Integrative Oncology

The Society for Integrative Oncology

The Society for Integrative Oncology (SIO) states that it was established in 2003 and describes itself as a multidisciplinary professional organisation whose mission is to advance evidence-based, comprehensive integrative healthcare for people affected by cancer. Its stated membership includes oncologists, nurses, psychologists, social workers, nutritionists, naturopathic doctors, herbalists, acupuncturists, yoga therapists and massage therapists. These are the society's own statements. The sources reviewed do not trace the field before 2003 or date the first use of the term.

Use of complementary approaches by people with cancer

A systematic review and meta-analysis of surveys published up to January 2009 included 152 studies from 18 countries and more than 65,000 adults with cancer. Heterogeneity was high. The combined prevalence of current complementary and alternative medicine use was 40%, and the authors' meta-analysis suggested a rise from an estimated 25% in the 1970s and 1980s to 32% in the 1990s and 49% after 2000. The authors noted that the overall figure was lower than often claimed. The abstract does not separate clinic-based integrative care from self-directed use.

Consensus definition and guidelines

A 2017 paper by an international panel noted that integrative oncology had been defined in different ways and that no definition was widely accepted. It developed one through a literature analysis, an interdisciplinary expert panel and surveys. In the same year the SIO published clinical practice guidelines covering integrative therapies for symptoms of breast cancer and its treatment, which the American Society of Clinical Oncology (ASCO) endorsed in 2018 after review by its own expert panel.

Later guidelines followed. SIO and ASCO jointly published a guideline on cancer pain in September 2022 and one on anxiety and depression in 2023, and ASCO published an update on cancer-related fatigue in 2024 with the SIO named in its title. A 2024 commentary says the SIO Education Committee was established in 2021 and has since worked on training modules and a curriculum.

Integrative, complementary and alternative

The National Center for Complementary and Integrative Health (NCCIH) uses 'complementary' for a non-mainstream approach used together with conventional medicine and 'alternative' for one used in place of it. It describes 'integrative' health as bringing conventional and complementary approaches together in a coordinated way. The National Cancer Institute (NCI) draws the same line for cancer: complementary medicine is used along with standard treatment, while alternative medicine is used instead of it, for example a special diet used instead of prescribed cancer drugs.

The consensus definition

The 2017 consensus definition describes integrative oncology as a patient-centred, evidence-informed field of cancer care that uses mind and body practices, natural products and lifestyle modifications from different traditions alongside conventional cancer treatment. It states aims of improving health, quality of life and clinical outcomes across the cancer care continuum and of supporting people to take an active part before, during and beyond treatment. It is one panel's definition, and its authors noted that none had been widely accepted before it.

Terms used in registry studies

Studies of complementary medicine in cancer registries do not necessarily describe integrative oncology as defined above. A 2018 analysis of a United States national cancer database identified complementary medicine through a registry category for unproven cancer treatments administered by non-medical personnel, and the matched sample was small, with 258 patients in the complementary medicine group. Findings from such data concern a differently defined exposure and should not be read as findings about guideline-based supportive care.

Settings and practitioners

The sources describe integrative oncology as a field spanning several professions and not a single technique. The SIO's stated membership combines oncologists and other clinicians with complementary therapy practitioners. A 2024 SIO commentary cites a rise in the share of National Cancer Institute-designated comprehensive cancer centres offering integrative oncology services from 50% in 2009 to 80% in 2016, a figure it takes from another paper that was not opened for this record. The sources reviewed do not describe a standard consultation format, so no typical session is described here.

Interventions named in the guidelines

The SIO-ASCO guidelines name specific interventions and not a package. They include acupuncture, acupressure, reflexology, massage and hypnosis for pain; mindfulness-based interventions, yoga, relaxation, music therapy, tai chi or qigong, acupuncture, reflexology and inhaled aromatherapy for anxiety or depression; and exercise, cognitive behavioural therapy, mindfulness-based programmes, tai chi or qigong, yoga, acupressure, moxibustion and American ginseng for fatigue. Which items are recommended, for which symptom and at which stage of care differs by guideline and is set out under research and evidence.

Training and regulation

A survey of 19 integrative oncology training programmes, reported by the SIO Education Committee, found 14 in North America, two in Germany, two in Israel and one in Korea. Length ranged from 3.5 to 1,000 hours (median 16.5), most were online only, and half were aimed at physicians alone. The committee identified an education gap, including the lack of a standard textbook and core curriculum, and is working on both. The sources reviewed identify no statutory regulation or single training standard for the term, and this record does not cover jurisdiction-specific rules.

Symptom and quality-of-life aims

The guidelines address named symptoms. The 2022 pain guideline's outcomes of interest were pain intensity, symptom relief and adverse events; the 2023 guideline covers anxiety and depression symptoms in adults with cancer; the 2024 update covers cancer-related fatigue; and the breast cancer guideline covered anxiety and stress, mood, fatigue, quality of life, chemotherapy-induced nausea and vomiting, lymphoedema, chemotherapy-induced peripheral neuropathy, pain and sleep disturbance. The consensus definition also states broader aims of improving health, quality of life and clinical outcomes.

Claims about cancer control

The guideline abstracts reviewed report symptom, quality-of-life and adverse-event outcomes. They do not recommend any integrative therapy as a way of controlling tumours. The NCI states that no studies prove that any special diet, food, vitamin, mineral, dietary supplement, herb or combination of these can slow cancer, clear it or keep it from coming back. Claims of that kind, where individual practitioners or products make them, sit outside the guideline evidence described on this page.

Cancer pain: SIO-ASCO guideline (2022)

The 2022 guideline searched systematic reviews, meta-analyses and randomised trials published from 1990 to 2021 and identified 227 relevant studies. For adults, it says acupuncture should be recommended for aromatase inhibitor-related joint pain. Acupuncture, reflexology or acupressure may be recommended for general cancer pain or musculoskeletal pain, hypnosis for procedural pain, and massage for pain during palliative or hospice care. The panel based these on an intermediate level of evidence, with benefit outweighing risk and a moderate strength of recommendation.

For other mind-body interventions and natural products, the panel judged the quality of evidence low or inconclusive, and it found insufficient or inconclusive evidence to make recommendations for children. Its abstract states that more research is needed. The recommendations apply to the named pain indications and should not be extended to other symptoms or techniques.

Anxiety and depression: SIO-ASCO guideline (2023)

The 2023 guideline drew on 110 studies (30 systematic reviews and 80 randomised trials) published from 1990 to 2023. During active treatment it made recommendations for mindfulness-based interventions, yoga, relaxation, music therapy, reflexology and inhaled aromatherapy for anxiety symptoms, and after treatment for mindfulness-based interventions, yoga, acupuncture, tai chi or qigong and reflexology. For depression symptoms it recommended mindfulness-based interventions, yoga, music therapy, relaxation and reflexology during treatment, and mindfulness-based interventions, yoga and tai chi or qigong afterwards.

Cancer-related fatigue: ASCO-SIO update (2024)

The 2024 update reviewed 113 randomised trials published from 2013 to 2023. It found that exercise, cognitive behavioural therapy and mindfulness-based programmes improved fatigue both during and after treatment, that tai chi, qigong and American ginseng showed benefit during treatment, and that yoga, acupressure and moxibustion helped after treatment. Other dietary supplements did not improve fatigue. The panel rated certainty and quality of evidence as low to moderate, advised against L-carnitine and found insufficient evidence for or against other psychosocial, integrative or pharmacological interventions.

Breast cancer symptoms: SIO guideline (2017) and ASCO endorsement (2018)

The SIO breast cancer guideline drew on randomised trials published from 1990 to 2015. ASCO's expert panel judged its recommendations clear, thorough and based on relevant evidence, and endorsed it with added discussion. Music therapy, meditation, stress management and yoga were recommended for anxiety or stress; meditation, relaxation, yoga, massage and music therapy for depression or mood disorders; meditation and yoga for quality of life; and acupressure and acupuncture for chemotherapy-induced nausea and vomiting.

Acetyl-L-carnitine was not recommended to prevent chemotherapy-induced peripheral neuropathy because of a possibility of harm, and the guideline found no strong evidence for ingested dietary supplements to manage treatment-related adverse effects.

What the guidelines can and cannot support

Each guideline is specific to a symptom, a stage of care and named interventions, and each states limits. The pain guideline rested on intermediate-level evidence, the fatigue update rated certainty as low to moderate, and the anxiety and depression guideline lists risk of bias, non-standardised therapies, limited diversity in study samples and a lack of active control conditions as limits of the evidence base.

PubMed searches run for this record did not locate a randomised trial or systematic review testing integrative oncology as a whole programme against usual care for survival. The evidence reviewed concerns individual therapies and symptoms. That search used abstracts only and was not exhaustive, so a reviewer should check the gap.

Authorship of the guidance

The guidelines were produced by the SIO with ASCO, or, for breast cancer, by the SIO and then endorsed by ASCO. The SIO is the specialty's own professional society. According to the abstracts of the pain and anxiety guidelines, the panels also included medical, radiation, surgical and palliative oncology, nursing, social science and patient advocacy members. Authorship by the specialty's own society is a point for readers to weigh and does not by itself indicate bias.

Implementation and knowledge gaps

The 2024 SIO education commentary reports a survey of about 350 health professionals, run by the Multinational Association of Supportive Care in Cancer and the SIO, which found that people were not referred to integrative medicine practitioners because of the professionals' limited knowledge of appropriate and safe integrative therapies. It also says people with cancer often do not tell their care team about their use, citing fear of judgment or a belief that it is unimportant.

Alternative use instead of treatment: 2018 JNCI study

A 2018 analysis in the Journal of the National Cancer Institute identified 281 patients with non-metastatic breast, prostate, lung or colorectal cancer who chose alternative medicine as their only anticancer treatment. Compared with 560 matched patients who received conventional treatment, alternative medicine use was associated with a higher risk of death (hazard ratio 2.50, 95% confidence interval 1.88 to 3.27), with subgroup ratios of 5.68 for breast, 2.17 for lung and 4.57 for colorectal cancer. The authors described such use for curable cancer as rare. The design was observational, so the association alone does not establish cause.

Complementary medicine and refused treatment: 2018 JAMA Oncology study

A second 2018 analysis compared 258 patients using complementary medicine alongside at least one conventional treatment with 1,032 matched controls. The complementary medicine group refused surgery (7.0% against 0.1%), chemotherapy (34.1% against 3.2%), radiotherapy (53.0% against 2.3%) and hormone therapy (33.7% against 2.8%) more often. Hazard ratio for death was 2.08 (1.50 to 2.90) without treatment delay or refusal in the model and 1.39 (0.83 to 2.33) with it, and the authors concluded that the risk appeared mediated by refusal. The exposure was a registry category of unproven treatments, not guideline-based care.

Supplements, herbs and drug interactions

The NCI states that herbal supplements may be harmful alone, with other substances or in large doses, and that products that seem safe could interfere with cancer treatment. Its health professional summary reports that St. John's wort lowered levels of some anticancer drugs, including the active metabolite of irinotecan and imatinib, and that antioxidant supplements taken during chemotherapy or radiation were linked in some studies to worse outcomes. It adds that research on such interactions is limited.

A systematic review of biologically based complementary medicines reported that about half of people with cancer do not tell their doctors about their use and that interactions between drugs and herbs or nutrients are known.

Care boundary

The sources place integrative approaches alongside cancer treatment and not in its place. The NCI advises people with cancer to talk with their doctor or nurse before using any complementary approach. Decisions about starting, stopping or changing surgery, drug therapy, radiotherapy or hormone therapy belong with the treating oncology team, and new or worsening symptoms during treatment are a reason to contact that team promptly.