“Cancer patients who use alternative medicine more than twice as likely to die,” is the stark message from The Independent. Researchers found that people who chose alternative medicine instead of conventional cancer treatments were much less likely to survive for at least five years.
Overall, 78% of people having conventional treatment for cancer survived at least five years, compared to only 55% of people having alternative treatment alone. The difference was biggest for breast cancer, where people who chose alternative therapies were more than five times as likely to die within five years as those who chose conventional treatments.
Because this is an observational study, we don’t know if other factors might have affected people’s survival chances, as well as treatment choice. However, treatment choice seems the most likely explanation.
There are reports that some people find complementary medicines (CAMs) of benefit during cancer treatments. For example, some people have said that acupuncture helped them cope better with the side effects of chemotherapy.
But importantly, the emphasis is very much on the “complementary” and not on the “alternative”. Ignoring medical advice on the treatment choices that potentially offer the most benefit could be fatal.
Where did the story come from?
The study was carried out by researchers from Yale School of Medicine. No funding information was provided. Two of the four researchers had received previous grants from companies involved in conventional cancer treatments, and one received research funding from the organisation 21st Century Oncology.
The study was published in the peer-reviewed Journal of the National Cancer Institute as a “brief communication”, meaning that not all the study data was published. Some additional data is published online.
Most of the UK media ran reasonably accurate and balanced stories. Several – notably the Mail Online and The Sun – speculated on the types of alternative therapy people might have been using. For example, the Mail said: “Breast cancer patients are 5.68 times more at risk if they opt for homeopathy.”
However, the researchers did not record the alternative therapies used, so we don’t know whether homeopathy was one of them. The Mail also refers to “herbs, botanicals, diets or energy crystals.” While these are sometimes promoted as alternative treatments for cancer, again, we don’t know which of them were used by people in this study.
What kind of research was this?
This was an observational case control study. This means researchers identified people with cancer who chose to use alternative therapies (cases) and compared their outcomes with those of people with cancer who chose conventional treatments (controls).
The controls were matched as far as possible with each case based on age, sex, demographics and type of cancer. Observational studies can show trends and links between factors (in this case between type of treatment and length of survival after cancer diagnosis) but cannot prove that one causes the other.
What did the research involve?
Researchers used data from the US National Cancer Database to identify patients with breast, lung, colorectal or prostate cancer, who opted not to receive conventional cancer therapies, but were recorded as having had “other-unproven cancer treatments administered by non-medical personnel”.
These patients were matched with two patients with the same type of cancer, who were similar in other ways, but had opted for conventional treatment. Researchers then looked to see how many people lived for at least five years, comparing those who chose alternative therapies with those who chose conventional cancer treatments.
Researchers only included people who had cancer that had not yet spread from the initial site. This type of cancer is usually treatable by conventional treatments. They also excluded people with stage 4 (advanced) cancer, those whose treatment was intended to be palliative rather than curative, and people whose treatment was unknown.
Researchers found 281 people who matched the criteria and who had opted for alternative therapy only. Of these, 280 were matched to 560 people with the same cancer, who chose conventional cancer treatments.
To minimise the effect of confounding factors, researchers matched people in the study using these criteria:
- cancer type
- stage of cancer
- health insurance – in the US people with health insurance tend to receive a better standard of treatment
- co-morbidities (other illnesses)
- year of diagnosis
In addition, when calculating relative chances of surviving five years, the researcher adjusted their figures to account for the effects of medical and demographic factors.
What were the basic results?
Researchers found that people choosing alternative therapies were more likely to be younger, female, have fewer other ailments, a higher cancer stage, a higher income and education level. Taking all types of cancer together:
- 78.3% of people having conventional cancer treatment lived at least five years (95% confidence interval (CI) 74.2% to 81.8%)
- 54.7% of people having alternative therapies lived at least five years (95% CI 47.5% to 61.3%)
- People were 2.5 times more likely to live for at least five years if they had conventional treatment (hazard ratio (HR) 2.5, 95% CI 1.88 to 3.27)
The type of cancer made a difference, though. This is probably because some cancers can kill quickly without treatment, and treatment is very effective. We can see this in the breast cancer results:
- 86.6% of people who chose conventional treatment for breast cancer lived at least five years (95% CI 80.7% to 90.7%)
- 58.1% of people who chose alternative therapies for breast cancer lived at least five years (95% CI 46% to 68.5%)
- people were 5.68 times more likely to live at least five years if they had conventional treatment for breast cancer (HR 5.68, 95% CI 3.22 to 10.04)
However, for prostate cancer, it made little difference whether people opted for conventional treatment (91.5% lived for at least five years) or alternative treatment (86.2% lived for at least five years).
This is probably because prostate cancer usually grows very slowly in the early stages so few people die. For the first five to 10 years, there’s little difference in those who have conventional treatments and those who have their prostate cancer monitored, with no treatment unless it starts to grow. So, you would not expect to see a difference in a five year study.
How did the researchers interpret the results?
The researchers said: “We found that cancer patients who initially chose treatment with alternative medicine without conventional cancer treatment were more likely to die.”
They added: “Improved communication between patients and caregivers, and greater scrutiny of use of alternative medicine for initial treatment of cancer is needed.”
The results and conclusions of this study are clear: people who choose conventional treatments for cancer (such as surgery, radiotherapy, chemotherapy and hormone treatments) are likely to live longer than those who choose alternative medicine only.
It’s rare for people to choose to ignore conventional treatment completely when faced with a cancer diagnosis. More often, people choose to add complementary therapies to their conventional cancer treatment. This study doesn’t apply to people combining conventional and complementary therapies.
There are some limitations to the study to be aware of:
- Because it is an observational study, it cannot prove that treatment choice (as opposed to other factors) was the sole reason that people who chose conventional treatments lived longer. However, it seems the most likely explanation. The researchers made efforts to balance out other possibly confounding factors. It’s also clear from other studies that conventional cancer therapies work.
- The study might have misclassified some people who started taking alternative therapies when diagnosed, but switched later to conventional treatments. However, as they would be classified in this study as having taken conventional treatments, this suggests that any switchers would only strengthen the study findings, if they were reclassified as having taken alternative medicine.
People who are diagnosed with cancer and want the best chance of surviving should choose conventional cancer therapies. These give the best chance of helping people with cancer to live longer lives. Complementary therapies such as acupuncture and tai chi may help some people but they should never take the place of potentially life-saving treatments such as chemotherapy, surgery and radiotherapy.
Analysis by Bazian
Edited by NHS Website
Links to the headlines
The Independent, 15 August 2017
Mail Online, 15 August 2017
The Sun, 15 August 2017
Links to the science
Journal of the National Cancer Institute. Published online August 10 2017