Health Care Professional Information
Common Name
American dwarf palm tree, cabbage palm
Clinical Summary
Saw palmetto is a small, slow-growing palm native to southeastern United States. The fruits are a rich source of fatty acids and phytosterols and have been used to promote urination, reduce inflammation, and for treatment of prostatic conditions such as benign prostatic hyperplasia (BPH).
Saw palmetto has been studied in many controlled clinical trials. Whereas data from some studies indicate that it improves lower urinary tract symptoms in patients with benign prostatic hyperplasia (2) (3) (4) (5) (15) (17) (18) (26), conflicting data suggest no such effects (6) (14) (19) (28). A recent study showed that saw palmetto may benefit patients with chronic bacterial prostatitis when coadministered with Urtica dioica, curcumin and quercitin (16). Pretreatment with saw palmetto reduced intra- and postoperative complications in patients who underwent transurethral resection of the prostate and open prostatectomy (22). However, saw palmetto use was not associated with risk of prostate cancer (27).
Saw palmetto extract was found to inhibit growth of normal prostate cells and increase their sensitivity to radiation in vitro, but did not affect malignant prostate cancer cells (20). Due to the increased risk of normal tissue complications, patients should consult with a physician before using saw palmetto supplements during radiation therapy. There is an ongoing study to determine the effects of saw palmetto on symptom management during radiation therapy.
Purported Uses
- Benign prostatic hypertrophy (BPH)
- Inflammation
- Promote urination
- Prostate cancer
Constituents
- Fatty Acids: Capric, caprylic, lauric, cis-linoleic, myristic, palmitic and stearic acid
- Steroids: beta-sitosterol, campesterol, cycloartenol, lupeol, lupenone and stigmasterol
- Aliphatic alcohols
- Polyprenic compounds: Arabinose, flavonoids, galactose, glucose and uronic acid
- Anthranilic acid
- Carotenes
- Lipase
- Tannins
(12)
Mechanism of Action
Studies with a liposterolic extract of saw palmetto berries showed that it reduced the uptake by tissue specimens of both testosterone and dihydrotestosterone (DHT) by more than 40% suggesting antiandrogenic activity (7). Further, the extract inhibited binding of DHT to its receptor (8) and blocked the conversion of testosterone to DHT by inhibiting the activity of 5-alpha-reductase (9). The berries also inhibit cyclooxygenase and 5-lipoxygenase pathways, thereby preventing the biosynthesis of inflammation-producing prostaglandins and leukotrienes (10).
Pharmacokinetics
Analysis of saw palmetto components including lauric acid, oleic acid, and beta-sitosterol in rats revealed wide distribution. Highest concentrations were found in abdominal fat, prostate, and skin, while lesser amounts were found in bladder and liver.
(13)
Adverse Reactions
- Although infrequent, saw palmetto may cause intraoperative hemorrhage, GI complaints, nausea, vomiting, and diarrhea. It may also have additive anticoagulant effects and prolong bleeding time (11).
- A case of severe intraoperative hemorrhage following consumption of saw palmetto has been reported (11).
- Hematuria and coagulopathy were observed in a patient with use of saw palmetto (21).
- Acute pancreatitis was reported in a 65-year-old male following use of saw palmetto for one week before onset of symptoms. His condition improved after treatment and avoiding saw palmetto (23).
- A 58-year-old man experienced severe liver damage following consumption of saw palmetto to alleviate symptoms of BPH. His symptoms improved after discontinuing saw palmetto (24).
Herb-Drug Interactions
- Anticoagulants: Saw palmetto may have additive anticoagulant effect (11).
- UGT (Uridine 5'-diphospho-glucuronosyltransferase) substrates: Saw palmetto inhibits UGT enzymes in vitro and can increase the side effects of drugs metabolized by them (25).
- CYP 450 substrates: Saw palmetto inhibits cytochrome P450 3A4, 2D6, and 2C9 and may interfere with the actions of drugs metabolized by these enzymes (29)
Literature Summary and Critique
Bent S, et al. Saw Palmetto for Benign Prostatic Hyperplasia. N Engl J Med 2006; 354(6): 557- 566.
Two hundred and twenty-five men (over the age of 49 years) with moderate-to-severe symptoms of benign prostatic hyperplasia (BPH) were randomized to receive saw palmetto extract (160 mg twice a day) or placebo for one year. There was no significant difference in the primary outcome measures — the American Urological Association Symptom Index (AUASI) scores or the maximal urinary flow rates between patients taking saw palmetto or placebo. Also, no significant differences were observed in prostate size, residual volume after voiding, quality of life, or serum PSA levels between the two groups.
These data contradict several earlier studies in which saw palmetto appeared to be a promising alternative for BPH. Researchers point to the methodological flaws in those studies, including shorter duration of study, failure to use validated symptom scores, and ineffective blinding.
Dosage (Inside MSKCC Only)
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References
- Feifer AH, Fleshner NE, Klotz L. Analytical accuracy and reliability of commonly used nutritional supplements in prostate disease. J Urol 2002;168:150-4.
- Fagelman E, Lowe FC. Herbal medications in the treatment of benign prostatic hyperplasia (BPH). Urol Clin N Am 2002;29:23-9.
- Gerber G, et al. Saw palmetto (Serenoa repens) in men with lower urinary tract symptoms: effects on urodynamic parameters and voiding symptoms. Urology. 1998 Jun;51(6):1003-7.
- Boyle P, Robertson C, Lowe F, et al. Meta-analysis of clinical trials of permixon (saw palmetto) in the treatment of symptomatic benign prostatic hyperplasia. Urology 2000;55:533-9.
- Wilt TJ, Ishani A, Start G, et al. Saw palmetto extracts for treatment of benign prostatic hyperplasia: a systematic review. JAMA 1998;280:1604-9.
- Bent S, et al. Saw palmetto for benign prostatic hyperplasia. N Engl J Med 2006;354(6): 557-566.
- El-Sheikh MM, Dakkak MR, and Saddique A. The effect of Permixon on androgen receptors. Acta Obstet Gynecol Scand. 1988;67(5):397-9.
- Carilla E, Briley M, Fauran F, et al. Binding of Permixon, a new treatment for prostatic benign hyperplasia, to the cytosolic androgen receptor in the rat prostate.J Steroid Biochem 1984;20(1):521-3.
- Bayne CW, Donnelly F, Ross M, Habib FK. Serenoa repens (Permixon): a 5alpha-reductase types I and II inhibitor-new evidence in a coculture model of BPH. Prostate 1999;40(4):232-41.
- Goldmann WH, Sharma AL, Currier SJ, et al. Saw palmetto berry extract inhibits cell growth and Cox-2 expression in prostatic cancer cells. Cell Biol Int 2001;25:1117-24.
- Cheema P, El-Mefty O, Jazieh AR, et al. Intraoperative haemorrhage associated with the use of extract of Saw Palmetto herb: a case report and review of literature. J Intern Med. 2001 Aug;250(2):167-9.
- Newall C, Herbal Medicines: A Guide for Health-Care Professionals. London: Pharmaceutical Press; 1996.
- Chevalier G, et al. Distribution study of radioactivity in rats after oral administration of the lipido/sterolic extract of serenoa repens supplemented with [1-14C]-lauric acid, [1-14C]-oleic acid or [4-14C]-beta-sitosterol. Eur J Drug Metab Pharmacokinet 1997;22:73-83.
- Avins AL, Bent S, Staccone S, et al. A detailed safety assessment of a saw palmetto extract.Complement Ther Med. 2008 Jun;16(3):147-54.
- Shi R, Xie Q, Gang X, et al. Effect of saw palmetto soft gel capsule on lower urinary tract symptoms associated with benign prostatic hyperplasia: a randomized trial in Shanghai, China. J Urol. 2008 Feb;179(2):610-5.
- Cai T, Mazzoli S, Bechi A, et al. Serenoa repens associated with Urtica dioica (ProstaMEV) and curcumin and quercitin (FlogMEV) extracts are able to improve the efficacy of prulifloxacin in bacterial prostatitis patients: results from a prospective randomised study. Int J Antimicrob Agents. 2009 Jun;33(6):549-53.
- Lopatkin N, Sivkov A, Schläfke S, et al. Efficacy and safety of a combination of Sabal and Urtica extract in lower urinary tract symptoms—long-term follow-up of a placebo-controlled, double-blind, multicenter trial. Int Urol Nephrol. 2007;39(4):1137-46.
- Hizli F, Uygur MC. A prospective study of the efficacy of Serenoa repens, tamsulosin, and Serenoa repens plus tamsulosin treatment for patients with benign prostate hyperplasia. Int Urol Nephrol. 2007;39(3):879-86.
- Tacklind J, MacDonald R, Rutks I, Wilt TJ. Serenoa repens for benign prostatic hyperplasia. Cochrane Database of Systematic Reviews 2009, Issue 2. Art. No.: CD001423. DOI: 10.1002/14651858.CD001423.pub2.
- Hasan Y, Schoenherr D, Martinez AA, et al. Prostate-specific natural health products (dietary supplements) radiosensitize normal prostate cells. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3):896-904.
- Villanueva S, González J. Coagulopathy induced by saw palmetto: a case report. Bol Asoc Med P R. 2009 Jul-Sep;101(3):48-50.
- Anceschi R, Bisi M, Ghidini N, Ferrari G, Ferrari P. Serenoa repens (Permixon) reduces intra- and postoperative complications of surgical treatments of benign prostatic hyperplasia. Minerva Urol Nefrol. 2010 Sep;62(3):219-23.
- Wargo KA, Allman E, Ibrahim F. A possible case of saw palmetto-induced pancreatitis. South Med J. 2010 Jul;103(7):683-5.
- Lapi F, Gallo E, Giocaliere E, et al. Acute liver damage due to Serenoa repens: a case report. Br J Clin Pharmacol. 2010 May;69(5):558-60.
- Mohamed ME, Frye RF. Inhibitory Effects of Commonly Used Herbal Extracts on UGT1A4, 1A6, and 1A9 Enzyme Activities. Drug Metab Dispos. 2011 Jun 1. [Epub ahead of print]
- Sinescu I, Geavlete P, Multescu R, et al. Long-term efficacy of Serenoa repens treatment in patients with mild and moderate symptomatic benign prostatic hyperplasia. Urol Int. 2011;86(3):284-9. Epub 2011 Feb 8.
- Brasky TM, Kristal AR, Navarro SL, et al. Specialty supplements and prostate cancer risk in the VITamins and Lifestyle (VITAL) cohort. Nutr Cancer. 2011 May;63(4):573-82.
- Barry MJ, Meleth S, Lee JY, et al. Effect of Increasing Doses of Saw Palmetto Extract on Lower Urinary Tract Symptoms. A Randomized Trial. JAMA. 2011;306(12):1344-1351.
- Yale SH, Glurich I. Analysis of the inhibitory potential of Ginkgo biloba, Echinacea purpurea, and Serenoa repens on the metabolic activity of cytochrome P450 3A4, 2D6, and 2C9 . J Altern Complement Med. 2005 Jun;11(3):433-9.
Consumer Information
How It Works
Bottom Line: Saw palmetto was shown in some studies to help relieve the symptoms of benign prostatic hypertrophy (BPH), but it has not been shown to prevent or treat prostate cancer.
Studies in the laboratory and in animals show that saw palmetto works by countering the effects of androgens (the male sex hormones), such as testosterone and DHT. It is thought that saw palmetto does not reduce the levels of these hormones circulating in the blood, but causes body tissues (like the prostate) to take in lower levels of the hormones. Other studies have noted that saw palmetto reduces the conversion of testosterone to the DHT, its more potent form, by inhibiting the enzyme 5 alpha reductase. Saw palmetto berry extracts also reduce inflammation and edema in laboratory studies by inhibiting the formation of compounds that cause these reactions.
In a lab study, saw palmetto extract was found to slow the growth of normal prostate cells and increase their sensitivity to radiation, while not affecting prostate cancer cells. Since this may increase the risk of complications, patients should consult with a physician before using saw palmetto supplements during radiation therapy.
Purported Uses
- To treat benign prostatic hypertrophy (BPH)
Several clinical trials and meta-analyses have shown that saw palmetto improves urinary tract symptoms associated with BPH.
- To treat prostate cancer
Saw palmetto shows anti-inflammatory and anti-androgen properties in laboratory studies and reduces the levels of DHT in the prostate in clinical trials.
- As a diuretic
No scientific evidence supports this use.
- As an anti-inflammatory
Laboratory studies support this use, but human data are lacking.
Research Evidence
Benign prostatic hypertrophy (BPH)
Two hundred and twenty-five men (over the age of 49 years) with moderate-to-severe symptoms of benign prostatic hyperplasia (BPH) were given saw palmetto extract (160 mg twice a day) or placebo for one year. There was no significant difference in the American Urological Association Symptom Index (AUASI) scores or the maximal urinary flow rates between patients taking saw palmetto or placebo. Also, no significant differences were observed in prostate size, quality of life, or serum prostate specific antigen (PSA) levels between the two groups.
Do Not Take If
- You are taking warfarin or other blood thinners (Saw palmetto may increase the risk of bruising and bleeding).
- You are taking drugs that are substrates of UGT (Uridine 5'-diphospho-glucuronosyltransferase) enzymes (Saw palmetto may increase the risk of side effects of these drugs).
Side Effects
- Gastrointestinal complaints: nausea, vomiting, and diarrhea
- Saw palmetto may have additive anticoagulant effects and prolong bleeding time.
- A case of severe intraoperative hemorrhage following consumption of saw palmetto has been reported.
- Hematuria and coagulopathy were observed in a patient with use of saw palmetto.
- Acute pancreatitis was reported in a 65-year-old male following use of saw palmetto for one week before onset of symptoms. His condition improved after treatment and avoiding saw palmetto.
- A 58-year-old man experienced severe liver damage following consumption of saw palmetto to alleviate symptoms of BPH. His symptoms improved after discontinuing saw palmetto.
Last updated: September 29, 2012
acute (uh-KYOOT)
Symptoms or signs that begin and worsen quickly; not chronic.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)anti-inflammatory (AN-tee-in-FLA-muh-TOR-ee)
Having to do with reducing inflammation.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)anticoagulant (AN-tee-koh-A-gyuh-lunt)
A substance that is used to prevent and treat blood clots in blood vessels and the heart. Also called blood thinner.
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(http://www.cancer.gov/dictionary)antigen (AN-tih-jen)
Any substance that causes the body to make a specific immune response.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)benign (beh-NINE)
Not cancerous. Benign tumors may grow larger but do not spread to other parts of the body. Also called nonmalignant.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)benign prostatic hyperplasia (beh-NINE prah-STA-tik HY-per-PLAY-zhuh)
A benign (not cancer) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy and BPH.
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)BPH
A benign (not cancer) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hyperplasia and benign prostatic hypertrophy.
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.
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(http://www.cancer.gov/dictionary)chronic (KRAH-nik)
A disease or condition that persists or progresses over a long period of time.
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(http://www.cancer.gov/dictionary)clinical (KLIH-nih-kul)
Having to do with the examination and treatment of patients.
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(http://www.cancer.gov/dictionary)condition (kun-DIH-shun)
In medicine, a health problem with certain characteristics or symptoms.
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(http://www.cancer.gov/dictionary)curcumin (ker-KYOO-min)
A yellow pigment of the spice turmeric that is being studied in cancer prevention.
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(http://www.cancer.gov/dictionary)DHT
A hormone made from testosterone in the prostate, testes, and certain other tissues. It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. High amounts of DHT may increase the growth of prostate cancer and make it harder to treat. Also called androstanolone and dihydrotestosterone.
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(http://www.cancer.gov/dictionary)edema (eh-DEE-muh)
Swelling caused by excess fluid in body tissues.
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(http://www.cancer.gov/dictionary)enzyme (EN-zime)
A protein that speeds up chemical reactions in the body.
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(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.
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(http://www.cancer.gov/dictionary)gastrointestinal (GAS-troh-in-TES-tih-nul)
Refers to the stomach and intestines. Also called GI.
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(http://www.cancer.gov/dictionary)hematuria (HEE-muh-TOOR-ee-uh)
Blood in the urine.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)hemorrhage (HEH-muh-rij)
In medicine, loss of blood from damaged blood vessels. A hemorrhage may be internal or external, and usually involves a lot of bleeding in a short time.
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(http://www.cancer.gov/dictionary)hyperplasia (HY-per-PLAY-zhuh)
An abnormal increase in the number of normal cells in an organ or tissue.
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(http://www.cancer.gov/dictionary)in vitro (in VEE-troh)
In the laboratory (outside the body). The opposite of in vivo (in the body).
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(http://www.cancer.gov/dictionary)inflammation (IN-fluh-MAY-shun)
Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.
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(http://www.cancer.gov/dictionary)L
A measure of volume for a liquid, using the metric system. One L is equal to 1,000 cubic centimeters (cc), 1,000 milliliters (mm), or 1.0567 quarts (qt). Also called liter.
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(http://www.cancer.gov/dictionary)liver (LIH-ver)
A large organ located in the upper abdomen. The liver cleanses the blood and aids in digestion by secreting bile.
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(http://www.cancer.gov/dictionary)malignant (muh-LIG-nunt)
Cancerous. Malignant cells can invade and destroy nearby tissue and spread to other parts of the body.
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(http://www.cancer.gov/dictionary)mean (meen)
A statistics term. The average value in a set of measurements. The mean is the sum of a set of numbers divided by how many numbers are in the set.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)nausea (NAW-zee-uh)
A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.
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(http://www.cancer.gov/dictionary)open prostatectomy (… PROS-tuh-TEK-toh-mee)
Surgery to remove part or all of the prostate gland through an incision in the lower abdomen or perineum (the area between the anus and scrotum). An open prostatectomy may be done to remove an enlarged prostate gland in benign prostatic hyperplasia (BPH) or as a treatment for prostate cancer.
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(http://www.cancer.gov/dictionary)outcome (OWT-kum)
A specific result or effect that can be measured. Examples of outcomes include decreased pain, reduced tumor size, and improvement of disease.
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(http://www.cancer.gov/dictionary)pancreatitis (PAN-kree-uh-TY-tis)
Inflammation of the pancreas. Chronic pancreatitis may cause diabetes and problems with digestion. Pain is the primary symptom.
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(http://www.cancer.gov/dictionary)physician (fih-ZIH-shun)
Medical doctor.
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(http://www.cancer.gov/dictionary)placebo (pluh-SEE-boh)
An inactive substance or treatment that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo.
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(http://www.cancer.gov/dictionary)postoperative (post-AH-pruh-tiv)
After surgery.
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(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.
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(http://www.cancer.gov/dictionary)prostatitis (PROS-tuh-TY-tis)
Inflammation of the prostate gland.
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(http://www.cancer.gov/dictionary)PSA
A protein made by the prostate gland and found in the blood. PSA blood levels may be higher than normal in men who have prostate cancer, benign prostatic hyperplasia (BPH), or infection or inflammation of the prostate gland. Also called prostate-specific antigen.
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.
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(http://www.cancer.gov/dictionary)radiation (RAY-dee-AY-shun)
Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).
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(http://www.cancer.gov/dictionary)radiation therapy (RAY-dee-AY-shun THAYR-uh-pee)
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.
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(http://www.cancer.gov/dictionary)randomized
Describes an experiment or clinical trial in which animal or human subjects are assigned by chance to separate groups that compare different treatments.
(http://www.cancer.gov/dictionary)receptor (reh-SEP-ter)
A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific physiologic effect in the cell.
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(http://www.cancer.gov/dictionary)resection (ree-SEK-shun)
Surgery to remove tissue or part or all of an organ.
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(http://www.cancer.gov/dictionary)saw palmetto (...pawl-MEH-toh)
A shrub that is a member of the palm tree family. An extract made from the berries of this shrub has been studied in the treatment of certain urinary and prostate disorders. The scientific name is .
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).
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(http://www.cancer.gov/dictionary)serum (SEER-um)
The clear liquid part of the blood that remains after blood cells and clotting proteins have been removed.
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(http://www.cancer.gov/dictionary)significant (sig-NIH-fih-kunt)
In statistics, describes a mathematical measure of difference between groups. The difference is said to be significant if it is greater than what might be expected to happen by chance alone. Also called statistically significant.
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(http://www.cancer.gov/dictionary)steroid (STAYR-oyd)
Any of a group of lipids (fats) that have a certain chemical structure. Steroids occur naturally in plants and animals or they may be made in the laboratory. Examples of steroids include sex hormones, cholesterol, bile acids, and some drugs.
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(http://www.cancer.gov/dictionary)symptom (SIMP-tum)
An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)testosterone (tes-TOS-teh-rone)
A hormone made mainly in the testes (part of the male reproductive system). It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. Testosterone may also be made in the laboratory and is used to treat certain medical conditions.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)therapy (THAYR-uh-pee)
Treatment.
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(http://www.cancer.gov/dictionary)tissue (TIH-shoo)
A group or layer of cells that work together to perform a specific function.
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(http://www.cancer.gov/dictionary)urinary (YOOR-ih-NAYR-ee)
Having to do with urine or the organs of the body that produce and get rid of urine.
Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)urinary tract (YOOR-ih-NAYR-ee trakt)
The organs of the body that produce and discharge urine. These include the kidneys, ureters, bladder, and urethra.
Source: The National Cancer Institute's Dictionary of Cancer Terms
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