researcher at Aarhus University Hospital (Denmark), has highlighted the urgent need for oncologists to be trained to learn to talk to their patients about possible alternative therapies that may interfere with treatment, respectfully without making them feel judged.