Are you human
Over 75% of Canadians will have one form or another of this virus in their lifetime. People come into contact with this virus through any skin-to-skin sexual contact below the waistline with fingers, mouths or other body parts – even without penetration. Condoms offer good protection against sexually transmitted infections (STIs), unwanted pregnancies and HPV in general BUT do not fully protect people from transmitting this virus because there is still direct skin-to-skin contact.
The cervix (or neck of the uterus) is the lower, narrow part of the uterus which connects to the top end of the vagina. The opening of the cervix is called the os. The cervical os allows menstrual blood to flow out from the vagina during menstruation. During pregnancy, the cervical os closes to help keep the foetus in the uterus until birth. During labour, the cervix dilates – or widens – to allow the passage of the baby from the uterus to the vagina. Approximately half the cervix length is visible with appropriate medical equipment; the remainder lies above the vagina beyond view.
The cervix is covered with a layer of skin-like cells on its outer surface, called the ‘ectocervix’. There are also glandular cells lining the inside of the cervix called the endocervix; these cells produce mucus. The skin-like cells of the ectocervix can become cancerous, leading to squamous cell cervical cancer. As well, the glandular cells of the endocervix can become cancerous, leading to an adenocarcinoma of the cervix.
The ectocervix and endocervix have a three main skin layers or zones:
The Basal Layer – cells are produced here. Older cells are pushed up towards the surface. If you contract HPV, the virus will attack the basal layer cell.
Midzone – the middle layer of cells. As cells move up from the basal layer they lose their capacity to divide making them fully mature cell.
Superficial Zone – The uppermost surface of the cervix where mature cells eventually die and shed in the normal process of skin shedding . Cervical screening takes cells from this area.
The area where cervical cells are most likely to become cancerous is called the transformation zone. This is the area just around the opening of the cervix that leads on to the endocervical canal (the narrow passageway that runs up from the cervix into the womb). The transformation zone is the area that your doctor or nurse will concentrate on during cervical screening.
The vagina is the tube extending from the outside of the body to the entrance to the womb. The skin-like cells that cover the cervix join with the skin covering the inside of the vagina; so, even if you have had your womb and cervix removed, you can still have screening samples taken from the top of the vagina.
The HPV Vaccines and Preventing Cancers
HPV causes 9 different types of cancers and genital warts. HPV vaccination is the best protection from this virus. There are benefits for people of all ages. The vaccine protects people from being affected by different types of the virus with which they have not already come into contact. If a person has cleared an HPV-related infection (genital warts or an HPV-related pre-cancer), the vaccine will help against reinfection. Furthermore, if you have a cervix, getting routine screening, whether vaccinated or not, can help detect cervical cancer.
Cervical Screening (Smear Test)
Cervical screening is NOT a test to find cancer. It is a screening test to detect abnormalities (pre-cancer) at an early stage in the cells of the cervix.
Cervical screening is the process of taking a sample of cells from your cervix, which are then examined to detect abnormalities that could develop into cancer in the future. The sample of cells is placed in a liquid so that it can be analysed in the laboratory. This process is called Liquid-Based Cytology (LBC). Screening can detect precancerous/abnormal cells. The detection and successful treatment of these cells usually prevent the occurrence of cancer. Changes in these cells are generally caused by certain types of human papillomavirus (HPV). Testing for the HPV virus itself can also be done on the same LBC sample that is examined under the microscope. For more information on HPV testing click here.
Around 1,408 new cervical cancer cases are diagnosed annually in Canada . Regular cervical screening provides a high degree of protection against developing cervical cancer. Not receiving cervical screening is one of the biggest risk factors for developing cervical cancer.
Abnormal Cervical Cells and Treatment
The cervix is covered with a layer of skin-like cells on its outer surface, called the ectocervix. The results of your cervical screening test are based on the examination of the cells from the surface of the ectocervix. The test detects whether abnormal cells are present.
Cells that are found in the cervical canal are called endocervical cells (glandular cells); these are different from the ectocervix. The transformation zone is the area from where the endocervix meets the ectocervix. This is where glandular cells normally change to squamous cells of the ectocervix. Rarely, some women have endocervix cells that are abnormal and these abnormal areas are called glandular changes.
Cervical cancer forms in the tissues of the cervix. The cervix is an organ that connects the uterus and vagina. It is usually a slow-growing cancer that may or may not have symptoms but can be prevented through regular screening (a procedure in which cells are taken from the cervix and looked at under a microscope).
Cervical cancer is not thought to be hereditary. 
99.7% of cervical cancers are caused by the persistent high risk human papillomavirus (HPV) infection which causes changes to the cervical cells. HPV is an extremely common virus; around four out of five people are exposed to the virus. Anyone who is sexually active can be infected with HPV at some time and the body’s immune system will usually clear it up. Generally, most people don’t even know they have contracted the virus.
Cervical abnormalities are caused by persistent high-risk HPV infection. These abnormal cells found through cervical screening are not cancerous but, given time (often years), they may go on to develop into cancer. However, the cells often return to normal by themselves.
The most effective method of preventing cervical cancer is through regular cervical screening which allows for the detection of any early changes of the cervix. For younger women, the HPV vaccination can help prevent seven out of ten cervical cancers (70%). Cervical cancer is largely preventable and, if caught early, survival rates are high.
If you have received an abnormal cervical screening result or if your practice nurse has visually noticed changes in your cervix, you may be invited to attend a colposcopy clinic.
Colposcopy is simply a more detailed look at the cervix. Instead of looking at the cervix with the naked eye, the person performing the colposcopy will use a special microscope to see the changes at high magnification and with good lighting. Don’t worry about the sound of this! The microscope stays outside of your body. All that is inserted is the speculum, which is the instrument the GP or practice nurse uses to see the cervix during the cervical screening. Some clinics may be equipped with video equipment so that you can watch the examination, if you wish. The examination may take a little longer than a standard cervical screening test but the colposcopist (a doctor or nurse specifically trained to undertake a colposcopy) will talk to you during the examination and tell you what is happening.
You should be looked after by the dedicated staff of the colposcopy clinic. They will understand that you may be worried and will take the time to discuss your screening result before the examination. You will be examined on a purpose-built couch. The cervix is viewed using a speculum (the instrument inserted into the vagina, which was also used when you had your cervical screening test taken) and then examined with the colposcope at low magnification (4-6X). The colposcopist will put a number of different solutions on the cervix and look for changes that indicate the presence or otherwise of changes to the cells. The medical term for cervical changes is cervical intra-epithelial neoplasia (CIN).
Read more about the tests done at colposcopy, click here.