Ovarian epithelial cancer, fallopian tube cancer, and primary peritoneal cancer are diseases in which malignant (cancer) cells form in the tissue covering the ovary or lining the fallopian tube or peritoneum.

The ovaries are a pair of organs in the female reproductive system. They are in the pelvis, one on each side of the uterus (the hollow, pear-shaped organ where a fetus grows). Each ovary is about the size and shape of an almond. The ovaries make eggs and female hormones (chemicals that control the way certain cells or organs work).

The fallopian tubes are a pair of long, slender tubes, one on each side of the uterus. Eggs pass from the ovaries, through the fallopian tubes, to the uterus. Cancer sometimes begins at the end of the fallopian tube near the ovary and spreads to the ovary.

The peritoneum is the tissue that lines the abdominal wall and covers organs in the abdomen. Primary peritoneal cancer is cancer that forms in the peritoneum and has not spread there from another part of the body. Cancer sometimes begins in the peritoneum and spreads to the ovary.

Ovarian epithelial cancer is one type of cancer that affects the ovary. See the following PDQ treatment summaries for information about other types of ovarian tumors:

• Ovarian Germ Cell Tumors
• Ovarian Low Malignant Potential Tumors
• Childhood Ovarian Cancer Treatment

Ovarian epithelial cancer, fallopian tube cancer, and primary peritoneal cancer form in the same type of tissue and are treated the same way.

Women who have a family history of ovarian cancer are at an increased risk of ovarian cancer.

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk to your doctor if you think you may be at risk for ovarian cancer.

Risk factors for ovarian cancer include the following:

• Family history of ovarian cancer in a first-degree relative (mother, daughter, or sister).
• Inherited changes in the BRCA1 or BRCA2 genes.
• Other hereditary conditions, such as hereditary nonpolyposis colorectal cancer (HNPCC; also called Lynch syndrome).
• Endometriosis.
• Postmenopausal hormone therapy.
• Obesity.
• Tall height.

Older age is the main risk factor for most cancers. The chance of getting cancer increases as you get older.

Some ovarian, fallopian tube, and primary peritoneal cancers are caused by inherited gene mutations (changes).

The genes in cells carry the hereditary information that is received from a person’s parents. Hereditary ovarian cancer makes up about 20% of all cases of ovarian cancer. There are three hereditary patterns: ovarian cancer alone, ovarian and breast cancers, and ovarian and colon cancers.

Fallopian tube cancer and peritoneal cancer may also be caused by certain inherited gene mutations.

There are tests that can detect gene mutations. These genetic tests are sometimes done for members of families with a high risk of cancer. See the following PDQ summaries for more information:

• Ovarian, Fallopian Tube, and Primary Peritoneal Cancer Prevention
• Genetics of Breast and Gynecologic Cancers (for health professionals)

Women with an increased risk of ovarian cancer may consider surgery to lessen the risk.

Some women who have an increased risk of ovarian cancer may choose to have a risk-reducing oophorectomy (the removal of healthy ovaries so that cancer cannot grow in them). In high-risk women, this procedure has been shown to greatly decrease the risk of ovarian cancer. (See the PDQ summary on Ovarian, Fallopian Tube, and Primary Peritoneal Cancer Prevention for more information.)

Signs and symptoms of ovarian, fallopian tube, or peritoneal cancer include pain or swelling in the abdomen.

Ovarian, fallopian tube, or peritoneal cancer may not cause early signs or symptoms. When signs or symptoms do appear, the cancer is often advanced. Signs and symptoms may include the following:

• Pain, swelling, or a feeling of pressure in the abdomen or pelvis.
• Sudden or frequent urge to urinate.
• Trouble eating or feeling full.
• A lump in the pelvic area.
• Gastrointestinal problems, such as gas, bloating, or constipation.

These signs and symptoms also may be caused by other conditions and not by ovarian, fallopian tube, or peritoneal cancer. If the signs or symptoms get worse or do not go away on their own, check with your doctor so that any problem can be diagnosed and treated as early as possible.

Tests that examine the ovaries and pelvic area are used to diagnose and stage ovarian, fallopian tube, and peritoneal cancer.

The following tests and procedures may be used to diagnose and stage ovarian, fallopian tube, and peritoneal cancer:

• Physical exam and health history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
• Pelvic exam: An exam of the vagina, cervix, uterus, fallopian tubes, ovaries, and rectum. A speculum is inserted into the vagina and the doctor or nurse looks at the vagina and cervix for signs of disease. A Pap test of the cervix is usually done. The doctor or nurse also inserts one or two lubricated, gloved fingers of one hand into the vagina and places the other hand over the lower abdomen to feel the size, shape, and position of the uterus and ovaries. The doctor or nurse also inserts a lubricated, gloved finger into the rectum to feel for lumps or abnormal areas.
• CA125 assay: A test that measures the level of CA125 in the blood. CA125 is a substance released by cells into the bloodstream. An increased CA125 level can be a sign of cancer or another condition such as endometriosis.
• Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs in the abdomen, and make echoes. The echoes form a picture of body tissues called a sonogram. The picture can be printed to be looked at later.Some patients may have a transvaginal ultrasound.
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A very small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
• Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer. The tissue is usually removed during surgery to remove the tumor.

Certain factors affect treatment options and prognosis (chance of recovery).

The prognosis and treatment options depend on the following:

• The type of ovarian cancer and how much cancer there is.
• The stage and grade of the cancer.
• Whether the patient has extra fluid in the abdomen that causes swelling.
• Whether all of the tumor can be removed by surgery.
• Whether there are changes in the BRCA1 or BRCA2 genes.
• The patient’s age and general health.
• Whether the cancer has just been diagnosed or has recurred (come back).