Of all the types of cancer we treat with radiation, head and neck cancer has by far the worst side effects. Head and neck cancer comes in many different forms, but one thing those tumors have in common is that they are usually very close to radiation sensitive structures like the parotid glands (which produce saliva), the esophagus and the spinal cord. Spinal cord tolerance is never exceeded in a curative case because the consequences, total paralysis or death, are too dire. However, overdosing the parotid glands is not life threatening. The end result is xerostomia, or an inability to produce saliva. Since the parotid gland tolerance to radiation is very low, giving a low enough dose to spare the parotid would often result in a greatly reduced chance of killing the tumor. Therefore, it is often the case in the course of therapy that the parotid gland on at least one side is rendered unable to function.
While not life threatening, xerostomia still has a large negative effect on a patient’s quality of life. The American Dental Association gives some of the problems a patient might face.
Some of the common problems associated with dry mouth include a constant sore throat, burning sensation, problems speaking, difficulty swallowing, hoarseness or dry nasal passages. Left untreated, dry mouth can damage your teeth. Without adequate saliva to lubricate your mouth, wash away food, and neutralize the acids produced by plaque, extensive decay can occur.
While there is some indication that salivary function may eventually recover, for most patients there is no cure; only symptom management. Anything that could help relieve these symptoms would make a profound difference in these patients’ quality of life. So it probably shouldn’t be a surprise that some groups are using acupuncture to attempt to stimulate the flow of saliva.
Many studies have looked at the effect of acupuncture on various maladies. Some small scale studies have shown a positive effect. However, when follow-up studies are performed, again and again the results are found to be consistent with the placebo effect. Things are no different in this case.
Nineteen patients were given acupuncture following radiation therapy to the head and neck. Over the next 8 weeks, their salivary flow was measured and they were given questionnaires to assess their quality of life. The responses to the questionnaires indicated that quality of life had improved; the patient’s scores going from 40% to 55.6% over the 8 weeks (a higher percentage is better). However, measurements of their salivary flow indicated no statistically significant increase. The explanation:
The researchers also note that basal and salivary flow rates vary significantly among individuals, and therefore, subjective perceptions and objective measurements do not always correlate. A definitive threshold of increased saliva output that results in a clear clinical benefit has not been established, so even a small increase can provide relief to the patient.
That seems like a convoluted conclusion. The simpler conclusion would be that acupuncture did not actually cause any physiological effect, but caused the patient to believe that it would help. This is the very definition of the placebo effect. The authors even admit to this (at least somewhat).
It is also possible that the results could be attributed to a placebo effect, at least in some patients. However, the researchers do note that patients who have had major salivary glands irradiated do not spontaneously improve after 4 months, so the improvements in this trial “were most likely attributable to the acupuncture treatment rather than spontaneous recovery.”
So, who cares? Patients feel better. Even if it’s just a placebo, if it helps them out what’s the harm? There’s no real harm to the patients, aside from being unnecessarily stuck with needles. The harm comes from the diversion of resources from treatments that have a chance of leading to something better. This research was apparently funded by a grant from the National Cancer Institute. It probably was a cheap study to run, so the loss of NCI resources was not too great. However, ask anyone who depends on government funding to perform medical research; there is not enough to go around. Why continue to spend money on something that has been shown time and time again not to work?
I sympathize with the desire to try anything to help these people out, but too many promising research avenues have been cut short from lack of funding. If a private foundation wants to sponsor research into acupuncture, that’s fine. It’s possible that some positive physiological effect will eventually be found. Government money is hard to come by, though, and should be given to projects with a better chance of success.
