While most patients with cancer primarily choose conventional treatments, such as chemotherapy and radiation therapy, others rely solely on alternative medicine, which can include herbs and supplements among other things. Now, new findings published in the Journal of the National Cancer Institute reveal that, depending on the type of cancer, reliance on only nontraditional therapies may boost an individual’s risk of death as much as five or six times, reports MedPage Today

For the study, researchers reviewed data from the National Cancer Database for 2004 to 2013 to identify factors associated with patient preference for alternative medicine and to compare survival rates between those who chose these unproven therapies and those who opted for conventional treatment. Scientists specifically focused on individuals with the four most common cancers: breast, prostate, lung and colorectal.

According to the information collected, those in the alternative medicine group were younger, better educated, more likely to have breast or lung cancer at Stage II or III of the disease, live in Intermountain West and Pacific regions and have lower comorbidity scores.

Researchers identified 280 patients who selected alternative medicine as initial treatment. Next, researchers matched each person with two similar patients who chose conventional therapy instead. (Overall, the study included 840 people.) The median follow-up was about five and a half years.

Findings showed that those in the alternative medicine cohort experienced a significantly worse five-year survival rate overall (54.7 percent versus 78.3 percent) than those who weren’t in that group. Regarding the individual types of cancer, scientists also linked alternative medicine with worse five-year survival rates for patients with breast, lung and colorectal cancer—but not those with prostate cancer.

“[Health care providers] are taught to respect patients’ wishes, especially with regard to treatment choices,” said James Hu, MD, director of Yale’s Prostate and Genitourinary Cancer Radiotherapy Program and the study’s senior author. “If patients make an informed decision, because of patient autonomy, they can do whatever they want. We’re always advising them; we can’t make them do anything. What this study says is that we can advise that if they choose an alternative and unproven treatment, they are more likely to die than if they go with [conventional] therapy.”

Hu said the study’s biases highly favored alternative treatment because the cohort consisted of younger and more affluent cancer patients with fewer related illnesses. But these participants didn’t do better than those who selected traditional care. His big worry is that young patients who could potentially be cured of cancer are being misled by alternative medicine practitioners into trying only unconventional and ineffective therapies.

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