To diagnose ovarian cancer, a healthcare provider may start with a pelvic exam to check for fluid buildup or abnormal lumps near the ovaries. In some cases, a colonoscopy may also be used if there’s reason to believe the cancer has spread.

You may be referred to a gynecologic oncologist (GYO), a specialist in reproductive system cancers. This specialist will order further tests and procedures to confirm the diagnosis and determine the stage of the disease.

Ovarian cancer affects approximately 1.1% of people with ovaries over their lifetime. Currently, there is no reliable screening method for ovarian cancer in those without symptoms.

Medical History

Your provider will ask about personal and family medical history to assess your risk. Be sure to mention if anyone in your family has had ovarian or breast cancer, as these may have hereditary links. You will also be asked about any symptoms you're experiencing, when they began, and how often they occur.

Pelvic Exam

During a pelvic exam, a provider checks for signs of ovarian cancer by feeling for lumps or fluid buildup. The provider places one or two gloved fingers inside the vagina and presses on the abdomen with the other hand to examine the size and shape of the ovaries and uterus.

While helpful, pelvic exams rarely detect early-stage ovarian cancer, as most tumors are too small to be felt.

Imaging

Imaging tests use energy like sound waves or X-rays to produce internal images of the body. These tests can reveal tumors on the ovaries, fallopian tubes, or nearby structures like the peritoneum (the lining of the abdomen).

Transvaginal ultrasound

A probe inserted into the vagina uses sound waves to produce clear images of the ovaries and uterus. It can detect a mass and help determine if it’s fluid-filled or solid. It can also reveal the presence of pelvic fluid, often seen in advanced cases.

CT scan

A computed tomography (CT) scan uses X-rays to create cross-sectional images. It’s helpful for assessing whether the cancer has spread to organs like the liver, lymph nodes, or intestines. CT scans are also used to guide biopsy procedures by helping place the needle accurately into a mass.

MRI scan

Magnetic resonance imaging (MRI) uses strong magnets to create detailed images. MRIs are not usually the first imaging test due to insurance or availability, but they can provide additional clarity when other tests have already identified a mass. MRIs can also detect cancer spread to the brain or spine.

Blood Tests

Blood tests evaluate overall health and organ function and can measure tumor markers that may be present in certain types of ovarian cancer.

CA-125 test

This test measures levels of a protein called CA-125. Elevated levels may be present in half of early-stage cases and over 90% of advanced-stage ovarian cancers. However, CA-125 can also be high in non-cancerous conditions like endometriosis or uterine fibroids, so it is not a standalone diagnostic tool.

The CA-125 test is also useful for monitoring treatment response and checking for recurrence.

Other tumor markers

Your provider may check for additional tumor markers in the blood to help identify the type of ovarian cancer:

  • Alpha-fetoprotein (AFP)

  • Human chorionic gonadotropin (hCG)

  • Inhibin

  • Lactate dehydrogenase (LDH)

Elevated levels of these markers can support diagnosis and guide treatment planning.

Surgical Biopsy

A biopsy, which involves removing a tissue sample for lab testing, is the only definitive way to diagnose cancer. Most often, a biopsy is done during surgery when a tumor is being removed. A pathologist then examines the tissue under a microscope for cancer cells.

Paracentesis

For patients with ascites (fluid buildup in the abdomen), a paracentesis may be performed. A needle is used to draw fluid from the abdomen, and the sample is tested in a lab for cancer cells. This may be done when surgery is not immediately possible.

Laparoscopy

A laparoscopy is a minimally invasive procedure in which a camera-equipped tube is inserted into a small incision in the abdomen. This allows the provider to view the abdominal cavity and take tissue samples if necessary. It’s especially useful for identifying masses that may not be visible through external imaging.

Colonoscopy

While typically used for detecting colorectal cancer, a colonoscopy can help detect whether ovarian cancer has spread to the colon or rectum. During the procedure, a flexible tube with a camera is inserted into the colon to search for abnormal tissue, and samples can be taken for testing.

Genetic Testing

If you are diagnosed with ovarian cancer, your provider may recommend genetic testing. This test looks for inherited mutations like BRCA1 or BRCA2, which are associated with higher risks for ovarian and breast cancer.

Samples are usually collected from blood, saliva, or cheek cells. Results from genetic testing can guide treatment decisions and also help family members understand their risk.

Stages of Ovarian Cancer

Once ovarian cancer is confirmed, the provider will determine its stage, which describes the tumor’s size and how far it has spread. This staging helps develop an appropriate treatment plan.

  • Stage 1: Cancer is limited to the ovaries or fallopian tubes

  • Stage 2: Cancer has spread to pelvic organs, like the uterus

  • Stage 3: Cancer has spread to the abdominal cavity or lymph nodes

  • Stage 4: Cancer has spread to distant organs like the liver, lungs, or spleen

Screening for Related Conditions

The symptoms of ovarian cancer—such as bloating, pelvic pain, and frequent urination—are similar to other conditions. To make an accurate diagnosis, providers may conduct tests to rule out:

  • Colon cancer

  • Ectopic pregnancy

  • Endometriosis

  • Irritable bowel syndrome (IBS)

  • Ovarian cysts

  • Urinary tract infections

  • Uterine fibroids

People with ovarian cancer, especially those with hereditary gene mutations, may also face a higher risk of breast cancer. Discuss additional screening strategies with your provider, such as more frequent mammograms or preventive medications.

A Quick Review

Diagnosing ovarian cancer involves a combination of methods, including pelvic exams, imaging, blood tests, and tissue biopsies. Early symptoms are often vague and similar to those of other health conditions, making accurate diagnosis essential.

If diagnosed, your provider will determine the cancer’s type and stage and create a personalized treatment plan. Early detection and coordinated care can improve outcomes and support long-term management.