Prognostic proof and possible therapeutic mechanisms of herbal medicine in patients with metastatic lung and colon cancer.

Recent studies based on epidemiological models published in this journal and elsewhere have demonstrated encouraging patterns suggesting that herbal treatment may improve prognosis in advanced colon and lung cancer patients. Various problems exist with data from nonrandomized studies of this type, but a strong signal of potential positive effect can be seen. The therapeutic mechanisms of traditional Chinese medicine in metastatic cancer are discussed against a hypothetical, dualistic antiproliferation model and immune-stimulation model of tumor progression and regression. Recommendations are made for a strategy to demonstrate more conclusively the efficacy of adjunct herbal treatment during cancer chemotherapy and for discussions with patients until such time as the efficacy trials are completed.