Ovarian Cancer Tests

Updated on 7/22/09

Unlike a Pap test for cervical cancer or a mammogram for breast cancer, there is currently no reliable test to screen healthy women for ovarian cancer. (A Pap test only screens for cervical cancer, not ovarian cancer.) Every woman should have a vaginal and rectal pelvic exam performed by a gynecologist, a doctor who specializes in treating diseases of the female reproductive organs, once a year. This exam allows the doctor to examine the ovaries from many sides. If your doctor feels something abnormal, further tests will be performed.

These tests may include:

• Genetic testing
• Transvaginal ultrasound (Sonogram)
• Surgical biopsy
• Pelvic examination
• CA-125 blood test
• Other imaging tests

Genetic Testing

Discuss your family history with your doctor. Tell your doctor about any previous cancers you have had such as breast or colon cancer. If you have one or more first-degree relatives (mother or sister) who have had ovarian cancer, this suggests a possible hereditary cause. If you are at high risk for ovarian cancer, your doctor will recommend additional testing, which may include genetic testing.

Blood tests are available for the BRCA1 or BRCA2 genes, which also cause breast cancer, and for genes involved in a familial colon cancer syndrome called Lynch Syndrome. In a woman believed to be at high risk for carrying one of these mutations, a blood test may help determine if she is high risk for the development of ovarian cancer (as well as breast, uterine, or colon cancer, depending on the gene). Many women find this information helpful in making important decisions about certain prevention strategies for them and their children. There are benefits and risks with genetic testing, so women should discuss them with their doctor.

Transvaginal Ultrasound (Sonogram)

In a transvaginal ultrasound, an instrument called an ultrasound scanner sends out sound waves and receives echoes as they bounce off the ovaries. These echoes create electronic pictures of the ovaries on a small television screen. Transvaginal ultrasound is done with a wand-shaped scanner that is covered with a latex or latex-free cover and inserted into the vagina. You will feel some pressure from the transducer as it is inserted. A radiologist interprets the pictures and then reports the findings to the doctor.

This test can show any growths on or near your ovaries, although doctors can't tell just from looking at the growths whether they are cancer. Unless you are having a transabdominal ultrasound performed first, you will be instructed not to drink any fluids 4 hours before the procedure. This procedure is usually performed in a clinic setting or doctor's office.

Surgical Biopsy

The only way to confirm a diagnosis of ovarian cancer is for a pathologist to look at the ovarian tissue. A sample of tissue is usually obtained during surgery. Read more about surgery in the treatment section.

Pelvic Examination

If ovarian cancer is diagnosed, the doctor will also need to check to see if the cancer has spread to other parts of the body. One step is a pelvic exam. In this test, the doctor examines the pelvic area to see if the cancer has spread to nearby organs, such as the uterus, vagina, bladder, and rectum. In the pelvic exam, the doctor inserts one or two gloved fingers into the vagina and presses on the lower abdomen with the other hand. Sometimes this exam involves placing a finger in the vagina and rectum at the same time to feel the structures deeper in the pelvis. You should tell the doctor if it hurts when your organs are touched or moved.

CA-125 Blood Test

The CA-125 blood test measures the level of a protein produced by ovarian cancer cells. The protein, CA-125, is known as a tumor marker because it is usually present at higher levels in women with ovarian cancer. CA-125 is most reliable, and most commonly used, to detect recurrent ovarian cancer in women who have been previously treated. If the CA-125 level is high before treatment, it can also be used to monitor or assess the effectiveness of chemotherapy treatment in women with ovarian cancer. Doctors generally look at the trend in the CA-125 levels over a course of time, rather than at each individual CA-125 level. These levels can help predict treatment outcomes for not only ovarian cancer, but closely related cancers such as fallopian tube cancer and primary peritoneal cancer.

Although CA-125 testing is helpful for monitoring treatment, this test alone can not diagnose ovarian cancer, nor is it effective in screening healthy women for ovarian cancer. A high level of CA-125 does not necessarily mean you have ovarian cancer; other non-cancerous conditions such as inflammatory conditions of the abdomen, recent surgery, and gynecologic conditions like fibroids, endometriosis, ectopic pregnancy or a ruptured cyst can all cause an increase in CA-125. At the same time, a low level of CA-125 does not mean you are cancer-free; not all ovarian cancer cell types produce CA-125, and some produce only low levels.

Other Imaging Tests

To learn more about the extent of disease and suggest a course of treatment, the doctor may order some of the following imaging tests:

Chest X-ray: A chest X-ray can show whether cancer has spread to the lungs.

Computerized Tomography (CT) Scan: This diagnostic test uses an X-ray machine and a computer to create detailed pictures of the body, including 3-D images. It is used to provide detailed information about the size, shape, and position of a tumor. It may also provide information on enlarged lymph nodes that may contain cancer that has spread from the ovary.

As part of a CT scan, you may be asked to drink oral contrast or have an IV line (a tube that enters a vein in the body) for injection of a contrast dye. Contrast dye makes your organs more visible on the X-ray film.

Magnetic resonance imaging (MRI): This diagnostic test uses magnetic fields and radio (sound) waves to create computerized pictures of the pelvis and abdomen. The doctor views these pictures to see whether cancer has spread. You may be placed in a tube, which may feel confining to people who have a fear of enclosed spaces. A contrast dye might be used. The MRI is noisy while it is operating, so patients usually wear earplugs.

PET scan: This test detects the energy given off by a radioactive chemical in your bloodstream. First you will have a very small dose of the chemical, called a radiotracer, injected into a vein in your arm. The tracer travels through the body and is absorbed by the organs and tissues being studied. Next, you will be asked to lie down on a flat examination table that is moved into the center of a PET scanner. This machine detects and records the energy given off by the tracer substance and, with the aid of a computer, this energy is converted into three-dimensional pictures. A physician can then look at cross-sectional images of the body organ from any angle in order to detect any functional problems.