A combined analysis of 34 studies suggests that Astragalus-based Chinese herbal medicine may increase the effectiveness of platinum-based chemotherapy regimens for advanced non-small cell lung cancer (NSCLC). (However, because the quality of several of the evaluated studies was poor, these findings need to be confirmed in well-designed clinical trials.) These results were published in the Journal of Clinical Oncology.

Lung cancer remains the leading cause of cancer deaths in the U.S. and Europe. Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for approximately 75%–80% of all lung cancers.

Advanced NSCLC refers to cancer that has spread from its site of origin to distant and/or several sites in the body. Chemotherapy regimens that include a platinum-based drug such as carboplatin are often used in the treatment of advanced NSCLC, but frequently cause significant side effects. Furthermore, even with treatment, survival among patients with advanced NSCLC continues to be poor. Researchers therefore continue to evaluate new treatments and new combinations of treatments.

In China, the herb Astragalus membranaceus is frequently combined with chemotherapy in the treatment of lung cancer. It is thought that Astragalus may play a role in stimulating the immune system.

To summarize what is known about the combination of Astragalus-based Chinese medicine and standard platinum-based chemotherapy for NSCLC, researchers combined information from 34 published clinical trials. These trials enrolled a total of 2815 patients. The researchers assessed whether Astragalus-based herbal medicine increased the effectiveness and decreased the toxicity of standard platinum-based chemotherapy.

• At 12 months, risk of death was reduced by 33% among patients treated with Astragalus-based herbal medicine and chemotherapy, compared to patients treated with chemotherapy alone.
• Tumor response to treatment was increased by 34% among patients treated with Astragalus-based herbal medicine and chemotherapy.
• Patients treated with Astragalus-based herbal medicine and chemotherapy were more likely to experience a stable or improved level of functioning.

While these findings suggest a potential benefit of Astragalus-based Chinese herbal medicine, the researchers caution that several of the evaluated studies were of low quality. Quality was assessed on the basis of whether the study was described as randomized, whether the method of randomization was reported, whether patients and physicians were blinded to the patient’s treatment status, and whether the researchers accounted for patients who dropped out of the study. On a scale of 0 to 5, with 5 being the best, only three studies were given a score of 2 or higher. The quality of the remaining studies was rated as 0 or 1.

The researchers conclude that “Astragalus-based Chinese herbal medicine may increase effectiveness (by improving survival, tumor response, and performance status) and reduce toxicity of standard platinum-based chemotherapy for advanced non-small-cell lung cancer.” They also note, however, that “confirmation of these conclusions in rigorously controlled, randomized trials is required before more firm conclusions about this therapy can be drawn.”

Reference: McCulloch M, See C, Shu X-j et al. Astragalus-Based Chinese Herbs and Platinum-Based Chemotherapy for Advanced Non-Small-Cell Lung Cancer: Meta-Analysis of Randomized Trials. Journal of Clinical Oncology. 2006;24:419-430.