The patients were given either active acupuncture or a sham treatment that involved an identical looking and feeling needle that retracted into the handle on contact with the skin.
"Both groups of patients reported they believed the treatment had been invasive and effective in reducing nausea. However, 68 percent of patients who got the acupuncture experienced nausea for an average of 19 days during radiotherapy and 61 percent of the patients who got the sham treatment suffered nausea for an average of 17 days," said the study's lead researcher Anna Enblom, a physiotherapist and doctoral student at the Faculty of Health Sciences, Linköping University in Sweden.
"Vomiting was experienced by 24 percent of the patients getting acupuncture and 28 percent of patients receiving the sham treatment," Enblom added. Fifty-eight of the patients received chemotherapy in combination with radiotherapy. Among them, 82 percent of those in the acupuncture group developed nausea, compared with 80 percent of those treated with the sham needles.
"There was no statistically significant difference between the groups in the number of days with nausea or vomiting or in the intensity of the nausea, neither in the patients receiving radiotherapy alone, nor in those receiving a combination of chemotherapy and radiotherapy," said Enblom.
"Our study may indicate that attitudes and expectations play a major role in the experience of the effect of the treatment," she added. Acupuncture is increasingly used in cancer care as an alternative to drugs to treat therapy side effects such as pain and nausea, despite unclear evidence that it has any real effect. The percentage of cancer patients using acupuncture for various kinds of symptoms, including nausea and pain, varies from two percent to 30 percent depending on the population.
It is believed that acupuncture works by stimulating the peripheral circulation and activating nerves that prompt the release of important substances from the brain such as endorphins. "It has proven efficacy in pain related to, for example, osteoarthritis, but the evidence for its effect in cancer patients is lacking," Enblom said.
"In this study, the question of whether invasive acupuncture is more effective than non-penetrating placebo needles for the reduction of radiotherapy-related nausea is answered," Enblom added.
In the study presented at ECCO, 66 percent of patients who got acupuncture and 71 percent who got the sham treatment said they would be highly interested in having acupuncture again if it turned out they needed another course of radiotherapy.
In Sweden, the cost of acupuncture is covered by the state healthcare system when given for indications where it is proven to work. As long as the best possible available drug treatment for nausea is given to cancer patients receiving radiotherapy, the patient may be satisfied with a gentle and pain free acupuncture treatment and believe it helps. It is not recommended to give acupuncture if it produces pain or harm.