Pedro T. Ramirez, MD, Professor, Department of Gynecologic Oncology and Reproductive Medicine, David M. Gershenson Distinguished Professor in Ovarian Cancer Research, and Director of Minimally Invasive Surgical Research and Education, The University of Texas MD Anderson Cancer Center;Gloria Salvo, MD, Rotating Research Resident, Department of Gynecologic Oncology and Reproductive Medicine, MD Anderson Cancer Center
Ovarian cancer may not cause symptoms until it is large or has spread.
If doctors suspect ovarian cancer, blood tests, ultrasonography, and magnetic resonance imaging or computed tomography are done.
Usually, both ovaries, both fallopian tubes, and the uterus are removed.
Chemotherapy is often needed after surgery.
Cancer of the ovaries (ovarian carcinoma) develops most often in women aged 50 to 70. This cancer eventually develops in about 1 of 70 women. In the United States, it is the second most common gynecologic cancer. However, more women die of ovarian cancer than of any other gynecologic cancer. It is the fifth most common cause of cancer deaths in women.
Locating the Internal Female Reproductive Organs
There are many types of ovarian cancer. They develop from the many different types of cells in the ovaries. Cancers that start on the surface of the ovaries (epithelial carcinomas) account for at least 80%. Most other ovarian cancers start from the cells that produce eggs (called germ cell tumors) or in connective tissue (called stromal cell tumors). Germ cell tumors are much more common among women younger than 30. Sometimes cancers from other parts of the body spread to the ovaries.
Ovarian cancer can spread as follows:
Directly to the surrounding area
Through the shedding of cancer cells into the abdominal cavity
Through the lymphatic system to other parts of the pelvis and abdomen
Less often, through the bloodstream, eventually appearing in distant parts of the body, mainly the liver and lungs
Factors that increase the risk of ovarian cancer include the following:
Being older (the most important)
Having a first-degree relative (mother, sister, or daughter) who has had ovarian cancer
Not having any children
Having a first child late in life
Starting menstruating early
Having menopause late
Having had cancer of the uterus, breast, or large intestine (colon) or having a family member who has had one of these cancers
About 5 to 10% of cases are related to mutations in the BRCA1 and BRCA2 genes, which are also involved in some breast cancers. When mutations in these genes or other rare gene mutations are involved, ovarian and breast cancers tend to run in families. Such cancers are sometimes called hereditary breast and ovarian cancer syndromes. For women who have a BRCA1 mutation, the lifetime risk of developing ovarian cancer is 39%. Risk is less (11 to17%) for women with a BRCA2 mutation. The BRCA1 and BRCA2 genes are most common among Ashkenazi Jewish women.
Ovarian cancer causes the affected ovary to enlarge. In young women, enlargement of an ovary is likely to be caused by a noncancerous fluid-filled sac (ovarian cyst). However, after menopause, an enlarged ovary can be a sign of ovarian cancer.
Many women have no symptoms until the cancer is advanced. The first symptom may be vague discomfort in the lower abdomen, similar to indigestion. Other symptoms may include bloating, loss of appetite (because the stomach is compressed), gas pains, and backache. Ovarian cancer rarely causes vaginal bleeding.
Eventually, the abdomen may swell because the ovary enlarges or fluid accumulates in the abdomen (called ascites). At this stage, pain in the pelvic area, anemia, and weight loss are common.
Rarely, germ cell or stromal cell tumors produce estrogens, which can cause tissue in the uterine lining to grow excessively and breasts to enlarge. Or these tumors may produce male hormones (androgens), which can cause body hair to grow excessively, or hormones that resemble thyroid hormones, which can lead to hyperthyroidism.
Sometimes computed tomography or magnetic resonance imaging
Diagnosing ovarian cancer in its early stages is difficult because symptoms usually do not appear until the cancer is quite large or has spread beyond the ovaries and because many less serious disorders cause similar symptoms.
If doctors detect an enlarged ovary during a physical examination or suspect ovarian cancer based on symptoms, ultrasonography is done first. Sometimes computed tomography (CT) or magnetic resonance imaging (MRI) is used to help distinguish an ovarian cyst from a solid cancerous mass. If advanced cancer is suspected, CT or MRI is usually done before surgery to determine extent of the cancer.
If cancer seems unlikely, doctors reexamine the woman periodically.
If doctors suspect cancer or test results are unclear, blood tests are usually done to measure levels of substances that may indicate the presence of cancer (tumor markers), such as cancer antigen 125 (CA-125). Abnormal tumor marker levels alone do not confirm the diagnosis of cancer, but when combined with other information, they can support the diagnosis.
To confirm the diagnosis of ovarian cancer and to determine whether and how far the cancer has spread (its stage), doctors examine the ovaries in one of two ways:
Laparoscopy: Doctors may use a thin, flexible viewing tube (laparoscope) inserted through a small incision just below the navel, particularly if they think the cancer is not advanced. They use instruments threaded through the laparoscope, sometimes with robotic assistance, to take samples from various other tissues and to examine the ovaries and other organs. The information thus obtained can help doctors determine whether and how far the cancer has spread (its stage). The ovaries can also be removed to treat ovarian cancer using laparoscopy.
Open surgery: If doctors think the cancer may be advanced, they make an incision in the abdomen and directly view the uterus and the tissues around it. They determine the cancer's stage and remove as much of the cancer as possible.
Staging of ovarian cancer
Stages are based on how far the cancer has spread. Stages range from I (the earliest) to IV (advanced):
Stage I: The cancer occurs only in one or both ovaries (or fallopian tubes).
Stage II: The cancer has spread to the uterus, or nearby tissues within the pelvis (which contains the internal reproductive organs, bladder, and rectum).
Stage III: The cancer has spread outside the pelvis to lymph nodes or to other parts of the abdomen (such as the surface of the liver or spleen).
Stage IV: The cancer has spread outside the pelvis (for example, to the lung).
The prognosis for women with ovarian cancer is based on the stage. The percentages of women who are alive 5 years after diagnosis and treatment (5-year survival rate) are
Stage I: 85 to 95%
Stage II: 70 to 78%
Stage III: 40 to 60%
Stage IV: 15 to 20%
The prognosis is worse when the cancer is more aggressive or when surgery cannot remove all visibly abnormal tissue. Cancer recurs in about 70% of women who have had stage III or IV cancer.
Some experts believe that if ovarian or breast cancer runs in the family, women should be tested for genetic abnormalities. If first- or second-degree relatives have such cancers, particularly among Ashkenazi Jewish families, women should discuss genetic testing for BRCA abnormalities with their doctors.
Women with certain BRCA gene mutations may be offered the option of having both ovaries and fallopian tubes removed after they no longer wish to bear children, even when no cancer is present. This approach eliminates the risk of ovarian cancer and reduces the risk of breast cancer. More information is available from the National Cancer Institute Cancer Information Service (1-800-4-CANCER) and the Foundation for Women's Cancer.
Did You Know...
If women have first- or second-degree relatives with ovarian or breast cancer, they should ask their doctor about genetic testing for BRCA abnormalities.
Removal of ovaries, fallopian tubes, and uterus
Sometimes more extensive surgery (cytoreductive surgery)
The extent of surgery depends on the type of ovarian cancer and the stage.
When cancer has spread beyond the ovary, nearby lymph nodes and surrounding structures that the cancer typically spreads to are also removed. This approach aims to remove all visible cancer. If a woman has stage I cancer that affects only one ovary and she wishes to become pregnant, doctors may remove only the affected ovary and fallopian tube.
For more advanced cancers that have spread to other parts of the body, doctors usually remove as much of the cancer as possible to prolong survival. This type of surgery is called cytoreductive surgery. However, depending on where the cancer has spread, women may be treated with chemotherapy instead of or before and after surgery.
After surgery, most women with stage I epithelial carcinomas require no further treatment. For other stage I cancers or for more advanced cancers, chemotherapy may be used to destroy any small areas of cancer that may remain. Typically, chemotherapy consists of paclitaxel combined with carboplatin, given 6 times. Most women with germ cell tumors can be cured with removal of the one affected ovary and fallopian tube plus combination chemotherapy, usually with bleomycin, cisplatin, and etoposide. Radiation therapy is rarely used.
Advanced ovarian cancer usually recurs. So after chemotherapy, doctors typically measure levels of cancer markers (such as CA125). If the cancer recurs, chemotherapy is given. Many different chemotherapy drugs or combinations of drugs may be used.