Health Care Professional Information
Common Name
Forest mushroom, lentinula, pasania fungus, lentinula, hua gu
Clinical Summary
Shiitake mushroom, native to East Asia, is cultivated worldwide for its purported health benefits. The fresh and dried forms of the mushroom are commonly used in East Asian cooking. It is also valued as an anticancer agent.
Lentinan (1,3 beta-D-glucan), a polysaccharide isolated from Shiitake, has been well studied and is thought responsible for Shiitake's beneficial effects. It was shown to have anticancer effects in colon cancer cells (1), which may be due to its ability to suppress cytochrome P450 1A enzymes that are known to metabolize pro-carcinogens to active forms (2).
Lentin, the protein component, has strong antifungal properties, inhibits proliferation of leukemic cells, and suppresses the activity of human immunodeficiency virus-1 reverse transcriptase (3). Studies conducted with Shiitake extracts in vitro and in mice revealed the mushroom's antiproliferative (4), cytotoxic (21), immunostimulatory (4), hepatoprotective (5), antimutagenic (6), and anticaries (7) properties, but a clinical trial failed to show effectiveness in the treatment of prostate cancer (8).
Results from two small studies of HIV-positive patients who were administered intravenous lentinan showed a statistically insignificant increase in CD4 cells and neutrophil activity in some patients; researchers also reported severe adverse effects in some patients (9).
But improvements in quality of life and survival were seen with an oral formulation of superfine dispersed lentinan in patients with hepatocellular carcinoma (15), gastric (16), colorectal (17), and pancreatic (18) cancers. An orally administered Shiitake mycelial extract decreased the incidence of adverse effects associated with chemotherapy in a small study of patients with advanced gastrointestinal cancer (22).
Large scale studies are needed to establish Shiitake as a useful adjunct to cancer treatment.
Food Sources
Available as fresh or dried whole mushroom.
Purported Uses
- Cancer prevention
- Cancer treatment
- High cholesterol
- Immunostimulation
- Infections
Constituents
- Polysaccharides: Lentinan, 1-3-beta-D-glucan
- Protein: Lentin
- Lipids: Linoleic Acid
- Ergosterol
- Amino Acids: Lysine, arginine, methionine and phenylalanine
- Minerals and electrolytes: Potassium, calcium, magnesium, manganese, iron, copper, and zinc
- Lignins
(3)
Mechanism of Action
Lentinan possesses immune-regulatory, antimicrobial, anti viral, and cholesterol-lowering effects (13). The water extract of shiitake decreased IL-1 production and apoptosis in human neutrophils. However, it increased apoptosis in U937 monocytic cell line (14). Lentin, the protein component of shiitake, has strong antifungal effects. An in vitro study has shown lentin can inhibit the proliferation of leukemia cells and suppress the activity of human immunodeficiency virus-1 reverse transcriptase (3).
Adverse Reactions
Case Reports:
Chronic hypersensitivity pneumonitis was observed in a lung cancer patient following exposure to Shiitake spores (10).
Prolonged consumption of Shiitake powder resulted in dermatitis, photosensitivity (11), eosinophilia, and gastrointestinal upset (12).
Intermittent skin eruptions (dermatitis), over a period of 16 years, were linked to consumption of shiitake mushrooms in a 45-year-old male (19).
Food allergy manifested as oesophageal symptoms was reported in a 37-year-old man following consumption of shiitake mushroom (20).
Hypersensitivity pneumonia was reported in a 37-year-old man following inhalation of Shiitake mushroom spores (23).
Literature Summary and Critique
Few significant clinical studies have been performed with the shiitake mushroom. However, lentinan, a polysaccharide component of the mushroom, has been studied extensively.
Dosage (Inside MSKCC Only)
This field is only visible to only Inside MSKCC users.
References
- Ng ML, Yap AT. Inhibition of human colon carcinoma development by lentinan from shiitake mushrooms (Lentinus edodes). J Altern Complement Med 2002;8(5):581-589.
- Okamoto T, Kodoi R, Nonaka Y, et al. Lentinan from shiitake mushroom (Lentinus edodes) suppresses expression of cytochrome P450 1A subfamily in the mouse liver. Biofactors. 2004;21(1-4):407-409.
- Ngai PH, Ng TB. Lentin, a novel and potent antifungal protein from shitake mushroom with inhibitory effects on activity of human immunodeficiency virus-1 reverse transcriptase and proliferation of leukemia cells. Life Sci. Nov 14 2003;73(26):3363-3374.
- Israilides C, Kletsas D, Arapoglou D, et al. In vitro cytostatic and immunomodulatory properties of the medicinal mushroom Lentinula edodes. Phytomedicine 2008.
- Akamatsu S, Watanabe A, Tamesada M, et al. Hepatoprotective effect of extracts from Lentinus edodes mycelia on dimethylnitrosamine-induced liver injury. Biol Pharm Bull. 2004;27(12):1957-1960.
- de Lima PL, Delmanto RD, Sugui MM, et al. Letinula edodes (Berk.) Pegler (Shiitake) modulates genotoxic and mutagenic effects induced by alkylating agents in vivo. Mutat Res. 2001;496(1-2):23-32.
- Shouji N, Takada K, Fukushima K, Hirasawa M. Anticaries effect of a component from shiitake (an edible mushroom). Caries Res 2000;34(1):94-98.
- deVere White RW, Hackman RM, Soares SE, Beckett LA, Sun B. Effects of a mushroom mycelium extract on the treatment of prostate cancer. Urology 2002;60(4):640-644.
- Gordon M, Bihari B, Goosby E, et al. A placebo-controlled trial of the immune modulator, lentinan, in HIV-positive patients: a phase I/II trial. J Med 1998;29(5-6):305-330.
- Suzuki K, Tanaka H, Sugawara H, et al. Chronic hypersensitivity pneumonitis induced by Shiitake mushroom spores associated with lung cancer. Intern Med 2001;40(11):1132-1135.
- Hanada K, Hashimoto I. Flagellate mushroom (Shiitake) dermatitis and photosensitivity. Dermatology. 1998;197(3):255-257.
- Levy AM, Kita H, Phillips SF, et al. Eosinophilia and gastrointestinal symptoms after ingestion of shiitake mushrooms. J Allergy Clin Immunol 1998;101(5):613-620.
- Hobbs C. Medicinal Mushrooms, 3rd ed. Loveland (CO): Interweave Press; 1996.
- Sia GM, Candish JK. Effects of shiitake (Lentinus edodes) extract on human neutrophils and the U937 monocytic cell line. Phytother Res 1999;13(2):133-7.
- Isoda N, Eguchi Y, Nukaya H, et al. Clinical efficacy of superfine dispersed lentinan (beta-1,3-glucan) in patients with hepatocellular carcinoma. Hepatogastroenterology. 2009 Mar-Apr;56(90):437-41.
- Oba K, Kobayashi M, Matsui T, Kodera Y, Sakamoto J. Individual patient based meta-analysis of lentinan for unresectable/recurrent gastric cancer. Anticancer Res. 2009 Jul;29(7):2739-45.
- Hazama S, Watanabe S, Ohashi M, et al. Efficacy of orally administered superfine dispersed lentinan (beta-1,3-glucan) for the treatment of advanced colorectal cancer. Anticancer Res. 2009 Jul;29(7):2611-7.
- Shimizu K, Watanabe S, Watanabe S, et al. Efficacy of oral administered superfine dispersed lentinan for advanced pancreatic cancer. Hepatogastroenterology. 2009 Jan-Feb;56(89):240-4.
- Garg S, Cockayne SE. Shiitake dermatitis diagnosed after 16 years! Arch Dermatol. 2008 Sep;144(9):1241-2.
- Goikoetxea MJ, Fernández-Benítez M, Sanz ML. Food allergy to Shiitake (Lentinus edodes) manifested as oesophageal symptoms in a patient with probable eosinophilic oesophagitis. Allergol Immunopathol (Madr). 2009 Nov-Dec;37(6):333-4.
- Yukawa H, Ishikawa S, Kawanishi T, Tamesada M, Tomi H. Direct cytotoxicity of Lentinula edodes mycelia extract on human hepatocellular carcinoma cell line. Biol Pharm Bull. 2012;35(7):1014-21.
- Okuno K, Uno K. Efficacy of orally administered Lentinula edodes mycelia extract for advanced gastrointestinal cancer patients undergoing cancer chemotherapy: a pilot study. Asian Pac J Cancer Prev. 2011;12(7):1671-4.
- Ampere A, Delhaes L, Soots J, Bart F, Wallaert B. Hypersensitivity pneumonitis induced by Shiitake mushroom spores. Med Mycol. 2012 Aug;50(6):654-7.
Consumer Information
How It Works
Bottom Line: Lentinan, a polysaccharide extracted from Shiitake, may help extend the survival of patients with some cancers when used with chemotherapy.
The medicinal properties of Shiitake mushroom are attributed to a polysaccharide (sugar molecule) named lentinan, on which extensive research has been done. Lentinan is a polysaccharide called a 1,3 beta glucan. In laboratory tests, lentinan does not kill cancer cells directly, but enhances a number of aspects of the immune system, which may aid in the slowing of tumor growth. Lentinan also kills viruses and microbes directly in laboratory studies. Most studies involving lentinan involve intravenous or intramuscular injections. It is uncertain whether ingestion of shiitake mushrooms provides similar effects. One clinical trial has shown shiitake extract alone is not an effective treatment for prostate cancer. More studies are needed.
Purported Uses
- To prevent and treat cancer
A Shiitake extract was found ineffective for the treatment of prostate cancer. But an oral formulation of Lentinan was shown effective in extending the survival in patients with stomach, colorectal, pancreatic cancers and hepatocellular carcinoma. Larger studies are needed to confirm this.
- To lower high cholesterol
Lentinan has a cholesterol-lowering effect in lab studies, but there is no proof from clinical trials that either lentinan or shiitake mushrooms can lower cholesterol in people.
- To stimulate the immune system
Lentinan stimulates the activity of certain immune cells in lab studies and in people. However, it is unclear if lentinan or shiitake are effective in treating diseases such as AIDS and cancer.
- To treat infections
No scientific evidence supports this use.
Research Evidence
Few clinical studies have been performed with shiitake mushrooms. However, lentinan, the active compound present in shiitake mushrooms, has been studied in cancer patients.
Side Effects
- Dermatitis (inflammation of the skin)
- Increased skin sensitivity to sunlight
- Eosinophilia (an abnormally high level of certain white blood cells)
- Upset stomach
- Hypersensitivity Pneumonia
Special Point
- Shiitake mushrooms are a common part of the diet in many cultures. It is unknown what dose of lentinan is absorbed through the gastrointestinal tract when shiitake mushrooms are consumed.
Last updated: December 20, 2012
AIDS
A disease caused by the human immunodeficiency virus (HIV). People with AIDS are at an increased risk for developing certain cancers and for infections that usually occur only in individuals with a weak immune system. Also called acquired immunodeficiency syndrome.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)antifungal (AN-tee-FUN-gul)
A drug that treats infections caused by fungi.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)apoptosis (A-pop-TOH-sis)
A type of cell death in which a series of molecular steps in a cell leads to its death. This is the body’s normal way of getting rid of unneeded or abnormal cells. The process of apoptosis may be blocked in cancer cells. Also called programmed cell death.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)arginine (AR-jih-neen)
One of the twenty common amino acids (building blocks of proteins). Arginine is being studied as a nutritional supplement in the treatment and prevention of cancer and other conditions. Also called L-arginine.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)blood (blud)
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)calcium (KAL-see-um)
A mineral needed for healthy teeth, bones, and other body tissues. It is the most common mineral in the body. A deposit of calcium in body tissues, such as breast tissue, may be a sign of disease.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)cancer (KAN-ser)
A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord. Also called malignancy.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)carcinoma (KAR-sih-NOH-muh)
Cancer that begins in the skin or in tissues that line or cover internal organs.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)cell (sel)
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)cholesterol (koh-LES-teh-rol)
A waxy, fat-like substance made in the liver, and found in the blood and in all cells of the body. Cholesterol is important for good health and is needed for making cell walls, tissues, hormones, vitamin D, and bile acid. Cholesterol also comes from eating foods taken from animals such as egg yolks, meat, and whole-milk dairy products. Too much cholesterol in the blood may build up in blood vessel walls, block blood flow to tissues and organs, and increase the risk of developing heart disease and stroke.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)chronic (KRAH-nik)
A disease or condition that persists or progresses over a long period of time.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)clinical (KLIH-nih-kul)
Having to do with the examination and treatment of patients.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)clinical trial (KLIH-nih-kul TRY-ul)
A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)colorectal (KOH-loh-REK-tul)
Having to do with the colon or the rectum.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)compound (KOM-pownd)
In science, a substance that is made up of more than one ingredient.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)cytotoxic (SY-toh-TOK-sik)
Cell-killing.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)dermatitis (DER-muh-TY-tis)
Inflammation of the skin.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)diet (DY-et)
The things a person eats and drinks.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)dose (dose)
The amount of medicine taken, or radiation given, at one time.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)eosinophil (EE-oh-SIH-noh-FIL)
A type of immune cell that has granules (small particles) with enzymes that are released during infections, allergic reactions, and asthma. An eosinophil is a type of white blood cell and a type of granulocyte.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)eosinophilia (EE-oh-SIH-noh-FIH-lee-uh)
A condition in which the number of eosinophils (a type of white blood cell) in the blood is greatly increased. Eosinophilia is often a response to infection or allergens (substances that cause an allergic response).
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)extract (EK-strakt)
In medicine, a preparation of a substance obtained from plants, animals, or bacteria and used as a drug or in drugs.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)gastric (GAS-trik)
Having to do with the stomach.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)gastrointestinal (GAS-troh-in-TES-tih-nul)
Refers to the stomach and intestines. Also called GI.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)gastrointestinal tract (GAS-troh-in-TES-tih-nul trakt)
The stomach and intestines. The gastrointestinal tract is part of the digestive system, which also includes the salivary glands, mouth, esophagus, liver, pancreas, gallbladder, and rectum.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)hepatocellular carcinoma (heh-PA-toh-SEL-yoo-ler KAR-sih-NOH-muh)
A type of adenocarcinoma and the most common type of liver tumor.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)hypersensitivity (HY-per-SEN-sih-tih-vih-tee)
An exaggerated response by the immune system to a drug or other substance.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)IL-1
One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body. IL-1 is made mainly by one type of white blood cell, the macrophage, and helps another type of white blood cell, the lymphocyte, fight infections. It also helps leukocytes pass through blood vessel walls to sites of infection and causes fever by affecting areas of the brain that control body temperature. There are two forms of IL-1, alpha and beta, which act the same. IL-1 made in the laboratory is used as a biological response modifier to boost the immune system in cancer therapy. IL-1 is a type of cytokine. Also called interleukin-1.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)immune system (ih-MYOON SIS-tem)
The complex group of organs and cells that defends the body against infections and other diseases.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)immunodeficiency (IH-myoo-noh-dih-FIH-shun-see)
The decreased ability of the body to fight infections and other diseases.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)in vitro (in VEE-troh)
In the laboratory (outside the body). The opposite of in vivo (in the body).
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)incidence (IN-sih-dents)
The number of new cases of a disease diagnosed each year.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)ingestion (in-JES-chun)
Taking into the body by mouth.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)inhalation (IN-huh-LAY-shun)
In medicine, refers to the act of taking a substance into the body by breathing.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)intramuscular (IN-truh-MUS-kyoo-ler)
Within or into muscle. Also called IM.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)intravenous (IN-truh-VEE-nus)
Into or within a vein. Intravenous usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called IV.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)iron (I-urn)
An important mineral the body needs to make hemoglobin, a substance in the blood that carries oxygen from the lungs to tissues throughout the body. Iron is also an important part of many other proteins and enzymes needed by the body for normal growth and development. It is found in red meat, fish, poultry, lentils, beans, and foods with iron added, such as cereal.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)lentinan (LEN-tih-nun)
A beta-glucan (a type of polysaccharide) from the mushroom (shiitake mushroom). It has been studied in Japan as a treatment for cancer.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)leukemia (loo-KEE-mee-uh)
Cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of blood cells to be produced and enter the bloodstream.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)magnesium (mag-NEE-zee-um)
In medicine, a mineral used by the body to help maintain muscles, nerves, and bones. It is also used in energy metabolism and protein synthesis.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)neutrophil (NOO-troh-fil)
A type of immune cell that is one of the first cell types to travel to the site of an infection. Neutrophils help fight infection by ingesting microorganisms and releasing enzymes that kill the microorganisms. A neutrophil is a type of white blood cell, a type of granulocyte, and a type of phagocyte.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)oral (OR-ul)
By or having to do with the mouth.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)pancreatic (PAN-kree-A-tik)
Having to do with the pancreas.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)pneumonia (noo-MOH-nyuh)
A severe inflammation of the lungs in which the alveoli (tiny air sacs) are filled with fluid. This may cause a decrease in the amount of oxygen that blood can absorb from air breathed into the lung. Pneumonia is usually caused by infection but may also be caused by radiation therapy, allergy, or irritation of lung tissue by inhaled substances. It may involve part or all of the lungs.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)polysaccharide (PAH-lee-SA-kuh-ride)
A large carbohydrate molecule. It contains many small sugar molecules that are joined chemically. Also called glycan.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)potassium (puh-TA-see-um)
A metallic element that is important in body functions such as regulation of blood pressure and of water content in cells, transmission of nerve impulses, digestion, muscle contraction, and heartbeat.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)prostate (PROS-tayt)
A gland in the male reproductive system. The prostate surrounds the part of the urethra (the tube that empties the bladder) just below the bladder, and produces a fluid that forms part of the semen.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)prostate cancer (PROS-tayt KAN-ser)
Cancer that forms in tissues of the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum). Prostate cancer usually occurs in older men.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)protein (PROH-teen)
A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)quality of life (KWAH-lih-tee ... life)
The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)sensitivity (SEN-sih-TIH-vih-tee)
When referring to a medical test, sensitivity refers to the percentage of people who test positive for a specific disease among a group of people who have the disease. No test has 100% sensitivity because some people who have the disease will test negative for it (false negatives).
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)shiitake mushroom (shee-TAH-kee ...)
A dark oriental mushroom widely used as a food. Several anticancer substances have been found in shiitake mushrooms, including lentinan, which has been studied in Japan as a treatment for stomach and colorectal cancer. The scientific name is .
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)stomach (STUH-muk)
An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)tumor (TOO-mer)
An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)
