The use of complementary medicine by patients with four common cancers (breast, prostate, lung or colorectal) was associated with refusal of conventional cancer treatment and with a greater risk of death, although the difference in survival may be alleviated by adherence to all recommended conventional cancer therapies, according to research published in JAMA Oncology

Complementary medicine is intended to be used in addition to conventional cancer therapy.

Patients use a wide variety of complementary medicine, which can include herbs and botanicals, vitamins and minerals, traditional Chinese medicine, specialized diets, homeopathy and naturopathy, to improve their quality of life and with the hope of prolonging it.

This study used a large national database to examine the use of complementary medicine by patients and delays in, or refusal of, conventional cancer therapies - From among 1.9 million patients in the National Cancer Database, 258 patients who used complementary medicine were compared with 1,032 who didn't; patients were diagnosed with nonmetastatic breast, prostate, lung or colorectal cancer between 2004 and 2013.

Use of complementary medicine (defined as "other-unproven: cancer treatments administered by nonmedical personnel") in addition to at least one conventional cancer therapy, which was defined as surgery, radiotherapy, chemotherapy or hormone therapy (exposures); overall survival, adherence to treatment and patient characteristics (outcomes).

This was an observational study.

Researchers were not intervening for purposes of the study and cannot totally control for all the natural differences that could explain the study results

The use of complementary medicine by patients was likely understated because patients are often hesitant to report its use to their clinicians; other factors unaccounted for could have influenced survival; and there are inherent limitations in the study's design.

Source: JAMA Oncology