The ovaries are female reproductive organs located in the pelvis. There are two of them — one on each side of the uterus. The ovaries produce eggs and the female hormones estrogen and progesterone. Estrogen and progesterone control the development of female body characteristics — for example, breasts, body shape and body hair — and regulate the menstrual cycle and pregnancy.

What is ovarian cancer?

Ovarian cancer is a disease in which cancer starts in the cells of the ovary. There are three types of ovarian tumors, each named for the tissue in which they are found:

• Epithelial cell tumors: These tumors form from cells that cover the surface of the ovary. Epithelial cell tumors account for the majority of ovarian tumors.

• Germ cell tumors: These tumors develop from the cells that make the eggs in the ovary.

• Stromal cell tumors: These tumors develop in the cells of the structural tissue of the ovary responsible for producing female hormones.

Malignant (cancerous) ovarian tumors can grow and spread to other parts of the body. Doctors may recommend several treatment options for malignant tumors.

The majority of ovarian tumors are benign (noncancerous). Doctors may choose to treat benign ovarian tumors by completely removing the ovary or by removing the part of the ovary containing the tumor.

What is extra-ovarian primary peritoneal carcinoma (EOPPC)?

EOPPC is a cancer closely related to epithelial ovarian cancer. Its microscopic features and national history of disease and prognosis are identical to epithelial ovarian cancer. It occurs outside the ovary, in the peritoneum, which is the lining of the abdomen (belly). Because it occurs outside the ovary, women who have had their ovaries removed can still develop this type of cancer.

EOPPC can mimic ovarian cancer in terms of symptoms and can also cause an increase in the CA-125 tumor marker. Treatment is similar to that for ovarian cancer and includes surgery and chemotherapy.

Ovarian Cancer Prevention

There is no known method for preventing ovarian cancer. However, research has shown that there are certain proactive measures women can take to lower their risk. They include:

• Adhering to a healthy diet (high in fruits, vegetables and grains, and low in saturated fat)

• Staying at a healthy weight throughout life

• Using birth control pills

• Becoming pregnant and choosing to breast-feed

• Undergoing an oophorectomy, a surgical removal of ovaries, if you're at high risk for ovarian cancer

Ovarian Cancer Causes and Risk Factors

The cause of ovarian cancer is unknown, but there are certain risk factors that can raise a woman's chance of developing the disease. Risk factors include:

• Age (over the age of 55)

• Hormone replacement therapy: Some studies have suggested that women who use hormone replacement therapy after menopause may have a slightly increased risk of ovarian cancer.

• Infertility (inability to become pregnant)

• Personal history of breast or colon cancer

• Family history: First-degree relatives, such as a mother, daughter or sister, of a woman who has had ovarian cancer are at risk for developing the disease. The risk increases if two or more first-degree relatives have had ovarian cancer. A family history of breast, endometrial and/or colon cancer is also associated with an increased risk of developing ovarian cancer (hereditary nonpolyposis colorectal cancer).

• Mutations of the BRCA1 and/or BRCA 2 genes

• Certain fertility drugs

• Being obese may slightly increase a woman’s risk for developing ovarian cancer.

Ovarian Cancer Symptoms

Many ovarian cancer symptoms resemble other medical conditions or problems. It is important to pay attention to your body and know what is normal for you. The following are the most common symptoms of ovarian cancer. Each individual may experience symptoms differently.

• General discomfort in the lower abdomen, including any or all of the following:

  • Feeling swollen or bloated

  • A loss of appetite or a feeling of fullness — even after a light meal

  • Gas, indigestion and nausea

• Diarrhea, constipation or frequent urination caused by the growing tumor, which may press on nearby organs, such as the bowel or bladder

• Feeling very tired all the time

• Bleeding from the vagina

• Buildup of fluid around the lungs, which may cause shortness of breath

If any of these symptoms occur almost daily or last a few weeks and are new, they should be reported to a doctor. In many cases, symptoms do not occur until the ovarian cancer is in an advanced stage, meaning it has spread beyond the ovary in which it started. Always consult your doctor for a diagnosis.

Ovarian Cancer Diagnosis

Diagnosis includes a medical history and physical examination, including a pelvic examination to check the vagina, rectum and lower abdomen for masses or growths. A Pap test may be done as part of the pelvic examination. However, a Pap test cannot detect ovarian cancer. The definitive diagnosis is made at the time of surgery. The doctor may also order other tests, such as:

• Ultrasound. This imaging technique uses sound waves to produce an image on a monitor of the abdominal organs, such as the uterus, liver and kidneys.

• Computed tomography (CT or CAT scan). This noninvasive diagnostic imaging procedure uses a combination of X-rays and computer technology to produce horizontal, or axial, images (often called slices) of the body. The CT scan may indicate enlarged lymph nodes — a possible sign of a spreading cancer or infection.

• Lower gastrointestinal (GI) series. X-rays of the colon and rectum are taken using a contrast dye called barium.

• Intravenous pyelogram (IVP). X-rays of the kidneys and ureters are taken after the injection of a dye.

• Blood test: This is used to measure a substance in the blood called CA-125 — a tumor marker that is often found to be elevated in the blood of women with ovarian cancer. It is more often used to monitor the progress of treatment. It is not a screening test, since noncancerous conditions can cause levels to be elevated.

• Biopsy: This procedure removes tissue samples from the ovary for examination under a microscope. This is done to see if cancer or other abnormal cells are present. The diagnosis of cancer is confirmed only by a biopsy.

Treatment for ovarian cancer

Specific treatment for ovarian cancer will be determined by your doctor based on:

• Your overall health and medical history

• Extent of the disease

• Your tolerance for specific medications, procedures or therapies

• Expectations for the course of the disease

It's very important that your particular findings be put into context by an expert. Gynecologic oncologists are subspecialists with advanced training in the diagnosis, treatment and surveillance of female cancers, including ovarian cancer.

Ovarian cancer may be treated with surgery, chemotherapy or a combination of treatments.

• Surgery, which may include:

  • Salpingo-oophorectomy: surgery to remove the fallopian tubes and ovaries

  • Hysterectomy: surgical removal of the uterus

  • Pelvic lymph node dissection: removal of some of the lymph nodes from the pelvis

  • Para-aortic lymphadenectomy: removal of lymph nodes that surround the aorta, the main artery of the heart

  • Omentectomy: removal of the omentum, a layer of fatty tissue that surrounds organs in the lower gastrointestinal tract

  • Cytoreduction surgery or debulking: removal of the entire visible tumor, possibly including removal of the spleen and organs of the gastrointestinal tract

• Chemotherapy: This is the use of anticancer drugs to treat cancerous cells. In most cases, chemotherapy works by interfering with cancer cells’ ability to grow or reproduce. Different groups of drugs work in different ways to fight cancer cells. Oncologists will recommend a treatment plan for each individual. Usually, chemotherapy is given intravenously. Another way to treat ovarian cancer is through intraperitoneal chemotherapy. This type of chemotherapy is given directly into the abdomen through a long, thin tube called a catheter. It is only used for women with ovarian cancer that has spread to the inside of the abdomen.

• Immunotherapy: This approach uses drugs or vaccines to boost the immune system’s natural defenses so it can kill cancer cells. While there is a growing list of individual immunotherapy drugs approved for certain types of cancer, these drugs haven’t been as effective in ovarian cancer. Clinical trials, which may be available to some patients, are testing combinations of immunotherapy drugs, as well as a vaccine that targets mesothelin. Researchers are hopeful that these studies will result in better outcomes for patients. Learn more about cancer immunotherapy.

• Radiation therapy: This form of cancer treatment uses high-energy X-rays or particles to destroy cancer cells. Radiation is often used to shrink tumors and manage symptoms in patients with ovarian cancer that cannot be surgically removed as part of initial treatment or that has returned. For example, patients with vaginal bleeding due to recurrence from ovarian cancer benefit from radiation that alleviates the symptoms associated with bleeding. Radiation may also be used after surgery for selected patients, based on the type of ovarian cancer that was detected and how extensive the cancer was at the time of surgery.

The radiation techniques used to treat ovarian cancer may include precision external beam radiation, including intensity-modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT).