Battling Bunk: Cancer Misinformation’s Impact on Patients and How Providers Can Respond

The “infodemic” that stalks the ongoing COVID-19 pandemic might be the most prominent recent example of the harmful impact of health misinformation, but it is in no way a unique phenomenon—or, for that matter, a new one.1 Complex and frightening diseases, like cancer, have long been the target of medical misinformation and ineffective treatments. In addition, the degree to which the social networks of Web 2.0 amplify inaccurate cancer information can be staggering. Look no further than the 2020 American Society of Clinical Oncology (ASCO) Cancer Opinion Survey, which found that over a third of US adults believe that cancer can be cured through alternative therapy alone.2 What does the normalization of alternative therapy mean for cancer patients and how can medical professionals respond in a way that is both effective and respectful? Let us begin by defining important terms.

Therapies that are not part of the standard of care include “alternative” and “complementary” therapies, sometimes combined under the umbrella term “complementary and alternative medicine” or CAM. While similar, these terms are distinct. Complementary therapies are used together with the standard of care, often for symptom management.3 For example, if a cancer patient manages their chemotherapy-induced neuropathy with acupuncture but continues to follow with their oncology team’s prescribed treatment, acupuncture would constitute a complementary therapy. Conversely, alternative therapies are used in lieu of the standard of care.4 If our hypothetical patient opted to treat their disease exclusively with acupuncture and abstain from medically indicated treatment, acupuncture would become an alternative therapy. In short, the way in which therapies are applied largely determines whether they are alternative or complementary. The NIH reports that about 1 in 3 adults and 1 in 8 children in the US use CAM, suggesting that while it may not be part of the standard of care, CAM is well within the cultural mainstream.5

Despite its prevalence, CAM use poses risks of physical and financial harm. Mortality rates among cancer patients who use CAM are significantly higher than those who do not.6,7 Even seemingly benign herbal supplements used as complementary therapies are known to have adverse interactions with chemotherapy.8 The financial harm associated with CAM use can also be high, although research into the topic remains sparse.9 Together with other researchers, I have analyzed hundreds of online fundraising campaigns written by individuals seeking alternative cancer therapy. Their stories hint to acute financial strain. One person solicited donations “so their family does not have to take a mortgage out on their home to fund it.” Another sought alternative therapy despite them being someone “whose savings are gone, with credit card debt [in the thousands].” Yet another individual explained that they were forced to turn to online crowdfunding to help pay for alternative therapies since they “cannot get funds or loans from banks” due to their already poor credit. Avoiding low-quality cancer care is key to minimizing financial toxicity.10 Tragically, using CAM does the exact opposite; it often involves substantial out-of-pocket costs and correlates with poorer health outcomes.

Engagement with cancer misinformation often begins with good intentions. After receiving what about half of US adults consider to be their most dreaded diagnosis, patients and caregivers often turn to the internet for answers and hope.11 Many find community through online support groups on social media. Unfortunately, much of the information shared in these spaces is inaccurate. In a 2021 study by Johnson and colleagues, cancer experts reviewed the 50 most popular English-language social media articles on breast, lung, colorectal, and prostate cancer to evaluate their veracity and safety. Over a third contained misinformation and 30.5% contained statements classified as medically or financially harmful.12 Previous research has established that falsehoods spread further, faster, and to a broader audience than truth, and there appears to be no difference with cancer.13 Unfortunately, Johnson et al found that engagement (eg, likes and shares) was significantly higher for misinformation than for fact, and higher still for articles with harmful misinformation.12 Algorithms designed to maximize the amount of time users spend on platforms contribute to the problem by selecting for emotional reactivity rather than truth.14 Misinformation is often presented in emotionally compelling narratives, which research has found to be highly memorable and persuasive.15 To make matters worse, many CAM providers gain credibility by co-opting scientific medical language, a behavior known as “scienceploitation,” and citing publications in predatory journals.15 Their false claims are, in turn, referenced by others online. For example, one crowdfunding campaign emphasized that a clinic provided “an alternative cancer therapy ... that has a 98% success rate.” Another described a CAM practitioner as “a pioneer” who “has been successfully treating cancer patients” for decades. Repeated exposure to these narratives raises the profile of ineffective therapies, and soon familiarity is easily mistaken for validity.16

This constellation of factors means that too often, the internet’s reply to a sincere request for useful cancer information is an intoxicating cocktail of hearsay and predatory advertising crafted for clicks.

Fortunately, medical professionals are well positioned to counter this maelstrom of misinformation. A national survey of US adults conducted in May of 2020 found that more than 90% trusted hospitals and physicians.18 While public confidence has decreased since then, the Pew Research Center’s 2021 survey found that 78% of US adults still report either “a great deal” or “a fair amount” of confidence that medical scientists act in the best interests of the public.17 Strong interpersonal skills appear to be key to this trust; patients report that they have confidence in physicians who listen, deal honestly, express caring, and are considerate of their unique circumstances.19,20 The importance of a strong therapeutic alliance cannot be overstated. Although many cancer patients use CAM, a fear of criticism often keeps them from telling their doctor about it.21 Moreover, patients’ motivations for pursuing CAM are complex and can change over time,22 Many are drawn to CAM because they want holistic care, so it is encouraging that a growing number of cancer hospitals are finding ways to safely and effectively integrate complementary therapy into care plans.22,23 Others patients grow frustrated with conventional therapies’ adverse effects or feel that they must continue to fight on after the standard of care has proven ineffective.22 A growing number of learning resources, including those available through the American Society for Radiation Oncology (ASTRO), teach how to sensitively navigate complicated clinical scenarios.24 Training such as these can help medical providers build upon broad public trust and facilitate open and empathetic clinical conversations.

Medical professionals can also connect with cancer patients on social media.25 When incorrect information is shared, either in clinic or online, clear correction is shown to be an effective response, though repetition may be necessary.26 Just as personal stories are used to spread misinformation, they can also be used to illustrate of the harms of alternative therapy and celebrate the efficacy of evidence-based care. When discussing treatment options with patients, find ways to teach visually or experientially. Educational materials, especially those with images and pictograms, have proven highly effective at communicating information and countering anecdotes.27 By listening to patients, connecting with them emotionally and digitally, and teaching powerfully, cancer care providers can respectfully and effectively respond to misinformation.


  1. Director-General’s remarks at the media briefing on 2019 novel coronavirus on 8 February 2020. Accessed March 26, 2020.
  2. The Harris Poll. ASCO 2020 National Cancer Opinions Survey. The American Society of Clinical Oncology; 2020:61. Accessed May 24, 2022.
  3. Complementary Medicine. In: NCI Dictionary of Cancer Terms. National Cancer Institute. Accessed May 24, 2022.
  4. Alternative Medicine. In: NCI Dictionary of Cancer Terms. National Cancer Institute. Accessed May 24, 2022.
  5. Complementary, Alternative, or Integrative Health: What’s in a Name? NCCIH. Published April 2, 2019. Accessed March 24, 2020.
  6. Johnson SB, Park HS, Gross CP, Yu JB. Use of alternative medicine for cancer and its impact on survival. J Nat Cancer Inst. 2018;110(1):121-124.
  7. Johnson SB, Park HS, Gross CP, Yu JB. Complementary medicine, refusal of conventional cancer therapy, and survival among patients with curable cancers. JAMA Oncol. 2018;4(10):1375-1381. doi:10.1001/jamaoncol.2018.2487
  8. Ambrosone CB, Zirpoli GR, Hutson AD, et al. Dietary supplement use during chemotherapy and survival outcomes of patients with breast cancer enrolled in a cooperative group clinical trial (SWOG S0221). JCO. 2019;38(8):804-814. doi:10.1200/JCO.19.01203
  9. Huebner J, Prott FJ, Muecke R, et al. Economic evaluation of complementary and alternative medicine in oncology: is there a difference compared to conventional medicine? Med Princip Pract. 2017;26(1):41-49. doi:10.1159/000450645
  10. Carrera PM, Kantarjian HM, Blinder VS. The financial burden and distress of patients with cancer: Understanding and stepping-up action on the financial toxicity of cancer treatment. Cancer J Clin. 2018;68(2):153-165. doi:10.3322/caac.21443
  11. Barker AD, Jordan H. Holland-Frei Cancer Medicine. 6th ed. (Kufe DW, Pollock RE, Weichselbaum RR, et al, eds.). BC Decker; 2003. Accessed May 18, 2022.
  12. Johnson SB, Parsons M, Dorff T, et al. Cancer misinformation and harmful information on Facebook and other social media: a brief report. J Natl Cancer Inst. Published online July 22, 2021:djab141. doi:10.1093/jnci/djab141
  13. Vosoughi S, Roy D, Aral S. The spread of true and false news online. Science. 2018;359(6380):1146-1151. doi:10.1126/science.aap9559
  14. Merrill JB, Oremus W. Five points for anger, one for a ‘like’: How Facebook’s formula fostered rage and misinformation. The Washington Post. Published October 26, 2021. Accessed May 24, 2022.
  15. Caulfield T, Marcon AR, Murdoch B, et al. Health misinformation and the power of narrative messaging in the public sphere. Can J Bioethics/Revue canadienne de bioéthique. 2019;2(2):52-60.
  16. Hassan A, Barber SJ. The effects of repetition frequency on the illusory truth effect. Cog Res Princ Implic. 2021;6(1):38. doi:10.1186/s41235-021-00301-5
  17. Kennedy B, Tyson A, Funk C. Americans’ Trust in Scientists, Other Groups Declines. Pew Research Center; 2022:1. Accessed May 24, 2022.
  18. Ognyanova K, Perlis RH, Baum MA, et al. The State of the Nation: A 50-State COVID-19 Survey. Northeastern University, Harvard University, Rutgers, University, and Northwestern University; 2020:14. Accessed May 24, 2022.
  19. Hillen MA, de Haes HC, Smets EM. Cancer patients’ trust in their physician—a review. Psycho‐oncology. 2011;20(3):227-241. doi:10.1002/pon.1745
  20. Thom DH, Hall MA, Pawlson LG. Measuring patients’ trust in physicians when assessing quality of care. Health Aff. 2004;23(4):124-132. doi:10.1377/hlthaff.23.4.124
  21. Davis EL, Oh B, Butow PN, Mullan BA, Clarke S. Cancer patient disclosure and patient-doctor communication of complementary and alternative medicine use: a systematic review. Oncologist. 2012;17(11):1475-1481. doi:10.1634/theoncologist.2012-0223
  22. Peterson J, Wilson T, Gruhl J, et al. Timing and Motivations for Alternative Cancer Therapy: Insights from a Crowdfunding Platform. JMIR Cancer. [In press];[In press]. doi:10.2196/34183
  23. Yun H, Sun L, Mao JJ. Growth of integrative medicine at leading cancer centers between 2009 and 2016: a systematic analysis of NCI-designated comprehensive cancer center websites. JNCI Monographs. 2017;2017(52). doi:10.1093/jncimonographs/lgx004
  24. Dharmarajan K, Tulsky J. Improving doctor-patient communication skills in radiation oncology. ASTRO Academy. Published online February 7, 2017. Accessed May 24, 2022.
  25. Peterson JS, Swire-Thompson B, Johnson SB. What is the alternative? Responding strategically to cancer misinformation. Future Oncol. Published online June 21, 2020. doi:10.2217/fon-2020-0440
  26. Swire-Thompson B, Cook J, Butler LH, Sanderson JA, Lewandowsky S, Ecker UKH. Correction format has a limited role when debunking misinformation. Cog Res Princ Implic. 2021;6(1):83. doi:10.1186/s41235-021-00346-6
  27. Fagerlin A, Wang C, Ubel PA. Reducing the influence of anecdotal reasoning on people’s health care decisions: is a picture worth a thousand statistics? Med Decis Making. 2005;25(4):398-405. doi:10.1177/0272989x05278931

John Peterson, MD

Radiation oncology resident at the Moffitt Cancer Center in Tampa, FL.