During the process of diagnosing ovarian cancer, doctors will use several tests to learn more about the tumor. The first test that doctors usually recommend is an ultrasound. This painless imaging test helps doctors see what the inside of the abdomen looks like. Doctors can use ultrasounds to detect various problems with the ovaries and nearby organs.

How Do Ultrasounds Work?

An ultrasound machine uses a small handheld tool called a transducer to send sound waves into the body. These sound waves are painless and are so high-pitched that humans can’t hear them. Echoes of the sound waves bounce back to the transducer, and the machine converts the sound waves into an image. The result is a sonogram — a picture of the tissues and organs within a particular part of the body.

There are a couple of types of ultrasound. When diagnosing potential cases of ovarian cancer, doctors often use a transvaginal ultrasound, in which a probe is placed into the vagina. Doctors may also perform a pelvic ultrasound, in which the transducer is placed on the skin of the lower part of the abdomen. Both of these approaches can capture pictures of the ovaries and uterus.

What Does the Ovary Look Like on an Ultrasound?

Sonograms from an ultrasound test can show several features of the ovary. They allow doctors to see the size and shape of the ovary. A sonogram can also look at the texture of the outer surface of the ovary. Additionally, ultrasound imaging can detect abnormalities or masses on the ovary, which may or may not be cancerous.

The Normal Ovary on an Ultrasound

In general, the ovaries appear as almond-shaped structures on either side of the uterus. In individuals who have given birth multiple times, the ovaries may have moved slightly from their original position. The ovaries also shrink after menopause, so an ultrasound may not be able to detect them in older people.

For individuals who have not yet gone through menopause and are still getting their period, their ovary will contain follicles. Ovarian follicles are small sacs. Each one contains an egg cell. Follicles develop and grow larger throughout the beginning phase of the menstrual cycle. Then, a single follicle will continue to grow until it releases an egg, called ovulation.

On an ultrasound, the follicles may appear as small, dark, round shapes around the edge of the ovary. Follicles may be different sizes depending on where a person is within their menstrual cycle.

Cysts on an Ultrasound

Sometimes, an ultrasound may detect other more unusual features within an ovary. Most of these findings are not cancerous, and many are not harmful

A common ultrasound finding is a cyst (a fluid-filled sac). About 8 percent to 18 percent of women have cysts on their ovaries. Occasionally, ovarian cancer may appear as a cyst. However, ovarian cysts are usually benign (noncancerous). Often, cysts develop when a follicle fails to release an egg or fails to disappear after ovulation. These cysts usually go away over time. Occasionally, cysts are caused when blood or tissue from the uterus attaches to the ovary, called endometriomas. Cysts can also be teratomas — masses that form when an egg cell begins growing within the follicle.

Like follicles, cysts usually appear round and black on an ultrasound. They often have thin walls and don’t look like they contain anything inside. However, they are often larger than normal follicles.

Cysts don’t usually need any treatment and are often not a cause for concern. In some cases, doctors may recommend a follow-up ultrasound a few months later to see if the cyst has grown.

Ovarian Cancer on an Ultrasound

In rare cases, ovarian cysts or solid masses may be malignant (cancerous). The ultrasound doesn’t show for sure whether an abnormality is cancer, but it can provide clues. Malignant cysts and masses usually look a little different on an ultrasound. They may:

• Be very large
• Have papillary structures (bulges) on their outer or inner surface
• Be divided into multiple segments called loculations
• Contain blood or other material inside them, making them not look solid black all the way through

Some cases of ovarian cancer begin in the fallopian tubes (the tubes that connect the ovaries to the uterus). Fallopian tubes are usually invisible on an ultrasound. However, if there is a problem with the fallopian tube, it may appear as a long, thin mass. This may happen when the fallopian tube grows larger or fills with fluid due to conditions like a blockage, pelvic inflammatory disease, or cancer.

Doctors consider other information when deciding how likely it is that a cyst or mass is malignant. Risk factors that help indicate whether an abnormality is malignant include:

• Your age
• Whether you have gone through menopause
• Levels of CA-125 (a protein that can serve as a sign of ovarian cancer)
• How big the mass is
• How much solid tissue is inside of the mass, as opposed to fluid
• How many bulges or projections a mass contains
• How many masses are present
• Whether you have ascites (fluid in your abdomen)

If these factors indicate that you may have a malignancy, your doctor may recommend additional diagnostic tests or surgery to get a better look.

What Don’t Ultrasounds Tell You?

Although ultrasounds have several very useful purposes, they also have limitations. Doctors rely on additional diagnostic tests to gather more information about problems with the ovaries.

Whether You Have Cancer

Ultrasounds can detect abnormalities, and they can provide a clue as to whether an ovarian mass or cyst might be cancerous. However, biopsies are the only way to tell for sure whether a mass contains cancer cells.

For people with ovarian cancer, a biopsy is usually taken during surgery. Biopsies of the ovary are not usually performed before surgery because a needle biopsy of the ovary might potentially release cancer cells that were otherwise contained. The surgeon will send pieces of the mass to a laboratory where the cells will be studied under a microscope to determine whether they are cancerous. Biopsies also help determine the type of ovarian cancer.

Whether Ovarian Cancer Has Spread

The later the ovarian cancer stage is, the farther cancer cells have metastasized (spread within the body). Determining cancer’s stage is important for determining the prognosis (outlook) and knowing which treatment plan may be best.

Doctors don’t use ultrasounds to tell how far ovarian cancer cells have spread. Ultrasounds can’t distinguish whether cells are cancerous or not, and they are only used to look at one part of the body at a time. In order to determine cancer stage and locate metastases, doctors use other imaging tests or procedures. These other tests, which are often better at detecting cancer cells and show larger areas of the body, include:

• Magnetic resonance imaging (MRI)
• Computed tomography (CT) scan
• Positron emission tomography (PET) scan
• Surgery

Ultrasounds and Cancer Screening

Ultrasounds can be used to detect potential ovarian tumors. Does this mean that this test can help screen people for ovarian cancer?

Researchers have studied whether a transvaginal ultrasound helps detect ovarian cancer during its early stages. They have also studied whether adding blood tests to measure CA-125 levels helps improve ultrasound screening. However, the results were not promising. These tests often pick up benign, noncancerous conditions, which means that individuals who use these screening methods often undergo additional and sometimes unnecessary tests and surgeries. Additionally, ultrasound and CA-125 screenings don’t seem to reduce the overall number of people who die from ovarian cancer.

Experts say that individuals who have an average risk of developing ovarian cancer should not be screened using the currently available methods. However, some doctors recommend regular screening for those with a high risk of ovarian cancer. This includes women who have many family members who have had ovarian or breast cancer or women with genetic mutations in high-risk genes such as BRCA1 or BRCA2.

Talk With Others Who Understand

MyOvarianCancerTeam is the social network for people with ovarian cancer. More than 3,000 members come together to ask questions, give advice, and share their stories with others who understand life with ovarian cancer.

Are you living with ovarian cancer? Have you had to get an ultrasound test? Start a conversation by posting on MyOvarianCancerTeam.