How is ovarian cancer diagnosed?
No reliable screening or early detection tests exist for ovarian cancer. The Pap test does not test for ovarian cancer; it screens for cervical cancer.
If a woman has the signs and symptoms of ovarian cancer, her doctor will probably perform a complete pelvic exam, a transvaginal or pelvic ultrasound, radiological tests, such as a transvaginal ultrasound or CT scan, and a CA-125 blood test. Used individually, these tests are not definitive; they are most effective when used in combination with each other. If a woman has a strong family history or a genetic predisposition such as a BRCA mutation, doctors may use some of these tests to monitor a woman.
Among the blood tests your doctor could order is the CA-125 blood test. CA-125 is a substance in the blood that may increase when a cancerous tumor is present; this protein is produced by ovarian cancer cells and is elevated in more than 80 percent of women with advanced ovarian cancers and in 50 percent of those with early-stage cancers. CA-125, however, is approved by the Food and Drug Administration to monitor the effectiveness of treatment for ovarian cancer and for detecting disease recurrence after treatment. The protein CA-125 exists in greater concentration in cancerous cells.
Although the CA-125 blood test is more accurate in postmenopausal women, it is not a reliable early detection test for ovarian cancer. In about 20 percent of advanced stage ovarian cancer cases and 50 percent of early stage cases, the CA-125 is not elevated even though ovarian cancer is present. As a result, doctors generally use the CA-125 blood test in combination with a transvaginal ultrasound. Because CA-125 misses half of early cancers and can be elevated by benign conditions, the National Cancer Institute does not endorse using it to screen women for ovarian cancer who are at ordinary risk or in the general population.
Read more information on CA-125.
OVA1 has also been approved by the Food and Drug Administration (FDA) for risk stratification. A woman who presents with a known tumor may have this test to determine if her surgery should be done by a gynecologist or a gynecologic oncologist – doctors who are specially trained to treat women with gynecologic cancers. The test measures the levels of five proteins in blood that change when ovarian cancer is present. However, this test has not been approved for use as an ovarian cancer screening tool, nor has it been proven to result in early detection or reduce the risk of death from this disease.
Inhibin B and Inhibin A
Granulosa cell tumors are most often detected and/or monitored via the following blood indicators: Inhibin B and Inhibin A.
A transvaginal ultrasound is a test used to examine a woman’s reproductive organs and bladder, and can often reveal if there are masses or irregularities on the surface of the ovaries and within cysts that form within the ovaries. To administer the test, the doctor inserts a probe into the woman’s vagina. The probe sends off sound waves which reflect off body structures. The waves are then received by a computer that turns them into a picture. An ultrasound alone is not an accurate way to screen for ovarian cancer.
A pelvic exam may be included as part of a woman’s regular female health exam. This exam requires the doctor to place one or two fingers into a woman’s vagina and another over her abdomen to feel the size, shape, and position of the ovaries and uterus. Ovarian cancer is rarely detected in a pelvic exam and usually in an advanced stage if it is.
Recto-vaginal Pelvic Examination (also called a bimanual exam)
This exam allows your doctor to examine the ovaries for lumps or changes in shape or size. Every woman should undergo a rectal and vaginal pelvic examination at her annual check-up with her gynecologist. A Pap test is routine in a pelvic exam but it detects cervical cancer, notovarian cancer.
The only definitive way to determine if a patient has ovarian cancer is through surgery and biopsy. Doctors will perform surgery after they obtain enough evidence from their exam and test results. If there is a suspicion from these tests that ovarian cancer might be present, the patient should seek a referral to a gynecologic oncologist before surgery occurs. Research shows that women treated by gynecologic oncologists live longer than those treated by other physicians.
The most common preliminary tests are:
- CT scan or computerized tomography: CT scans employ x-rays to take multiple cross-sectional images of the tissues and bones in the body. Doctors can analyze the images individually or use software to make a three-dimensional model of the internal organs. CT scans help define the boundaries of a cancerous tumor and show the extent of tumor spread, helping a doctor determine where to operate. CT scans also are used to monitor disease recurrence. Before undergoing a CT scan, you may receive by mouth or intravenously a contrast material that allows tissues and organs to show up more readily.
- The need for a biopsy: None of the above tests are definitive when used on their own. They are most effective when used in combination with each other. The only way to confirm the presence of ovarian cancer suspected by the tests is through a surgical biopsy of the tumor tissue.
- Surgery: If tests imply a likelihood of ovarian cancer, the doctor will likely perform a laparotomy or laparoscopy depending on what the CT shows. A laparotomy is a surgical procedure involving a long incision in the wall of the abdomen to remove fluid and tissue, such as the ovaries, fallopian tubes, uterus and connecting tissue, depending on how far the cancer has spread. More information about surgery is in the Treatment section of the website.
A doctor may also perform laparoscopic surgery to perform the biopsy and remove a small, benign cyst or early ovarian cancer and to determine the extent of spread. A laparoscope is a thin tube with a camera that allows the doctor to see and remove tissue.
If a woman has fluid inside the abdomen, a doctor before surgery may inject a needle through the abdomen wall to collect the fluid for analysis.
By looking at the cells in the tissue and fluid under a microscope, a pathologist describes the cancer as Grade 1, 2, or 3. Grade 1 is most like ovarian tissue while Grade 3 cells are more immature and more likely to metastasize.