CAM users less likely to start chemotherapy for breast cancer
May 18 2016
Women with breast cancer are less likely to start chemotherapy when using certain complementary or alternative medicines or therapies (CAM), a US study has proposed.
In particular, among women for whom chemotherapy was indicated, those taking dietary supplements or who had a high CAM index were less likely to start chemotherapy than those who did not use CAM treatments.
Researchers were looking for predictors of breast cancer treatment initiation, and considered five CAM modalities: vitamins and/or minerals, herbs and/or botanicals, other natural products, mind-body self-practice, mind-body practitioner-based practice (such as yoga, meditation, qi gong, acupuncture and massage).
The 12-month study involved a cohort of 685 women with a mean age of 59 years who had non metastatic invasive breast cancer. Of these women, at the start of the study, 598 (87%) were using at least one form of CAM, and 30 were using five or more different treatments. There was no association where chemotherapy was discretionary, and the study found no correlation between chemotherapy initiation and mind-body practices where chemotherapy was indicated.
The researchers had anticipated that CAM use would be associated with the discretionary chemotherapy group “because there is more leeway in the decision making process.” However, the study found this was not the case. “Instead, in the group with a clear clinical indication for chemotherapy, users of CAM were significantly overrepresented among the relatively small group that did not receive this indicated treatment.”
Earlier analysis of the same cohort had found that women were less likely to start chemotherapy if they were older, had more negative beliefs about chemotherapy effectiveness, and more concerns about adverse effects. “This analysis identifies dietary supplement use as a potential new risk factor for chemotherapy non-initiation,” said the researchers.
They have recommended that “oncologists should discuss CAM use with their patients during the chemotherapy decision-making process as CAM use, especially dietary supplement use, may be an indicator of patients at risk for non-initiation of chemotherapy.” Being aware about the patient’s use of CAM can prompt further discussions about the patient’s expectations regarding chemotherapy.
Commenting on the study, Cancer Research UK’s Dr Emma Smith said there was evidence that complementary therapies can improve quality of life, and that it was every woman’s right to choose whether or not to have chemotherapy as part of their breast cancer treatment. “But in making their decision they should not think of these therapies as a substitute for conventional cancer medicines, which have been researched in well-designed clinical trials, and are proven to be effective.”
H Greenlee et al. 'Association Between Complementary and Alternative Medicine Use and Breast Cancer Chemotherapy Initiation The Breast Cancer Quality of Care (BQUAL) Study'. JAMA. Published online May 12 2016