Gynecologic cancers

Definition

Gynecologic cancers are malignant tumors within the female reproductive organs.

Description

Gynecologic cancers account for approximately 13% of all cancers that affect women. They are responsible for 10% of the cancer deaths among women.

The female reproductive tract is comprised of the ovaries, fallopian tubes, uterus, cervix, vagina, and vulva. Together, these organs allow a woman to become pregnant, protect and nourish an unborn baby, and to give birth. An understanding of each organ and its role in reproduction may help the patient to understand her particular gynecologic cancer. There are two ovaries, which are the internal organs dedicated to producing eggs. Released eggs are captured by the fallopian tubes, through which the egg (or fertilized egg) travels to the womb (uterus). The lining of the uterus (endometrium) responds to female hormones, such as estrogen, and becomes thickened to allow for implantation of a fertilized egg. The cervix is the opening of the uterus which opens (dilates) during labor to allow for passage of the baby. The vagina is a short tube that extends from the outer female genitalia (vulva) to the cervix.

Gynecologic cancers are defined not solely by the organ affected but also by the type of cancerous cells in the tumor. The type of cancer depends on the cell types that make up an organ. Adenocarcinomas are cancers that contain primarily cells originating from glands or ducts. Squamous cell carcinomas are tumors that arose from squamous cells, the main cell type found in skin. Sarcomas are cancers that originated from cells of basic connective tissue (mesenchymal cells). Sarcomas are comprised of cells that have become specialized (differentiated) and are named according to the predominant cell type. Endometroid tumors are those that originated from the endometrium. Clear-cell carcinoma is a rare gynecologic tumor that contains cells from the mullerian duct, which gives rise to the uterus, vagina, and fallopian tubes during development.

Because the reproductive organs are interconnected, spread of cancer from one organ to another (direct extension) is not uncommon. Gynecologic cancer carries the

name of the organ where the cancer originated (primary cancer site). For example, a tumor restricted to the vagina would be "primary vaginal cancer, " whereas one that has extended from the cervix to the vagina would be "primary cervical cancer."

Types of cancers

Ovarian cancer is the second most common cancer of the female reproductive organs. It accounts for 30% of all gynecologic cancers and 53% of the deaths in this group. The high death rate associated with ovarian cancer is due to the fact that most women are not diagnosed until the cancer has progressed to an advanced stage. The average age at diagnosis is 63 years. Serous carcinomas are the most common type of ovarian cancer. Other common types of ovarian cancer include mucinous tumors and endometroid tumors.

Fallopian tube cancers, as primary cancers, are very rare. They frequently spread widely within the abdominal cavity. Although often diagnosed earlier than ovarian cancer, fallopian tube cancer produces similar symptoms and originates from similar cell types as ovarian cancer.

Uterine cancer, also called endometrial cancer , is the most common gynecologic cancer and accounts for 46% of the cases. Endometrial cancer primarily affects postmenopausal women, however, 25% of cases are in premenopausal women. There are two types of endometrial cancer: estrogen-dependent and non-estrogen-dependent. Estrogen-dependent cancers are usually comprised of well-differentiated cells and are associated with a good outcome and a long survival time. Nonestrogen-dependent cancers are usually made up of poorly-differentiated cells and are invasive and associated with a poor prognosis. Uterine tumors are most frequently endometroid tumors, usually adenocarcinomas. Clear-cell carcinomas, papillary serous, sarcomas, and mixed tumors also occur.

Cervical cancer is the third most common cancer of the female reproductive tract. It accounts for 17% of the gynecologic cancers. Although cervical cancer can affect any adult woman, there are peaks of occurrence around the ages of 37 years and 62 years. Between 60% and 80% of the cases of cervical cancer are squamous cell carcinomas with the remainder being adenocarcinomas. Clear-cell carcinoma, serous carcinoma, and glassy-cell carcinoma are less frequent cervical cancers. Cervical cancer is very strongly associated with human papilloma virus .

Vaginal cancer is rare and accounts for just 3% of the gynecologic cancers. It most often strikes women in their sixties. Greater than 90% of the vaginal cancers are squamous cell carcinomas. Adenocarcinoma, melanoma , and sarcoma account for the remaining cases. There is an association between vaginal cancer and human papilloma virus.

Vulvar cancer is rare and accounts for 4% of the gynecologic cancers. It most often strikes women in their sixties. Squamous cell carcinoma is the most common type and melanoma is the second most common type of vulvar cancer. Other types of vulvar cancer include basal cell carcinoma , Paget's disease, and adenocarcinomas (arising from the Bartholin's, Skene's, or sweat glands). There is an association between vulvar cancer and human papilloma virus.

Resources

BOOKS

Fields, A., J. Jones, G. Thomas, and C. Runowicz. "Gynecologic Cancer." In Clinical Oncology. Lenhard, Raymond, Robert Osteen, and Ted Gansler, eds. Atlanta: American Cancer Society, 2000.

PERIODICALS

Brown, Jean, and Anne Cloutier. "Gynecologic Cancers."American Journal of Nursing 100 (April 2000): 32-5.

Zanotti, Kristine, and Alexander Kennedy. "Screening for Gynecologic Cancer." Medical Clinics of North America 83, no. 6 (November 1999): 1467-87.

ORGANIZATIONS

American Cancer Society. 1599 Clifton Rd. NE, Atlanta, GA 30329. (800) ACS-2345. <http://www.cancer.org>.

Cancer Research Institute, National Headquarters. 681 Fifth Ave., New York, NY 10022. (800) 992-2623. <http://www.cancerresearch.org>.

Gynecologic Cancer Foundation. 401 N. Michigan Ave., Chicago, IL 60611. (800) 444-4441 or (312) 644-6610. <http://www.wcn.org/gcf>.

National Institutes of Health. National Cancer Institute. 9000Rockville Pike, Bethesda, MD 20982. (800) 4-CANCER. <http://cancernet.nci.nih.gov>.

Belinda Rowland, Ph.D.

KEY TERMS

Differentiated

—A term describing cells that have become specialized and have matured normally, such as muscle cells.

Direct extension

—The spread of cancer directly from one organ to a neighboring organ, such as from the cervix to the vagina.

Glassy cell carcinoma

—Tumorous cells that have a glass-like appearance

Human papilloma virus (HPV)

—A sexually-transmitted virus that causes genital warts. It is associated with certain gynecologic cancers.

Mucinous tumors

—Adenocarcinomas that produce significant amounts of the complex sugar molecule known as mucin.

Papillary serous carcinoma

—A serous carcinoma with papillary (nipple-like) outgrowths.

Primary cancer (or tumor)

—The organ in which a cancerous tumor originated.

Serous carcinoma

—A carcinoma that produces or contains serum, the liquid portion of blood.