Perception of risk and communication among conventional and complementary health care providers involving cancer patients' use of complementary therapies: a literature review

Background: Communication between different health care providers (conventional and complementary) and cancer patients about their use of complementary therapies affects the health and safety of the patients. The aim of this study was to examine the qualitative research literature on the perception of and communication about the risk of complementary therapies between different health care providers and cancer patients. Methods: Systematic searches in six medical databases covering literature from 2000 to 2015 were performed. The studies were accessed according to the level of evidence and summarized into different risk situations. Qualitative content analysis was used to analyze the text data, and the codes were defined before and during the data analysis. Results: Twenty-nine papers were included in the primary analysis and five main themes were identified and discussed. The main risk situations identified were 1. Differences in treatment concepts and philosophical values among complementary and conventional health care providers. 2. Adverse effects from complementary products and herbs due to their contamination/toxicity and interactions with conventional cancer treatment. 3. Health care physicians and oncologists find it difficult to recommend many complementary modalities due to the lack of scientific evidence for their effect. 4. Lack of knowledge and information about complementary and conventional cancer treatments among different health care providers. Conclusion: The risk of consuming herbs and products containing high level of toxins is a considerable threat to patient safety (direct risk). At the same time, the lack of scientific evidence of effect for many complementary therapies and differences in treatment philosophy among complementary and conventional health care providers potentially hinder effective communication about these threats with mutual patients (indirect risk). As such, indirect risk may pose an additional risk to patients who want to combine complementary therapies with conventional treatment in cancer care. Health care providers who care for cancer patients should be aware of these risks.