Cervical Screening Test
The Cervical screening test (CST) is the screening test in Australia for Cervical Cancer. The cervix is the lower part of the uterus that opens into the vagina. The CST tests for the Human Papilloma Virus (HPV) that is known to cause cervical cancer. The CST replaced the Pap Smear in Australia in December 2017. This change in cervical cancer screening will pick up more cervical cancers earlier, and means women need to have fewer examinations to take the test
There are over 100 types of HPV. The Gardasil vaccine that teenagers receive at high school (and that you can get through your GP) vaccinates against nine strains of the virus, including the high-risk strains for cervical cancer, and the strains that cause genital warts. While you get HPV from sexual activity, we don’t consider it a “sexually transmitted infection”. You can choose whether you discuss it with your partner, and you don’t need to disclose it to previous partners. If this is your first CST, having HPV doesn’t mean you or your partner have been unfaithful. It may be that the HPV has been there for many years, but we just didn’t know about it. The CST is able to tell us if a woman has one of the two highest risk forms of HPV (type 16 or 18), or if she has one of the other strains that is of intermediate risk (termed “HPV non 16/18” or “HPV Other”).
If a form of HPV is detected, the pathologist will also look at the cells of the cervix under the microscope, called Cytology. This will classify the cells as Normal, or as having Low Grade or High-Grade changes. Occasionally abnormality of the glandular cells of the cervix (the cells that line the cervical canal) are detected and need to be dealt with immediately by a gynaecologist.
Pre-cancerous changes of the cervix may not always produce symptoms. Other times they may cause abnormal discharge from the vagina, irregular bleeding or bleeding after sex. Cervical abnormalities are more common in smokers, and we encourage you to quit smoking if you are a smoker.
Your GP may refer you to a gynaecologist depending on what your CST result is, and what your previous CST result was. The gynaecologist will perform a Colposcopy examination of the cervix. This is where the cervix is examined under high powered magnification, after applying acetic acid (vinegar) and iodine.
Often a cervical biopsy is performed at the time of Colposcopy to confirm the findings on CST and coloscopy. A biopsy may be a little uncomfortable but is not typically described as “painful”, as the cells of the cervix don’t have pain receptors like your skin does.
The biopsy may confirm low grade changes - this suggest viral infection and will usually resolve spontaneously in 12 months, especially if you are young. It may confirm high grade changes; these are considered “pre-cancerous” and usually require a procedure to remove the abnormal cells. Occasionally a cancer will be diagnosed this way.
Depending on the age of the patient and the type of abnormal cells, the doctor may recommend the following treatment options:
Large Loop Excision of the Transformation Zone: In this procedure, a dome shaped segment of cervical tissue including abnormal cells is removed with diathermy (heat energy).
Cone Biopsy: In this procedure, a cone shaped segment of cervical tissue including abnormal cells is removed using either diathermy or a scalpel. This is usually done under General Anaesthetic.
Abnormal Pap Smear During Pregnancy
A CST performed during pregnancy is very safe. In case of an abnormal Pap smear, a colposcopy can be performed during pregnancy. However, further treatments are delayed until the birth of the baby.
- Video about the Cervical Screening Test (1 minute)
- A Guide To Understanding Your Cervical Screening Test Results