Ovarian cancer occurs when abnormal cells grow and form a tumor inside or on the surface of a person’s ovaries. Almost 20,000 women are diagnosed with ovarian cancer in the U.S. each year.
What is ovarian cancer?
The two ovaries are reproductive organs that sit on opposite sides of the uterus. The ovaries contain different types of cells, including surface epithelial cells, germ cells and sex-cord stromal cells. The ovaries contain eggs that are released monthly during ovulation. The ovaries also secrete the hormones estrogen and progesterone. Ovarian cancer develops when the cells of the ovary grow uncontrolled and form tumors.
The following three places are where ovarian cancer tumors (both benign and malignant) can form inside the ovaries.
- Epithelial cells: These tumors grow from cells on the surface of one or both ovaries. This is the most common type of ovarian cancer tumor. Approximately 95% of ovarian cancers are epithelial in origin. This includes high-grade serous, low-grade serous, mucinous, endometrioid and clear cell carcinomas. In addition, there is evidence that some types of epithelial ovarian cancers may arise from fallopian tube cells.
- Germ cells: These tumors develop from cells inside the ovaries that contain eggs. They include dysgerminomas, yolk sac tumors, embryonal carcinoma, choriocarcinoma and teratoma.
- Stromal cells: These tumors develop in the cells of the ovaries that produce hormones. These tumors include granulosa cell tumors, thecomas, fibromas and Sertoli-Leydig tumors.
Ovarian Cancer Symptoms
Ovarian cancer is often hard to detect in the early stages because there are few noticeable symptoms or signs of the disease. Many of the symptoms are vague and nonspecific, and can be associated with other common conditions.
Signs of ovarian cancer can include:
- Abnormal vaginal discharge or bleeding after menopause
- Bloating or swollen feeling in the stomach
- Feeling full very soon after starting to eat
- New urinary frequency
- New constipation or other changes in bowel movements
- Discomfort or pain in the pelvic area, abdomen or lower back
- Unexplained weight loss
Ovarian Cancer Risk Factors
Nobody knows exactly what causes ovarian cancer. The lifetime risk of being diagnosed with it is 1.3%. Common ovarian cancer risk factors include:
- Older age
- Genetic mutations. Approximately 15% of ovarian cancers are linked to genetic mutations. Most are due to BRCA1 (BReast CAncer gene 1) or BRCA2 (BReast CAncer gene 2) mutations. However, other mutations can also be associated with ovarian cancer, including Lynch syndrome.
- Family history of ovarian cancer: People with a relative diagnosed with ovarian cancer (such as a mother, sister, grandmother or aunt) have higher risk.
- Early menstruation and late menopause
- Never being pregnant
Lowering Ovarian Cancer Risk
Studies show you can do things to reduce the risk of ovarian cancer. These include:
- Eating a healthy diet and maintaining a healthy weight
- Consider taking birth control pills. Talk to your doctor about whether they may be a good option for you.
- Know your family history and consider genetic testing. Again, talk to your doctor.
- Consider having your fallopian tubes removed (salpingectomy). Studies indicate this could decrease your risk of ovarian cancer.
Ovarian Cancer Diagnosis
Unfortunately, there are no approved screening tests to detect ovarian cancer. If you have signs or symptoms of ovarian cancer, schedule an appointment to discuss them with your gynecologist, who can perform several tests to determine if you have ovarian cancer, including:
- Pelvic exam: Your doctor examines the inside of the vagina and the cervix and looks for abnormalities. The doctor also feels the size and shape of the uterus and ovaries, which can help identify a problem. A pelvic exam alone cannot rule out ovarian cancer.
- Imaging tests: Ultrasounds, MRI and/or CT scans of the abdomen and pelvic area allow a doctor to look at the ovaries more closely and detect abnormalities. They can also help the gynecologist decide whether to order more tests.
- Blood tests: If an ovarian mass is found by imaging, your doctor may order blood tests to help determine the likelihood that you have cancer. These tests don’t diagnose cancer, but they can help doctors decide the next best step in management.
- Surgery: Sometimes, the only way to find out if you have ovarian cancer is to have surgery to remove one or both ovaries. A pathologist will then test the ovary or ovaries for signs of cancer cells.
Ovarian Cancer Stages
Cancer staging helps you and your treatment team understand what areas of your body are affected and whether the cancer has spread outside of the ovaries.
- Stage 1: Cancer is only detected in one or both ovaries, or in the fallopian tubes. It has not spread to lymph nodes or other organs.
- Stage 2: Cancer cells are detected in one or both ovaries and has spread to nearby pelvic tissues. There is no cancer in nearby lymph nodes.
- Stage 3: The cancer has spread to the abdominal cavity outside/above the pelvis and/or has spread to the pelvic or para-aortic lymph nodes.
- Stage 4: Cancer cells have spread to distant organs, such as the lungs, liver or spleen. The cancer may also have invaded through the entire wall of the intestine.
Ovarian Cancer Treatment
There are many different types of ovarian cancer and treatment can include a combination of surgery, chemotherapy and/or hormonal therapy. Your gynecologic oncologist will make a treatment plan that is tailored to your specific type of cancer.
Surgery for Ovarian Cancer
The type of surgery recommended depends on the stage and spread of the cancer. Ovarian cancer surgeries include one or more of the following procedures.
- Salpingo-oophorectomy: removal of one or both fallopian tubes and ovaries
- Hysterectomy: removal of the uterus
- Pelvic and/or para-aortic lymphadenectomy: removal of lymph nodes in the abdomen and pelvis
- Omentectomy: removal of fatty tissue (omentum) that drapes over the intestines. Ovarian cancer has a high propensity to spread to the omentum.
- Cytoreduction (debulking): If cancer has spread throughout the abdomen, surgery to remove the cancer and affected organs may be recommended. This can be an extensive surgery that may include removal of other organs or parts of other organs, including the small and/or large intestine, bladder, liver, spleen and peritoneal surfaces throughout the abdomen. This type of surgery can be done before or after chemotherapy, depending on your situation.
Chemotherapy for Ovarian Cancer
Your doctor may recommend chemotherapy to kill cancer cells or to interfere with their ability to grow. Chemotherapy drugs can be given intravenously, and some can be taken by mouth. Chemotherapy may be given before and/or after surgery for ovarian cancer. In some situations, chemotherapy may be administered directly into the abdomen via an abdominal port (intraperitoneal chemotherapy), or it can be given intraoperatively during cytoreductive surgery as hyperthermic intraperitoneal chemotherapy (HIPEC).
Hormone Therapy for Ovarian Cancer
Hormones or hormone-blocking medications may be used to treat some types of ovarian tumors. These medications block the production of estrogen, lower estrogen levels or block estrogen from circulating where tumors can use it to grow.
Targeted Therapy for Ovarian Cancer
Targeted agents are drugs that focus on specific pathways in a tumor’s growth cycle. Your tumor’s individual molecular testing may be used to help determine which agents the tumor may respond to best.
Immunotherapy and Ovarian Cancer
Immunotherapy harnesses the body’s immune system to kill cancer cells. Depending on the tumor’s characteristics, your gynecologic oncologist may recommend immunotherapy treatment options.
Ovarian Cancer and Pregnancy
There are many types of ovarian cancer, and some people diagnosed with it can become pregnant. Using a combination of fertility-sparing surgery and therapies, some patients can go on to have children after treatment. A surgeon may be able to leave an unaffected ovary and/or the uterus intact if the cancer has not spread. In addition, there may be other fertility preservation options, including freezing of eggs and/or ovarian tissue. Your gynecologic oncologist and reproductive endocrinologist can help determine if these treatments and procedures may be options. It’s important to discuss your fertility goals with your doctor.
Ovarian Cancer Prognosis
The five-year survival rate for women diagnosed with ovarian cancer depends on the stage of cancer when diagnosed and the type of ovarian cancer.
- Local: About 93% survival when there is no sign of cancer outside the ovaries
- Regional: About 75% survival when cancer is detected outside the ovaries in nearby lymph nodes or organs
- Distant: About 31% survival when cancer cells spread to distant organs or faraway lymph nodes