As they say, “absence of evidence is not evidence of absence.” Many alternative therapies, once believed by conventional medical practitioners to be merely placebos, have now been shown to have proven therapeutic value (eg, acupuncture, numerous botanical extracts, meditation).
In their editorial on cancer quackery, Dr. Cassileth and Mr. Yarett review some of the better-known examples of unproven therapies that some practitioners claim have anticancer efficacy. Although the number of patients who forgo or delay evidence-based treatments in lieu of promising-sounding alternative approaches is unknown, the majority of conventional oncology practitioners have had patients who chose this option. Unfortunately, in most cases, delaying or forgoing proven oncologic therapies (chemotherapy, surgery, radiation therapy, etc) leads to poorer cancer-specific outcomes.
Why do some patients choose nonconventional or alternative approaches to treating their disease? Some of the reasons I have heard from patients have included:
• The belief that nonconventional therapies are both effective and less toxic than conventional therapies.
• The belief that the body can eradicate cancer on its own by stimulating inherent physiologic mechanisms (ie, stimulation of the immune system, reduction of inflammation, etc)
• Having more faith in nonconventional practitioners and therapies.
• Conspiracy theories claiming that the conventional medical establishment purposely withholds curative treatments and suppresses research on the known benefits of alternative therapies.
The individuals who promote these beliefs often profit from them by marketing therapies that are not supported by high-quality, rigorous scientific research. It is easy to understand how some patients, after being diagnosed with a serious medical condition such as cancer, can fall prey to the lure of encouraging results touted by the providers who offer these treatments. Medical quackery feeds on the susceptibility of those who want to believe that there is a quick, nontoxic, “natural” alternative to conventional treatments.
However, it is important to recognize that not all therapies categorized as “alternative,” “nonconventional,” or “unconventional” are completely ineffective. They simply may not be effective at treating a specific condition, although they may be very effective in treating other conditions. (For example, acupuncture has not been proven to improve cancer-specific outcomes-but it has been proven to be effective in the management of chemotherapy-induced nausea and vomiting.)
Many nonconventional therapies have, in fact, been scientifically validated to be effective in the management of numerous conditions and symptoms. (For instance, acupuncture has been shown to help combat radiation-induced xerostomia as well as chemotherapy-induced nausea and vomiting; and meditation helps to reduce anxiety, stress, pain, nausea, and more). The distinction between nonconventional therapies (when used in the settings just mentioned) and quackery is that these therapies are being used in an evidence-based manner, instead of or in addition to conventional treatments, for the management of side effects and symptoms.
As an integrative oncologist, in addition to conventional oncologic therapies, I commonly recommend nonconventional therapies (eg, acupuncture, massage, botanical compounds, etc) to my cancer patients. They understand that the purpose of these therapies is to help them manage side effects and symptoms, with likely no direct anticancer activity. However, these therapies can indirectly improve cancer-specific outcomes by enabling patients to better tolerate their prescribed, conventional treatment. Still, as with all unproven associations and claims, we should not overpromise and tell patients that a particular therapy or lifestyle modification will improve outcomes. In the setting of cancer quackery, therapies (eg, shark cartilage, Essiac tea, etc) are extolled as having anticancer activity when their efficacy in this regard has not been proven.
One area of controversy that comes up often in integrative oncology circles is whether or not there is an association between chronic stress and cancer-specific outcomes. Dr. Cassileth asserts that the association between chronic stress and cancer development, progression, and recurrence has not been definitively established. Those who support this view might categorize as quackery the claim that stress reduction (eg, through lifestyle changes, mind-body therapies, etc) can improve cancer-specific outcomes.
Those who believe that chronic stress and cancer are linked cite data that support this claim. In particular, there are clinical studies that report improvements in cancer-specific outcomes in patients who are taught stress management techniques. Furthermore, researchers continue to identify chronic stress as a causative factor in numerous pathophysiologic processes that are known to be associated with the development, progression, and recurrence of various cancers (eg, stimulation of systemic inflammation and oxidation, impairment of immune function, increases in insulin resistance and weight gain, etc).
Nonetheless, even in the face of compelling data, it is important for the supporters of the stress-and-cancer association (of whom I am one) to recognize that “correlation does not imply causation.” The one thing that all of us can say with confidence is that employing evidence-based stress-reducing approaches (mind-body therapies, lifestyle changes, etc) improves quality of life, and improving quality of life may lead to indirect improvements in cancer-specific outcomes (eg, through improving treatment tolerance).
In defense of proponents of unproven therapies, it may be a bit harsh and premature to assign them the “quackery” label. One can certainly make the case that studies have either not been conducted or were not designed appropriately to definitively assess efficacy in a specific setting. However, as they say, “absence of evidence is not evidence of absence.” Many alternative therapies, once believed by conventional medical practitioners to be merely placebos, have now been shown to have proven therapeutic value (eg, acupuncture, numerous botanical extracts, meditation).
To briefly touch on the topic of placebos, it is important to recognize that the placebo response to any therapy is not insignificant. As an example, for years, physicians have prescribed antidepressant medications to patients with a diagnosis of mild-to-moderate depression. A 2010 paper in JAMA reported that for most patients with this condition, taking a placebo was equally effective as taking an FDA-approved antidepressant (and without the side effects). Did this highly publicized analysis change the standard of practice for the management of mild-to-moderate depression? I doubt it. But would prescribing a depressed patient a substance known to the physician to be a placebo be an example of quackery? I leave this to your own interpretation.
Financial Disclosure: The author has no significant financial interest or other relationship with the manufacturers of any products or providers of any service mentioned in this article.
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