Choi, T.Y., Lee, M.S., Kim, T.H., Zaslawski, C., & Ernst, E. (2012). Acupuncture for the treatment of cancer pain: A systematic review of randomised clinical trials. Supportive Care in Cancer, 20, 1147–1158.

To perform a combined systematic review and meta-analysis to assess the effectiveness of acupuncture for treating cancer pain

• Databases searched were MEDLINE, Allied and Complementary Medicine Database (AMED), EMBASE, CINAHL, PsycINFO, the Cochrane Library 2011, Korean Studies Information, DBpia (a database of Korean publications), Korean Institute of Science and Technology Information, Research Information Centre for Health Database, KoreaMed, Korean National Assembly Library, Chinese Medical Database of the China Academic Journal, and China Doctor/Master’s Dissertations.  
• Search keywords were the English terms that follow and their Korean and Chinese equivalents: (acupuncture OR electro-acupuncture OR auricular acupuncture OR scalp acupuncture OR needle OR acupuncture point OR meridian OR acupoint OR acupuncture treatment OR acupuncture therapy) AND (cancer OR tumour OR neoplasm OR pain).
• Studies were included if
  • Acupuncture was used as the sole intervention or as an adjunct to another standard treatment for any cancer pain.
  • The control group received the same concomitant treatments as the acupuncture group.
  • They were controlled by means of a placebo or they controlled against a drug-therapy or no-treatment group.
• Studies were excluded if they were nonrandomized trials, were trials with designs that did not allow the effectiveness of acupuncture to be evaluated, adopted comparison treatments or groups that were expected to have effects similar to acupuncture or used herbal medicines, were trials that studied cancer pain mixed with other types of pain, were trials that were conducted on patients during or a few days after an operation on malignant tumors, or were trials in which outcome measures were irrelevant to cancer pain.

• The search retrieved 494 references published through April 2011.
• Two independent reviewers read all articles. Reviewers extracted data from the articles according to predefined criteria. Risk of bias was assessed using criteria from the Cochrane classification.
• Nine studies were included in the meta-analysis. Data were pooled for a meta-analysis by using a random-effects model.

• The final number of studies included was 15; all were randomized controlled trials (RCTs).
• Total sample size was 1,157.
• Fourteen studies were conducted in China; these studies included a total of 1,070 participants. One study was conducted in France; this study included 87 participants.
• Three RCTs contained cases of liver cancer, one RCT contained at least one case of stomach cancer, and one RCT contained at least one late-stage cancer. 
• The focus of the meta-analysis was traditional Chinese acupuncture.

The study has clinical applicability for palliative care.

Most of the studies involved manual acupuncture based on traditional Chinese medicine. In regard to effect on cancer pain, the majority of the studies found the effects of acupuncture and conventional drug therapy to be comparable; however, equivalence of effects is unclear in those studies reporting no differences between acupuncture and conventional drug therapies.

Acupuncture may be an effective intervention for controlling pain; however, due to the small number of RCTs, low methodological quality, and small sample sizes, the results of the meta-analysis did not provide strong evidence of such effectiveness.

• All the RCTs had a high risk of bias.
• Because all the research evaluated was published in China, authors were uncertain of the accuracy of the findings.

Further research is needed to evaluate this nonpharmacologic intervention for relieving cancer pain.