Ovarian, Fallopian Tube, and Peritoneal Cancer: Diagnosis

Approved by the Cancer.Net Editorial Board, 08/2016

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, cancer. They do tests to learn if cancer has spread to another part of the body from where it started. If this happens, it is called metastasis. For example, imaging tests can show if the cancer has spread. Imaging tests show pictures of the inside of the body. Doctors may do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know whether an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

If your primary care doctor is suspicious that you might have ovarian, fallopian tube, or peritoneal cancer, you should see a gynecologic oncologist. A gynecologic oncologist is a doctor who specializes in treating cancers of the female reproductive system.

This section describes options for diagnosing ovarian, fallopian tube, and peritoneal cancer. Not all tests listed will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and medical condition

  • The results of earlier medical tests

Early detection and treatment is important. This is often not possible for ovarian, fallopian tube, or peritoneal cancer. There are no effective screening methods until cancer is suspected. Often, women don’t have any symptoms until the tumor is large or in later stages of the disease. About 70% of epithelial ovarian cancers are not found until the disease is in an advanced stage and has spread to other parts of the body, most commonly the abdomen.

The following tests may be used to diagnose ovarian, fallopian tube, and peritoneal cancer:

  • Abdominal-pelvic examination. Usually, the first exam is the abdominal-pelvic examination. The doctor feels the uterus, vagina, ovaries, fallopian tubes, bladder, and rectum to check for any unusual changes. Some early cancers are very small before they spread and cannot be reliably felt and detected by pelvic examination. A Pap test, usually done with a pelvic examination, is not likely to find or diagnose ovarian, fallopian tube, or peritoneal cancer. However, research advances in DNA testing may help find cells trapped in the cervix that could be studied for changes that indicate cancer elsewhere in a woman’s reproductive system. These findings are considered experimental but are a promising new method for earlier detection of these types of cancers.

  • Transvaginal ultrasound. An ultrasound wand is inserted in the vagina and aimed at the ovaries and uterus. An ultrasound uses sound waves to create a picture of the ovaries, including healthy tissues, cysts, and tumors. Researchers are studying whether this test can help with early detection of ovarian cancer.

  • Blood tests/CA-125 assay. There is a blood test that measures a substance called CA-125, a tumor marker. This marker is found in higher levels in women with ovarian cancer, fallopian tube cancer, or peritoneal cancer. Woman younger than 50 with conditions such as endometriosis, pelvic inflammatory disease, and uterine fibroids may also have an increased CA-125 level. This test is more accurate in women who have had menopause. Other tumor marker tests, such as HE4, are available, but neither of these markers have been shown to be effective for the early detection of these cancers.

  • Computed tomography (CT) scan. A CT scan creates a 3-dimensional picture of the inside of the body using x-rays taken from different angles. An x-ray is a way to create a picture of the structures inside the body using a small amount of radiation. A computer combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a patient’s vein or given as a pill to swallow. A CT scan can be used to measure the tumor’s size. While the technology of CT scanning has continued to evolve, tumors or abnormalities less than about 5 millimeters (1/5th of an inch) are difficult to see.

  • Positron emission tomography (PET) or PET-CT scan. A PET scan is usually combined with a CT scan (see above), called a PET-CT scan. However, you may hear your doctor refer to this procedure as just a PET scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive sugar substance is injected into the patient’s body. This sugar substance is taken up by cells that use the most energy. Because cancer tends to actively use energy, it absorbs more of the radioactive substance. A scanner detects this substance to produce images of the inside of the body.

  • Lower gastrointestinal (GI) series. This is a series of x-rays of the colon and rectum taken after the patient has a barium enema. This procedure delivers a special dye into the rectum and colon through the anus. The barium highlights the colon and rectum on the x-ray, making it easier to identify a tumor or abnormal area in those organs. This test may be used if the doctor is concerned that the cancer is blocking the large intestine, although a CT scan with contrast (see above) is more commonly used in these circumstances.

  • Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can be used to measure the tumor’s size. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye can be injected into a patient’s vein or given as a pill to swallow.

  • Paracentesis. This is a medical procedure that removes peritoneal fluid that has built up in a person’s abdomen. This fluid build-up may be called ascites. A sample of the fluid is examined under a microscope for signs of cancer (see below, under Biopsy).  

  • Biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope. Other tests can suggest that cancer is present, but only a biopsy can make a definitive diagnosis. A pathologist analyzes the samples(s). A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease.

Biopsies for ovarian, fallopian tube, and peritoneal cancer are often done during a first surgery. During the surgery, doctors may remove as much of the tumor as possible (see Treatment Options). A tumor sample will be analyzed by a pathologist after the surgery is over. A biopsy alone is sometimes used if the diagnosis is uncertain or if there is too much tumor to remove initially with surgery. This is usually done when chemotherapy is planned as the first treatment, with possible surgery afterward. (See Treatment Options.)

After diagnostic tests are done, your doctor will review all of the results with you. As noted above, surgery and an examination of the lymph nodes may be needed before results are complete. If the diagnosis is cancer, these test results help the doctor describe the cancer. This is called staging.

The next section in this guide is Stages. It explains the system doctors use to describe the extent of the disease. You may use the menu to choose a different section to continue reading in this guide.