Doctors use many tests to diagnose cancer and find out if it has metastasized (spread). Some tests may also determine which treatments may be the most effective. For most types of cancer, a biopsy is the only way to make a definitive diagnosis of cancer. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Imaging tests may be used to find out whether the cancer has metastasized. Your doctor may consider these factors when choosing a diagnostic test:
- Age and medical condition
- Type of cancer suspected
- Severity of symptoms
- Previous test results
In addition to a physical examination, the following tests may be used to diagnose cervical cancer:
Pap test. The doctor gently scrapes the outside of the cervix and vagina and takes samples of the cells for testing.
Improved Pap test methods have made it easier for doctors to find cancerous cells. Traditional Pap tests can be hard to read because cells can be dried out, covered with mucus or blood, or clump together on the slide.
- The liquid-based cytology test (often referred to as ThinPrep or SurePath) transfers a thin layer of cells onto a slide after removing blood or mucus from the sample. Because the sample is preserved, other tests (such as the HPV test mentioned in the Prevention section) can be done at the same time.
- Computer screening (often called AutoPap or Focal Point) uses a computer to scan the sample for abnormal cells.
Pelvic examination. In this examination, the doctor feels a woman’s uterus, vagina, ovaries, fallopian tubes, cervix, bladder, and rectum to check for any unusual changes. A Pap test is often done at the same time.
HPV typing. An HPV test is similar to a Pap test, where the test is done on a sample of cells from the patient’s cervix. The doctor may test for HPV at the same time as a Pap test or after Pap test results show abnormal changes to the cervix. Certain strains of HPV, such as HPV 16, are seen more often in women with cervical cancer and may help confirm a diagnosis. Many women have HPV but do not have cervical cancer, so HPV testing alone is not an accurate test for cervical cancer.
If the Pap test showed some abnormal cells, and the HPV test is also positive, the doctor may suggest one or more of the following diagnostic tests:
Colposcopy. The doctor may do a colposcopy to check the cervix for abnormal areas. A special instrument called a colposcope (an instrument that magnifies the cells of the cervix and vagina, similar to a microscope) is used. The colposcope gives the doctor a lighted, magnified view of the tissues of the vagina and the cervix. The colposcope is not inserted into the woman’s body and the examination is not painful, can be done in the doctor's office, and has no side effects. It can be done on pregnant women.
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 definite diagnosis. The sample removed from the biopsy is analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease). If the lesion is small, the doctor may remove all of it during the biopsy. There are several types of biopsies:
- One common method uses an instrument to pinch off small pieces of cervical tissue.
- Sometimes, the doctor wants to check an area inside the opening of the cervix that cannot be seen during a colposcopy. To do this, the doctor uses a procedure called endocervical curettage (ECC). Using a small, spoon-shaped instrument called a curette, the doctor scrapes a small amount of tissue from inside the cervical opening.
- A loop electrosurgical excision procedure (LEEP) uses an electrical current passed through a thin wire hook. The hook removes tissue for examination in the laboratory. A LEEP may also be used to remove a precancer or an early stage cancer.
- Conization (a cone biopsy) removes a cone-shaped piece of tissue from the cervix. Conization may be done as treatment to remove a precancer or an early stage cancer.
The first three procedures are usually done in the doctor's office using a local anesthetic to numb the area. There may be some bleeding and other discharge and, for some women, discomfort similar to menstrual cramps. Conization is done under a general or local anesthetic and may be done in the doctor's office or the hospital.
If the biopsy indicates that cervical cancer is present, the doctor will refer the woman to a gynecologic oncologist, who specializes in treating this type of cancer. The specialist may suggest additional tests to see if the cancer has spread beyond the cervix.
Pelvic examination. The specialist may re-examine the pelvic area while the patient is under anesthetic to see if the cancer has spread to any organs near the cervix, including the uterus, vagina, bladder, or rectum.
X-ray. An x-ray is a way to create a picture of the structures inside of the body using a small amount of radiation. An intravenous urography is a type of x-ray that is used to view the kidneys and bladder.
Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium (a special dye) is injected into a patient’s vein to provide better detail.
Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. A contrast medium may be injected into a patient’s vein to create a clearer picture.
Positron emission tomography (PET) scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive substance is injected into a patient’s body. This substance is absorbed mainly by organs and tissues that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. A scanner then detects this substance to produce images of the inside of the body.
Cystoscopy. This procedure allows the doctor to view the inside of the bladder and urethra (canal that carries urine from the bladder) with a thin, lighted, flexible tube called a cystoscope. The person may be sedated as the tube is inserted in the urethra. A cystoscopy is used to determine whether cancer has spread to the bladder.
Proctoscopy (also called a sigmoidoscopy). This procedure allows the doctor to see the colon and rectum with a thin, lighted, flexible tube called a sigmoidoscope. The person may be sedated as the tube is inserted in the rectum. A proctoscopy is used to see if the cancer has spread to the rectum.
Laparoscopy. This procedure allows the doctor to see the abdominal area with a thin, lighted, flexible tube called a laparoscope. The person may be sedated as the tube is inserted through an incision in the body.
Find more about what to expect when having common tests, procedures, and scans.
After these diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is cancer, these results also help the doctor describe the cancer; this is called staging. Learn more about the first steps to take after a diagnosis of cancer.