Reference
Eliza WL, Fai CK, Chung LP. Efficacy of Yun Zhi (Coriolus versicolor) on survival in cancer patients: systematic review and meta-analysis. Recent Pat Inflamm Allergy Drug Discov. 2012;6(1):78-87.
Note
Yun Zhi is also known as Coriolus versicolor, Trametes versicolor, and Polyporus versicolor. Most current cancer research in the United States refers to it as Trametes versicolor.
Design
Out of 110 potential relevant trials using Coriolus versicolor in medical literature from 1973 to 2003, the field was narrowed to 55, and 13 were selected after meeting the inclusion criteria for statistical pooling. Studies selected (ranging from 1988 to 1998) were randomized, placebo-controlled, and double-blinded and included survival data. All compared Coriolus versicolor or its extract (PSP or PSK) with conventional anticancer treatments. The dosage range was 1–3.6 g/day. Duration of therapy was 1 to 36 months. Cancer types included were esophageal cancer, gastric cancer, colon/rectal cancer, breast cancer, and nasopharyngeal carcinoma in stages I to IV. Meta-analysis was used to analyze efficacy of Coriolus versicolor along with conventional cancer therapy vs conventional cancer therapy alone.
Key Findings
Patients randomized to Coriolus versicolor had a 9% absolute reduction in 5-year mortality, which means that for every 11 treated, 1 additional patient lived. These findings were most prominent in patients treated with chemotherapy for breast, colorectal, and gastric cancers. All of the patients with the above types of cancer were receiving chemotherapy, so it was difficult to predict if type of cancer or type of conventional treatment (esophageal and nasopharyngeal cancer patients were receiving radiotherapy) made the difference in outcome.
In all 13 trials, the addition of Coriolus versicolor therapy did not result in an increase in adverse effects. And surprisingly, 5-year survival was not associated with length of treatment with Coriolus versicolor therapy.
Discussion
Coriolus versicolor is the most well-studied medicinal mushroom in the world. For the purposes of this article we will look only at human studies, but the potential for this mushroom to aid in improving human health is seen in many in vitro and animal studies.
A chemical engineer in Japan isolated PSK in 1965, inspired by a case of cancer remission after ingestion of the extract.1 It was adopted into the national healthcare system there in 1977. Currently it accounts for 25% of the total cancer therapy costs in Japan, where it is covered by insurance. PSP, another polysaccharide complex, was isolated in China in 1983 and has been well studied in cancer therapies since. In cases of colorectal cancer, 5 clinical trials have been published since 2005 that show the benefits of using PSK, including 1 meta-analysis that included 1,094 patients.2
Several studies show promise using Coriolus versicolor in treating cervical lesions. One study conducted in 2007 by Dr. Silva Couto showed not only improvement of the normalization of cervical cytology but also reversal of the patients’ HPV+ status to negative.3
Researchers published a study in 2011 showing that PSK can increase the effectiveness of monoclonal antibody therapy in breast cancer patients.4 Data from epidemiological and clinical studies on Coriolus versicolor used as adjuvant therapy show that its use in breast cancer therapy is warranted and demonstrated its usefulness as a secondary preventative strategy. This is largely based on the science showing that these polysaccharide extracts increase NK cells, alter cytokine production with a shift toward T-helper 1 immunity, and increase some lymphocyte populations while also decreasing T regularly cells. This shift toward cytotoxic immunity is believed to be the foundation of the anticancer effects.5
The specific process used in extracting the mushroom polysaccharide is important. Hot water extraction is the gold standard for the medicinal use of Coriolus versicolor. Some recent studies have utilized the cultivated biomass, but this is much less common and though the process is less expensive, it yields lower levels of the active polysaccharides.
Clinical Implications
The many studies are quite clear: While there is not enough evidence to support using Coriolus versicolor alone for cancer treatment, there are mountains of evidence showing its efficacy as an adjuvant therapy. Particularly in cases of breast cancer, colorectal cancer, and gastric cancer, this mushroom therapy should be a component of the treatment plan, both during and after conventional treatments.
For more research involving integrative oncology, click here.
