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Consumers Home > Additional DES Resources > DES Glossary
DES Glossary

A • B • C • D • E • F • G • H • I • L • M • N • O • P • R • S • T • U • V • W

A

Adenocarcinoma: A cancer that begins in cells that line certain internal organs and that have glandular (secretory) properties.

Adenosis: Any disease of a gland or abnormal development of a gland. See also "vaginal adenosis."

Androgens: A family of hormones that promote the development and maintenance of male sex characteristics.

Autoimmune Disease: A condition in which the body recognizes its own tissues as foreign and directs an immune response against them. Examples include multiple sclerosis, rheumatoid arthritis, lupus, and diabetes mellitus.

B

Benign: Not cancerous; does not invade nearby tissue or spread to other parts of the body.

Benign Prostatic Hyperplasia (BPH): A benign (non-cancerous) 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.

Biopsy: The removal of cells or tissues for examination under a microscope. When only a sample of tissue is removed, the procedure is called an incisional biopsy or core biopsy. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. When a sample of tissue or fluid is removed with a needle, the procedure is called a needle biopsy or fine-needle aspiration. When a cone-shaped piece of tissue from the cervix and cervical canal is removed in a surgical procedure, it is called a cone biopsy or conization. Cone biopsy may be used to diagnose or treat a cervical condition.

British Randomized Trial: A group assembled to study DES-related health effects. Participants included women exposed to DES during pregnancy and men and women exposed before birth (in the womb). The DES-exposed group included 379 mothers, 144 daughters, and 177 sons. A control group of unexposed people included 371 mothers, 170 daughters, and 163 sons.

British Research Medical Council (BRMC) Study: Participants include pregnant diabetic women enrolled in clinical trial and DES Daughters and DES Sons identified through follow-up study. Total number of participants is 151 (79 DES-exposed and 72 unexposed).

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C

Cancer: A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic system to other parts of the body.

Cancer Information Service (CIS): CIS, part of the National Cancer Institute, is the federal government's principal resource for public information about cancer. CIS interprets and explains research findings in a clear and understandable manner and provides personalized responses to specific questions about cancer. Access CIS by calling 1-800-4-CANCER (1-800-422-6237) or by visiting the Web site at http://cis.nci.nih.gov.

Carcinoma: Cancer that begins in the skin or in tissues that line or cover internal organs.

Carcinoma In Situ: Cancer that involves only the cells in which it began and has not spread to nearby tissues.

Carcinosarcoma: A malignant (cancerous) tumor that is a mixture of carcinoma (cancer of epithelial tissue, which is skin and tissue that lines or covers the internal organs) and sarcoma (cancer of connective tissue, such as bone, cartilage, and fat).

Cervical: Relating to the neck, or the neck of any organ or structure. The cervix is the lower, narrow end (or neck) of the uterus.

Cervical Cancer: Refers to cancer of the uterine cervix. Routine screening for cervical cancer with Papanicolaou (Pap) testing is recommended for all women who are or have been sexually active and who have a cervix.

Cervical Intraepithelial Neoplasia (CIN): A general term for the growth of abnormal cells on the surface of the cervix.

Cervix: The lower, narrow end of the uterus that forms a canal between the uterus and vagina.

Clear Cell Adenocarcinoma (CCA):
Clear Cell Carcinoma: A rare type of tumor of the female genital tract in which the inside of the cells look clear when viewed under a microscope.
Adenocarcinoma: A cancer that begins in cells that line certain internal organs and that have glandular (secretory) properties.

Clinical Breast Examination: An examination by a medical professional during which the breasts are palpated (or lightly felt) with the hand and fingers to determine the condition underneath. Breast appearance is checked for dimpling, rashes, and nipple discharge.

Cohort: A group of people sharing common characteristics or experiences, often followed by a research study over long periods of time. By compiling and summarizing data from a cohort, scientists can observe whether disease conditions develop at higher rates in a cohort group than they would expect in the general population. The DES Combined Cohort Study (DCCS) is an example of research using a cohort.

Colposcopy: Examination of the vagina and cervix using a lighted magnifying instrument called a colposcope.

Complete Hysterectomy: A surgical procedure to remove the entire uterus, including the cervix. Also called total hysterectomy.

Connecticut Mothers Study: A group assembled as participants in DES-related research. The participants included women who delivered babies during 1946-1965, at medical offices in Fairfield and New Haven Counties, Connecticut. The participants included 1,706 DES-exposed mothers, and 1,405 unexposed mothers. The participants are now included in the DES Combined Cohort Studies.

Corticosteroids: Steroid-type hormones that have antitumor activity in lymphomas and lymphoid leukemias. In addition, corticosteroids may be used for hormone replacement and for the management of some of the complications of cancer and its treatment.

Cortisone: A natural steroid hormone produced in the adrenal gland. It can also be made in the laboratory. Cortisone reduces swelling and can suppress immune responses.

Cryptorchidism: A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, into the scrotum. Also called undescended testicles.

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D

Dieckmann Cohort A group assembled in 1974 to study DES-related health risks. Participants included approximately 800 women exposed to DES while pregnant and 800 unexposed mothers; approximately 400 women exposed to DES before birth (in the womb) and 400 women in a control group; and approximately 400 men exposed to DES before birth and 400 unexposed men. The 1974 group represented the second Dieckmann cohort. The first included mothers who were participants in a study at the University of Chicago in the early 1950s. Results based on the initial study indicated that DES was not effective in preventing miscarriages.

Diethylstilbestrol (DES) A synthetic estrogen that was developed in 1938 to supplement a woman's natural estrogen production. DES was prescribed by doctors for women who experienced miscarriages or premature deliveries. DES was originally considered effective and safe for both the pregnant woman and the developing baby. In the United States, an estimated 5-10 million persons were exposed to DES during 1938-1971. Since 1971, DES has been linked to an increased risk of clear cell carcinoma of the vagina and cervix, infertility, and pregnancy complications in women exposed to DES before birth (in the womb), known as DES Daughters. In addition, women who were prescribed DES while pregnant are at a modestly increased risk for breast cancer. Men exposed to DES before birth (in the womb), known as DES Sons, are at an increased risk for non-cancerous epididymal cysts.

Diethystilbestrol Adenosis Project (DESAD): The DESAD began in 1974 at Baylor College of Medicine, Gundersen Clinic, Massachusetts General Hospital, the Mayo Clinic, and the University of Southern California. The DESAD, the largest DES cohort, included 4,014 DES Daughters (women exposed to DES before birth) and 1,033 unexposed women. Exposed women had documented evidence of DES exposure through review of prenatal records or through physician referral. The DESAD was assembled to conduct studies to determine if DES Daughters were at an increased risk of health problems related to their DES exposure.

DES Combined Cohort Studies (DCCS): The DCCS combines previously established DES study group participants (cohorts). The combined groups include approximately 5,000 women exposed to DES during pregnancy and 4,000 unexposed mothers; 5,000 exposed and 2,500 unexposed daughters; and 2,000 exposed and 2,000 unexposed sons. The goal of the DCCS is to determine whether the risk for cancer among DES-exposed persons is increased as a result of exposure to DES. Other health outcomes (such as infertility and pregnancy outcomes) also are being investigated through the DCCS.

DES Mothers Study: The DES Mothers Study began in 1980. The participant group (cohort) included approximately 3,000 women exposed to DES while pregnant and 3000 unexposed women. These participants had delivered babies during 1940-1960 at Boston Lying-In Hospital, the Mayo Clinic, Dartmouth Medical School, and a private practice in Portland, Maine. Exposure status was determined through review of medical records. The cohort was created as a means to determine if women exposed to DES during pregnancy were at increased risk for cancer.

Dose-dependent: Refers to the effects of treatment with a drug. If the effects change when the dose of the drug is changed, the effects are said to be dose-dependent.

Dysplasia: Cells that look abnormal under a microscope but are not cancer.

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E

Ectopic Pregnancy: A pregnancy outside the uterus, typically in a fallopian tube.

Embryo: Early stage in the development of a plant or an animal. In vertebrate animals (those that have a backbone or spinal column), this stage lasts from shortly after fertilization until all major body parts appear. In humans, this stage lasts from about 2 weeks after fertilization until the end of the eighth week of pregnancy.

Endocrine Therapy: Treatment that adds, blocks, or removes hormones. For certain conditions (such as diabetes or menopause) hormones are given to adjust low hormone levels. To slow or stop the growth of certain cancers (such as prostate and breast cancer) hormones may be given to block the body's natural hormones. Sometimes surgery is needed to remove the source of hormones. Also called hormone therapy, hormonal therapy, and hormone treatment.

Endocrinologist: A doctor who specializes in diagnosing and treating hormone disorders.

Endometriosis: A noncancerous (benign) condition that occurs when tissue that looks like endometrial (uterine) tissue grows in abnormal places in the abdomen.

Endometrium: The layer of tissue that lines the uterus (womb).

Epididymal Cyst: A benign (non-cancerous) sac or capsule on the testes.

Epididymis: A cord-like structure along the back border of each testis. Sperm matures and is stored in the coiled duct that runs through this structure.

Epithelial: Refers to the cells that line the internal and external surfaces of the body.

Epithelium: A thin layer of tissue that covers organs, glands, and other structures within the body.

Estradiol: The most potent naturally occurring estrogen in humans.

Estrogen Replacement Therapy (ERT): Estrogen given to postmenopausal women or to women who have had their ovaries surgically removed. Hormones are given to replace the estrogen no longer produced by the ovaries.

Estrogens: A family of hormones that promote the development and maintenance of female sex characteristics. Estrogen is a generic term for estrus-producing compounds (female sex hormones) including estradiol, estriol, and estrone.

Etiology: The cause or origin of disease.

Excisional Biopsy: A surgical procedure in which an entire lump or suspicious area of tissue is removed for diagnosis. The tissue is then examined under a microscope.

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F

Fallopian Tubes: Part of the female reproductive tract; the long slender tubes through which eggs pass from the ovaries to the uterus.

Fetus: A developing unborn offspring in the uterus (womb). This stage of pregnancy begins 8 weeks after conception and lasts until birth.

Fibroid: A non-cancerous (benign) smooth-muscle tumor, usually in the uterus (womb) or digestive (gastrointestinal) tract. Also called leiomyoma.

Fine-needle Aspiration: The removal of tissue or fluid with a needle for examination under a microscope. Also called needle biopsy.

Focal: In terms of cancer, limited to a specific area.

Follow-up: Monitoring an person's health over time after treatment. This includes keeping track of the health of people who participate in a clinical study or clinical trial for a period of time, both during and after the study ends.

Food and Drug Administration (FDA): FDA, part of the United States Department of Health and Human Services, is the federal government's principal agency to promote and protect the public health by helping safe and effective products reach the market in a timely way and by monitoring products for continued safety after they are in use. In 1971, the FDA issued a Drug Bulletin advising physicians to stop prescribing DES to pregnant women because it was linked to a rare vaginal cancer in female offspring. The bulletin is titled FDA Drug Bulletin: Diethylstilbestrol Contraindicated in Pregnancy. Washington, DC: U.S. Department of Health, Education and Welfare (DHEW), 1971. You can access the FDA's Web site at www.fda.gov.

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G

Gene: The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.

Gland: An organ that produces and releases one or more substances for use in the body. Some glands produce fluids that affect tissues or organs. Others glands produce hormones.

Glucocorticoid: A substance that belongs to the family of compounds called corticosteroids (steroids). Glucocorticoids affect metabolism (chemical and physical changes in living cells). In addition glucocorticoids and have anti-inflammatory and immunosuppressive effects. They may be naturally produced (hormones) or synthetic (drugs).

Gonads: The part of the reproductive system that produces and releases eggs in females (ovaries) and sperm in males (testicles/testes).

Grade: When referring to a tumor, the grade indicates the level of abnormality found in the cancer cells when viewed through a microscope and how quickly the tumor is likely to grow and spread. Grading systems vary for each type of cancer.

Gynecologic: Having to do with the female reproductive tract (including the cervix, endometrium, fallopian tubes, ovaries, uterus, and vagina).

Gynecologic Cancer: Cancer of the female reproductive tract, including the cervix, endometrium, fallopian tubes, ovaries, uterus, and vagina.

Gynecologic Oncologist: A doctor who specializes in treating cancers of the female reproductive organs.

Gynecologist: A doctor who specializes in health conditions and problems related to the female reproductive organs.

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H

Half-life: The time required for half the amount of a substance (such as a drug or radioactive substance) in a living system (body tissue) or ecosystem to be eliminated or disintegrated by natural processes (decay or biological elimination).

High-grade Squamous Intraepithelial Lesion (HSIL): A pre-cancerous condition in which the cells of the uterine cervix are moderately or severely abnormal. Not all HSILs become cancerous, even if left untreated.

Hormonal Therapy: Treatment that adds, blocks, or removes hormones. For certain conditions (such as diabetes or menopause), hormones are given to adjust low hormone levels. To slow or stop the growth of certain cancers (such as prostate and breast cancer), hormones may be given to block the body's natural hormones. Sometimes surgery is needed to remove the source of hormones. Also called hormone therapy, hormone treatment, hormone replacement therapy, or endocrine therapy.

Hormone: Chemicals produced by glands in the body and circulated in the bloodstream. Hormones control the actions of certain cells or organs.

Hormone Replacement Therapy (HRT): Hormones (estrogen, progesterone, or both) given to postmenopausal women or women who have had their ovaries surgically removed to replace the estrogen no longer produced by the ovaries.

Hyperplasia: An abnormal increase in the number of cells in an organ or tissue.

Hypospadias: A developmental abnormality in males in which the urethra (opening of the penis) is misplaced on the underside of the penis.

Hysterectomy: An operation in which the uterus is removed.

Hysterosalpingogram: An X-ray that can check for differences and physical alterations in the female upper genital tract.

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I

Immune System: The complex group of organs and cells that defends the body against infection and disease.

Incidence: The number of new cases of a disease diagnosed each year.

Incisional Biopsy: A surgical procedure in which a portion of a lump or suspicious area of tissue is removed for diagnosis. The tissue is then examined under a microscope.

Infertility: The inability to produce children.

Inflammatory Breast Cancer: A type of breast cancer in which the breast looks red and swollen and feels warm. The skin of the breast may also show the pitted appearance called peau d'orange (like the skin of an orange). The redness and warmth occur because the cancer cells block the lymph vessels in the skin.

In Situ Cancer: Early cancer that has not spread to neighboring tissue.

Institutional Review Board (IRB): A group that may include scientists, physicians, clergy, and consumers at agencies and other facilities that participates in clinical trials. IRBs are designed to protect research participants. They review and must approve the action plan for every clinical trial. They check to see that the trial is well designed, does not involve undue risks, and includes safeguards for research participants.

Invasive Cervical Cancer: Cancer that has spread from the surface of the cervix to tissue deeper in the cervix or to other parts of the body.

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L

Laboratory Study: Research done in a laboratory. These studies may use test tubes or animals to find out if a drug, procedure, or treatment is likely to be useful. Laboratory studies take place before testing is done in humans.

Laboratory Test: A medical procedure that involves testing a sample of blood, urine, or other substance from the body. These tests can help determine a diagnosis, plan treatment, check to see if treatment is working, or monitor a disease over time.

Lesion: An area of abnormal tissue change.

Leuprolide: A drug that belongs to a family of drugs called gonadotropin-releasing hormone analogues. It is used to block hormone production in the ovaries or testicles.

Lupus: A chronic inflammatory connective tissue disease marked by skin rashes, joint pain and swelling, inflammation of the kidneys, inflammation of the fibrous tissue surrounding the heart, and other problems. Not all affected persons have all of these problems. Also called systemic lupus erythematosus.

Lutenizing Hormone-Releasing Hormone (LH-RH): A hormone that stimulates the production of sex hormones in men and women.

Lutenizing Hormone-Releasing Hormone (LH-RH) Agonist: A drug that inhibits the secretion of sex hormones. In men, LH-RH agonist causes testosterone levels to fall. In women, LH-RH agonist causes the levels of estrogen and other sex hormones to fall.

Lymph Gland: A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph glands are spread out along lymphatic vessels and contain many lymphocytes, which filter the lymphatic (lymph) fluid.

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M

Malignant: Cancerous; a growth with a tendency to invade and destroy nearby tissue and spread to other parts of the body.

Mammogram: An X-ray of the breast.

Mayo Clinic Sons Study: The Sons Study included approximately 800 men exposed to DES before birth (in the womb) and 600 unexposed men. This cohort was identified by review of medical records of women who gave birth at Mayo Clinic hospitals.

Menopause: The time of life when a woman's menstrual periods stop permanently. Also called change of life.

Menstrual Cycle: The monthly cycle of a woman's hormonal changes from the beginning of one menstrual period to the beginning of the next.

Menstruation: Periodic discharge of blood and tissue from the uterus (womb). Until menopause, menstruation occurs approximately every 28 days when a woman is not pregnant.

Microphallus: A smaller than normal penis.

Miscarriage: When a fetus leaves the uterus before the fifth month of pregnancy.

Myometrium: The muscular outer layer of the uterus.

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N

National Cancer Institute (NCI): Part of the National Institutes of Health of the United States Department of Health and Human Services. NCI is the federal government's principal agency for cancer research. NCI conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs regarding the cause, diagnosis, prevention, and treatment of cancer. Access the NCI Web site at www.cancer.gov.

National Institutes of Health (NIH): Part of the United States Department of Health and Human Services. NIH is the federal government's principal agency for biomedical research. NIH conducts research in its own laboratories; supports the research of non-federal scientists in universities, medical schools, hospitals, and research institutions throughout the country and abroad; helps in the training of research investigators; and fosters communication of medical information. Access the NIH Web site at www.nih.gov.

Neuroendocrine: Having to do with the interactions between the nervous system and the endocrine system. Certain cells release hormones into the blood in response to stimulation of the nervous system.

Nonmalignant: Not cancerous.

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O

Observation: Closely monitoring a patient's condition without treatment until symptoms appear or change. Also called watchful waiting.

Oncogene: A gene that normally directs cell growth. If altered, an oncogene can promote or allow the uncontrolled growth of cancer. Alterations can be inherited or caused by an environmental exposure to carcinogens.

Oncologist: A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer treatment. For example, a radiation oncologist specializes in treating cancer with radiation.

Oophorectomy: A surgical procedure to remove one or both ovaries.

Orchiectomy: A surgical procedure to remove one or both testicles.

Osteoporosis: A condition that is characterized by a decrease in bone mass and density and causes bones to become fragile.

Ovarian Suppression: A surgical procedure, radiation therapy, or a drug treatment to stop the functioning of the ovaries. Also called ovarian ablation.

Ovaries: The pair of female reproductive glands in which the eggs (ova) are formed. The ovaries are located in the pelvis, one on each side of the uterus (womb).

Ovulation: The release of an egg from an ovary during the menstrual cycle.

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P

Pap Smear: The collection of cells from the cervix for examination under a microscope. Pap smears are used to detect changes that may be cancer or may lead to cancer (pre-cancerous) and can detect non-cancerous conditions (such as infection or inflammation). Also called a Pap test.

Patient Advocate: A person who helps a patient work with others who have an effect on the patient's health, including doctors, insurance companies, employers, case managers, and lawyers. A patient advocate helps resolve issues about health care, medical bills, and job discrimination related to a patient's medical condition. Patient advocacy groups try to raise public awareness about important health issues (such as the need for support services, education, and research). Such groups work to bring about change that will help patients and their families.

Pelvic: Having to do with the pelvis (the lower part of the abdomen located between the hip bones).

Perimenopausal: The time in a woman's life when menstrual periods become irregular. Refers to the time near menopause.

Pilot Study: The initial study examining a new method or treatment.

Placenta: The organ that nourishes the developing fetus in the uterus.

Postmenopausal: The time in a woman's life after menopause.

Pre-cancerous: A term used to describe a condition that might or is likely to become cancer. Also called premalignant.

Premenopausal: The time in a woman's life before menopause.

Prescription: A doctor's order for medicine or another treatment.

Primary Care Physician: A doctor who manages a person's health care over time. A primary care physician can provide a wide range of care (including prevention and treatment) can discuss treatment choices, and can refer a patient to a specialist.

Progesterone: A female hormone.

Progesterone Receptor Negative (PR-): Breast cancer cells that do not have a protein (receptor molecule) to which progesterone will attach. Breast cancer cells that are PR- do not need the hormone progesterone to grow and usually do not respond to hormonal therapy.

Progesterone Receptor Positive (PR+): Breast cancer cells that have a protein (receptor molecule) to which progesterone will attach. Breast cancer cells that are PR+ need the hormone progesterone to grow and will usually respond to hormonal therapy.

Prospective: A research study or clinical trial in which participants are identified and then followed over time.

Prostate: A gland in the male reproductive system just below the bladder. The prostate surrounds part of the urethra, the canal that empties the bladder, and produces a fluid that forms part of semen.

Prostate-Specific Antigen (PSA): A substance produced by the prostate that may be found in an increased amount in the blood of men who have prostate cancer, benign prostatic hyperplasia, or infection or inflammation of the prostate.

p-value: A term used in statistics. A p-value expresses statistical significance in scientific studies. P-values are calculated using a statistical formula that includes the number of people and health effects being studied. It is designed to answer the question, "Could a group of this many people, who all experienced a common exposure, have had this health problem in common by chance alone?" It is standard practice to consider a finding statistically significant if there is less than a 5% probability (p=.05 or less) that the findings resulted from chance. Conversely, if there is greater than a 5% probability (p=.06 or greater) that a finding was due to chance, the finding is not statistically significant.

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R

Raloxifene: A drug that belongs to the family of drugs called selective estrogen receptor modulators (SERMs) and is used in the prevention of osteoporosis in postmenopausal women. Raloxifene is also being studied as a cancer-prevention drug.

Receptor: 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.

Registry for Research on Hormonal Transplacental Carcinogenesis: The Registry was established at Massachusetts General Hospital in 1971 to track incidence of clear cell adenocarcinoma (CCA) of the vagina or cervix. Originally numbering 21 cases, by 2002 approximately 750 cases were recorded at the registry. Most of the information on treatment outcome and recurrence rates of CCA has come from the study of patients in the Registry. The registry is now located at the University of Chicago (Department of Obstetrics and Gynecology, The University of Chicago, 5841 South Maryland Avenue, Mail Code 2050, Chicago, IL 60637. Phone: 773-702-6671. Fax: 773-702-5161).

Reproductive Cells: Egg and sperm cells. Each mature reproductive cell carries a single set of 23 chromosomes.

Reproductive System: In women, this system includes the ovaries, fallopian tubes, uterus (womb), cervix, and vagina (birth canal). The reproductive system in men includes the prostate, testes, and penis.

Retrospective Study: A study that looks backward in time, usually using medical records and interviews with patients who already have or had a disease.

Risk Factor: Anything that increases a person's chance of developing a disease, including a substance, agent, genetic alteration, trait, habit, or condition.

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S

Salpingo-Oophorectomy: A surgical procedure to remove the fallopian tubes and ovaries.

Sarcoma: A cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

Scrotum: In males, the external sac that contains the testicles.

Selective Estrogen Receptor Modulator (SERM): A drug that acts like estrogen on some tissues but blocks the effect of estrogen on other tissues. Tamoxifen and raloxifene are SERMs.

Semen: The fluid that is released through the penis during orgasm. Semen is made up of sperm from the testicles and fluid from the prostate and other sex glands.

Seminal Fluid: The fluid from the prostate and other sex glands that helps transport sperm out of the man's body during orgasm. Seminal fluid contains sugar as an energy source for sperm.

Seminal Vesicles: Glands that help produce semen.

Side Effects: Problems that occur when treatment affects healthy cells. For example, common side effects of cancer treatment are fatigue, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

Speculum: An instrument used to widen an opening of the body to make it easier to look inside.

Squamous Cell Carcinoma: Cancer that begins in squamous cells, which are thin, flat cells resembling fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts. Also called epidermoid carcinoma.

Squamous Cells: Flat cells that look like fish scales under a microscope. These cells cover internal and external surfaces of the body.

Squamous Intraepithelial Lesion (SIL): A general term for the abnormal growth of squamous cells on the surface of the cervix. The changes in the cells are described as low grade or high grade, depending on how much of the cervix is affected and how abnormal the cells appear.

Statistically Significant: A statistical concept used to determine causal links or associations in scientific studies. Statistical significance is expressed in scientific studies by a probability value (p value). P-values are calculated using a statistical formula that includes the number of people and health effects being studied and is designed to answer the question, "Could a group of this many people, who all experienced a common exposure, have had this health problem in common by chance alone?" It is standard practice to consider a finding statistically significant if there is less than a 5% probability (p=.05 or less) that the findings resulted from chance. Conversely, if there is greater than a 5% probability (p=.06 or greater) that a finding was due to chance, the finding is not statistically significant.

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T

T-shaped Uterus: A structural malformation in which the uterus resembles the letter "T" rather than the letter "U."

Tamoxifen: An anticancer drug that belongs to the family of drugs called antiestrogens. Tamoxifen blocks the effects of the hormone estrogen in the body. It is used to prevent or delay the return of breast cancer or to control its spread.

Testosterone: A hormone that promotes the development and maintenance of male sex characteristics.

Third Generation: The offspring (children) of DES Daughters or Sons. Also called DES Grandchildren.

Total Hysterectomy: Surgery to remove the entire uterus, including the cervix. Also called complete hysterectomy.

Tubal Ligation: An operation to tie the fallopian tubes closed. This procedure prevents pregnancy by blocking the passage of eggs (ova) from the ovaries to the uterus (womb).

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U

Undescended Testicles: A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, into the scrotum. Also called cryptorchidism.

Urologist: A physician who specializes in diseases of the urinary organs in females and the urinary and sex organs in males.

Uterus: The small, hollow, pear-shaped organ in a woman's pelvis. This is the organ in which a fetus develops. Also called the womb.

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V

Vagina: The muscular canal extending from the uterus to the exterior of the body. Also called the birth canal.

Vaginal Adenosis: Cellular changes on the surface of the vagina. Adenosis is a type of tissue on the surface of the vagina that is usually not found on the vagina. Vaginal adenosis is benign (non-cancerous). Over time, vaginal adenosis is usually replaced by normal tissue. Monitoring adenosis is recommended, but no treatment is necessary.

Vulva: The external female genital organs, including the clitoris, vaginal lips, and the opening to the vagina.

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W

Womb: The small, hollow, pear-shaped organ in a woman's pelvis. This is the organ in which a fetus develops. Also called the uterus.


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