of Coriolus versicolor
Physical Characteristics of Coriolus versicolor
Published in Japan since the 1970s, over 400 clinical studies
have shown that a purified extract derived from the mushroom,
Coriolus versicolor, offers strong benefits for the immune system.
The extract is a protein-bound polysaccharide preparation isolated
from the mushroom's mycelia and fruit bodies by use of hot water
in a multi-step procedure. After completion of the extraction
process, the evolved solution is concentrated and dehydrated.
The brownish mushroom powder remaining is encapsulated for easy
ingestion. Taken either alone or with conventional chemotherapy
or radiotherapy for cancer, three or more grams per day of this
brown-powdered extract, administered orally, results in antitumor
activity. In vivo studies of rats and mice show that Coriolus
polysaccharides work well against a variety of experimental animal
cancers such as sarcoma, hepatoma, and fibrosarcoma.
Coriolus versicolor goes by a number of botanical names, including
Trametes versicolor, Boletus versicolor, Polyporus versicolor,
Polystictus versicolor, and the common idiomatic attribution of
“turkey tail.” The fruiting bodies do resemble a turkey tail in
full plumage and the versicolor name comes from this mushroom
being variously colored. In Japan it's called “kawaratake,” which
means mushroom by the river bank. Among the common people in China,
the fungus is referred to as “yun-zhi,” indicating that it's a
cloud fungus and grows best in the rain.
As an often seen denizen of the woods populating the temperate
zones of North America, Asia, and Europe, Coriolus versicolor
possesses fan-shaped fruiting bodies which grow in overlapping
clusters on dead trees. The mushroom's top portion is zoned, usually
in shades of brown, white, grey, or blue, and it sports hairy
bands. The underside of its cap is white and shows minute pores
which do not discolor after scratching.
The Active Medicinal Components
The mushroom's active medicinal components-biological response
modifiers which are protein-bound polysaccharides can be found
in both the fungus' fruiting body and its mycelium (the vegetative
stage). Although these concentrated polysaccharide extracts are
sold under a variety of trade names in North America and Asia,
they are most commonly referred to by the Japanese language designated,
water-soluble “Polysaccharide Kureha” or Polysaccharide K (commonly
referred to as PSK by those informed patients using Coriolus versicolor).
PSK contains the main components of -1,4- and -1,6- glucans with
-1,3- and 1,6- linkages. Also the mushroom contains other medicinal
components of secondary importance.
All of these potent but safely used medicinal components are
reported as effective against stomach (gastric) cancer, uterine
cancer, colon cancer, and lung cancer.
As clinically and anecdotally reported below, the mushroom
extract additionally works well against colorectal cancer, prostate
cancer, breast cancer, and liver cancer.
PSK Acts Alone Against Colorectal Cancer
Publishing in Cancer Immunology and Immunotherapy,
no less than 11 oncological researchers representing six prestigious
medical schools in Japan conducted a randomized double-blind trial
on 111 patients who had colorectal cancer. After they had undergone
surgical operations for their cancers, 56 patients were given
PSK alone as an active treatment substance, and 55 other post
surgical patients merely received a placebo.
Comparing the two groups, these eleven medical researchers advised,
“There is significant prolongation of disease-free periods for
patients with colorectal cancer who took PSK. Additionally. polymorphonuclear
leukocytes from patients treated with Coriolus versicolor showed
remarkable enhancement in their activities, such as random and/or
chemotactic locomotion, and phagocytosis.
In conclusion, PSK was useful as a maintenance therapy for patients
after their curative surgical operations for colorectal cancer.
The beneficial effects were probably due to the activation of
leukocyte functions as one of the many biological-response-modifying
activities induced by PSK.
Kenneth Bock, MD Observes PSK Boosts NK Cells
“Because it increases natural killer [NK] cell activity, I think
of using Coriolus versicolor mainly when I'm confronted with a
patient suffering from cancer or a viral infection,” says Kenneth
A. Bock, MD, medical director of two wholistic medical clinics,
one located in Rhinebeck, New York and the other in Albany, New
York. “This mushroom is one of the main medicinal compounds I
use to boost a diminished blood reading which records NK activity.
PSK does produce a marked improvement in NK cell function and
number, something I monitor by testing. If the blood reading is
low, my patient takes greater amounts of PSK capsules. And, although
it's an expensive and sophisticated assay, I repeat my NK cell
testing inside of a month or two. In a number of patients, I've
seen some nice blood test improvements.
“Before consulting me, a few patients with advanced metastatic
cancer show NK cell activities of only 2 or 3 minute units (m/u).
Normal measurements for the laboratory I employ is between 20
and 50 m/u. By using PSK for most of these patients, I have observed
their NK cells increasing into the normal range. They then experience
an improved prognosis,” says Dr. Bock. “I can illustrate what
I'm saying by providing a before-and-after patient case history
plus the literature that backs my claim.
“Here is a white, married male with the initials M.E., 60 years
old, working as a computer consultant, who originally had been
followed medically for hypertension, hyperlipidemia, and arteriosclerosis,
during 1995. He also exhibited laryngeal polyps which were cancerous.
M.E. received radiation therapy as a followup to the surgery performed
to remove these polyps,” points out Dr. Bock. “At the time of
surgery, a CT scan to his pelvis was negative for cancer metastasis
to the prostate. But later, in April 1997, M.E. did show an elevated
PSA [prostate-specific antigen] and underwent an additional medical
workup, including biopsy. Workup results indicated his true diagnosis,
which was prostate cancer. His blood test showed diminished natural
killer cell activity at the level of 6 m/u. Still, M.E. wanted
no conventional therapy for the prostate cancer,” Dr. Bock tells
me. “So I started him on alternative medical therapies for prostate
cancer and to improve his deficient NK cell activity. Coriolus
versicolor was a definite part of M.E.'s treatment regimen. “Within
two months, the patient's NK cell activity elevated to 18 m/u.
And two months after that his NK cell activity increased to a
normal 31 m/u. Now M.E. is doing well physically, and he tells
me he feels great! I would say that this type of response to PSK
therapy is usual; the patient's quality of life does improve dramatically
and he or she feels a sense of wellbeing,” Dr. Bock states.
Kenneth A. Bock, MD, lectures extensively to health professionals
and consumer groups on wholistic medicine. Engaged in family practice,
Dr. Bock specializes in treating patients for allergies; plus,
he treats heart and blood vessel diseases for which he employs
chelation therapy, nutritional therapies, and preventive medicine.
Animal Studies of Coriolus versicolor
Animal studies investigating the efficacy of Coriolus versicolor
indicate it has marked immune system-enhancing activity and a
broad antineoplastic scope. It prolongs the survival time of irradiated
(cancer-induced) mice by stimulating phagocytic activity of macrophages
and improving the functions of the reticuloendothelial system.
For another rodent-type of disease, cyclophosphamide-induced granulocytopenia
in mice, PSK caused a significant increase in granulocyte production.
Also it restored antibody (IgG) production in mice bearing sarcoma
180, but not in normal mice.
PSK acts directly against tumor cells as well as indirectly in
the host to boost cellular immunity. The following is a listing
of cancers for which it is known to be efficacious in animals:
adenosarcoma, fibrosarcoma, mastocytoma, plasmacytoma, melanoma,
sarcoma, carcinoma, mammary cancer, colon cancer, and lung cancer.
Indeed, injection of the PSK compound at one tumor site shows
tumor growth inhibition at other sites, thus helping to prevent
metastasis. Moreover, its antitumor activity increases when PSK
is administered in combination with radiation, chemotherapy, or
immunotherapy. Giving the polysaccharide substance in 10% or less
of rat feeds does suppress carcinogen-induced rodent cancers of
the colon, esophagus, breast, and lung.
PSK demonstrates antiviral activity and may be effective against
the human immunodeficiency virus (HIV) infection by modifying
the viral receptor or by stopping it from binding with lymphocytes.
Another mechanism through which PSK shows general antiviral activity
is through the stimulation of interferon production.
Whole Coriolus versicolor lowers serum cholesterol in animals.
In combination with the herb Astragalus membranaceus Bunge, it
enhances neutrophil function and speeds recovery in rabbits suffering
from burns. A powdered extract of PSK from the 70% ethanol tincture
of this species tested in rats by injection in a Hippocratic screening
of higher fungi did demonstrate mild tranquilizing and diuretic
PSK is Supportive of Chemotherapy/Radiotherapy
Providing strong benefits for the immune system when given
alone, Coriolus versicolor works even more supportively against
cancer after it's applied with chemotherapy and/or radiotherapy.
In fact, out of 200 adjunctive phytochemicals screened for antitumor
activity by Japanese researchers in 1971, PSK was selected as
the best adjunctive treatment.
The researchers suggested that this medicinal mushroom seemed
to protect the immune system's activity from being suppressed
by the chemotherapy drugs and by the toxic processes of the cancer
itself. Added to that finding, a ten year study of 185 patients
with lung cancer showed that combining PSK with radiation therapy
produced “satisfactory” tumor shrinkage and better survival rates
for patients with stage I cancer (39%) and stage II cancer (22%)
compared against those patients with stage I cancer (16%) and
stage II cancer (5%) who did not receive this combination of therapies.
Reporting the above study in another more exacting way: From
1976 to 1985, 185 patients with non-small cell lung cancer at
stages I, II, and III were treated with definitive radiotherapy
in Gunma University Hospital at the Gunma University School of
Medicine in Maebashi, Japan. The long term survivors were analyzed
carefully. Those who had received Coriolus versicolor as adjunctive
treatment showed more satisfactory tumor shrinkage and their five
year survival rate was better than those patients not receiving
PSK. That is, PSK patients with stages I or II disease showed
up with 39% survival; PSK patients with stage III cancer had 22%
survival. Comparing these survivors with the stage I and stage
II non-PSK group, we see that these non-PSK patients had only
16% and 5% survival, respectively. The non-PSK stage III patients
had no survivors.
In Japan, the standard adjunctive treatment after resection of
gastric cancer is a combination of two cytotoxic drugs, intravenous
mitomycin plus oral fluorouracil. As a clinical test, the protein-bound
polysaccharide PSK was added to this standard chemotherapy for
262 randomly assigned patients. Half received Coriolus versicolor
and half took the usual chemotherapy alone after all of them had
undergone what the Japanese label as “curative” gastrectomy. During
a minimum followup of five years (ranging from five to seven years),
the clinical testing took place at 46 institutions in central
PSK improved the cancer patients' five-year, disease-free rate
at 70.7% versus 59.4% in a standard treatment group (p=0.047).
And it improved their five-year survival rate at 73.0% versus
60.0%, (p=0.044) as well. The two regimens had only slight toxic
effects, consisting of nausea, leucopenia, and liver function
impairment. There were no significant differences between the
groups. The treatments were clinically well tolerated and compliance
of patients was good. In their paper published in Lancet, the
researchers concluded, “Addition of PSK to adjunctive chemotherapy
with mitomycin and fluorouracil is beneficial as treatment after
Between January 1980 and December 1990, 227 operable breast cancer
patients with vascular invasion in their tumors and/or in their
metastatic lymph nodes were randomized into three treatment groups.
Group one received a combination of toxic therapies, what the
researchers labeled as “FEMP” (5-fluorouracil, cyclophosphamid,
mitomycin C, and predonisone). Group two received FEMP plus LMS
(levamisole). Group three received FEMP plus PSK.
The seven Japanese researchers concluded: “Immunochemotherapy
using PSK improved the prognosis of patients having operable breast
cancer with vascular invasion..The prognosis of the FEMP + PSK
group tended to be better than that of the FEMP group. FEMP +
PSK is better because of its usefulness including good compliance.
Twenty-eight patients suffering from acute leukemia who had achieved
complete remission participated in a clinical trial. Starting
in September 1976, half of these patients entering the chemo-PSK
immunotherapy group received the medicinal mushroom, Coriolus
versicolor, and half entering the strictly chemotherapy group
did not. To retain the patients' remission, all of them received
three courses of the chemotherapy combination of cytoxics consisting
of 40 units/kg/day of neocarzinostatin; 0.8 -1.6 mg/kg/day of
cytosine arabinoside; 0.6 - 0.8 mg/ kg/day of daunorubicin; and
0.8 -1.6 mg/kg/day of prednisolone on days one to four for acute
non-lymphocytic leukemia, and 0.04 mg/kg/day of vincristine on
day one: 0.6 - 0.8 mg/kg/day of daunorubicin; and 0.8 - 1.6 mg/kg/day
of prednisolone on days one to four for acute Lymphocytic leukemia.
The durations of complete remission and survival in the chemo-PSK
immunotherapy group (receiving PSK) showed significant prolongation
compared to that of the Strictly chemotherapy group (not receiving
PSK). The median duration of complete remission for this PSK group
was thirty-six weeks and that for the non-PSK group was twenty-five
weeks. The average survival time from diagnosis of the PSK group
was twenty-one months and that of the non-PSK group was twelve
Tori Hudson, ND, Uses Coriolus versicolor
“The only condition I've been using Coriolus versicolor for is
breast cancer, stage II and above, in which the patients have
been actively receiving chemotherapy. If they are just starting
their chemotherapy, I've added PSK. When the patients are finished
with their chemotherapy I've continued the PSK. This procedure
is followed in accordance with my understanding of the few research
articles I've read relative to breast cancer patients and PSK.
My intention is to keep the breast cancer patient taking Coriolus
versicolor for a total of five years. But I've been using the
mushroom for only a year now,” says naturopathic physician Tori
Dr. Tori Hudson, whom all of us recognize as a columnist for
the Townsend Letter for Doctors & Patients, is a professor
teaching at the National College of Naturopathic Medicine in Portland.
She is health care director at her Portland, Oregon clinic which
operates under the name: “A Woman's Time.” “I have just begun
using PSK for a man who is facing the recurrence of gastric cancer.
He's had a full gamut of therapies and still shows elevated cancer
markers which his oncologist finds untreatable. The patient was
referred to me for some alternative cancer therapy because conventional
oncology has nothing more to use on him,” says Dr. Hudson. “My
impression is that patients taking Coriolus versicolor are experiencing
less side effects from chemotherapy such as diminished fatigue,
less nausea, (but not less hair loss), and more stable white blood
cell counts. I have not measured the natural killer cell counts.”
A Patient's Experience with Liver Cancer Reduction
A 64 year-old electrical engineer in Tyler, Texas. Allen Greenstaff
had been doctoring with liver cancer for six years. In the beginning
stages of his malignancy, he took chemotherapy which eventually
proved to do no good. And the oncologist offered him absolutely
nothing more as treatment, not even personal care to accomplish
a better quality of life for himself - no improved diet, nutrients,
exercise, meditation - just nothing at all.
“That doctor was the most negative man I ever met,” said Mr.
Greenstaff. “After the chemo failed, he threw up his hands, shrugged
his shoulders, wished me good luck, and said there was nothing
else he could do. And surgery couldn't be performed either, because
the consulting surgeon saw that the tumor was wrapped around my
vena cava blood vessel.”
The patient replied to his oncologist, “I totally reject what
you are telling me. I do not accept that nothing can be done to
affect the outcome of this disease.” When the doctor said, “Well,
I know what I'm talking about when it comes to cancer. I'm a scientist,”
Allen Greenstaff shot back, “Yes, but you're not God!”
Even with being abandoned by his oncologist, today the patient
is healthy once again after utilizing alternative methods of healing,
most especially by his self-administration of oral Coriolus versicolor.
Mr. Greenstaff's tumor, which had been situated on the left lobe
of the liver, was sized at 10 cm by 7 cm and by the longitudinal
measurement of 9 cm. Now, after he has been taking capsules of
PSK, the tumor has shrunk to 6 cm by 4 cm by 3 cm (longitudinally).
The patient had learned about Coriolus versicolor from his contacting
Medline on the internet. By digging into the world wide web, he
has saved himself. Remarkably, the volume of Mr. Greenstaff's
liver cancer has reduced to less than 10% of its original size,
from 630 cm down to 60 cm. And his carcinoembryonic antigen (CEA)
cancer marker has improved dramatically as well, dropping from
296 to 97.9.
Today, after two years, Mr. Greenstaff still swallows those usual,
brownish colored mushroom capsules, which he intends to take the
rest of his life. He is well-versed in the efficacy of Coriolus
versicolor, since the man has read nearly 400 studies about PSK
that he printed out from the internet.