Xu, L., Lao, L.X., Ge, A., Yu, S., Li, J., & Mansky, P.J. (2007). Chinese herbal medicine for cancer pain. Integrative Cancer Therapies, 6, 208–234.

To summarize and evaluate the state of clinical research on the use of Chinese herbal medicine in the treatment of cancer-related pain

The type of article is systematic review.

Databases searched were Chinese Biomedical Literature, Chinese Medical Current Content, Wanfang, and Weipu databases in Chinese, and PubMed and EMBASE in English.

Search keywords were Chinese herb, Chinese medicine and neoplasms and pain. Specific search terms in English and Chinese are displayed in this report.

Studies were included in the review if they were reports of original work on cancer-related pain.

Reviews, commentary, abstracts, and reports on pain associated with cancer therapies were excluded.

An initial search provided 212 Chinese articles and 161 articles from English literature.

Study quality was evaluated using the National Cancer Institute’s Levels of Evidence for Human Studies of Cancer Complementary and Alternative Medicine guidelines.

• A final sample of 115 articles, 106 of which were retrieved from Chinese databases, was included in the report.
• Studies included 3,878 patients. Study sample sizes reported ranged from to 46 to 250 patients.

Results are organized according to route of administration: oral, IV, and other methods of application, such as inhalation.

Treatment Outcomes

External application: This is the most common use. This area included 41 studies

• Analgesic effect was equivalent to positive control treatment across studies.
• In numerous studies, the comparison positive control was nonsteroidal anti-inflammatory drugs (NSAIDs) or palliative chemotherapy or radiation therapy. Few studies were in comparison to opioids.

Oral administration: 48 studies were in this category. Comparison positive controls in this group tended to also be palliative chemotherapy or radiation therapy, NSAIDs, and opioids. Dosage ranges of comparison medications were not discussed.

IV infusions: 23 studies were reported; however, authors included studies of intramuscular administration, and samples being actively treated with chemotherapy or radiotherapy for pain. Overall positive results compared to placebo or no active controls were reported.

Other administration methods: One study involving inhalation and one involving per rectum administration are discussed. 

Adverse Reactions: Adverse events were slight and brief, and in most cases patients did not require further intervention. Adverse effects were reported to be higher in conventional medicine control groups.

The authors conclude that Chinese herbal medicine may be useful for managing cancer pain. However, there is no discussion of the fact that control comparisons used were no specific pain treatment, or low-level interventions such as NSAIDs. In this regard, controls used in the research summarized here were insufficient to provide realistic scientific comparisons. Methods of pain measurement reported here show mostly use of a single pain measure such as various verbal reporting scales, which can be expected to influence reliability and validity of individual study results. The authors point out that the quality of studies, design and methods, and study reporting was low. The authors suggest specific approaches in study design for improvement of research in this area.

Well-designed research in the use of Chinese herbal medicine is needed to enable firm conclusions about efficacy. Research regarding the role of this type of treatment as adjunctive pain management would also be useful. Findings here provide only minimal support for the use of Chinese herbal medicine to effectively manage cancer-related pain.