If you were to have asked me how I was felt prior to my first cervical smear test, I would have certainly told you I was dreading it. The concerning fact is that 1 in 4 women don’t attend regular smear tests due ideas of the procedure being “painful” and/or “embarrassing”. However, the ugly reality remains that cervical cancer accounts for 2% of all new female cancer cases in the UK [1]. Therefore, it’s vital that we continue encouraging young women to attend routine smear tests and eradicate any unknowns about how smear works.
Recent statistics suggest that nine women are diagnosed with cervical cancer every day in the UK (2016) [2]. Like with many types of cancer, cervical cancer remains asymtomatic until later stages (III/IV) of disease, hence the need for routine screening to maximise the chances of early detection of the disease. Nevertheless, it is important to be aware of the clinical symptoms of cervical cancer which include abnormal discharge, irregular bleeding and painful urination.
The smear test, or ‘pap test’ allows detection of any early cellular changes that occur in the cells the cervix and enables adequate opportunity to treat the cancer before it reaches later stages.
- Stage I where the cancer is confined to the cervix.
- Stage II at which stage the cancer has is also present upper portion of the vagina.
- Stage III where cancerous lesions may be found in the lower portion of the vagina or pelvic side wall.
- Stage IV (“Metastatic”) is when cancer has spread to to other areas of the body. Initially, cancer cells colonize nearby organs, such as the bladder or rectum, but in highly metastatic cases cancer cells can migrate as far as the lungs, liver or bones.
Nevertheless, there are different types of cervical cancer which depend upon the type of cervical cells the tumour originates from. Therefore, here’s some basic biology you really ought to be aware of.
The cervix has two main functions:
- To allow passage of sperm into the uterus
- To maintain a sterile environment within the uterus as to avoid infection, especially bacterial infection
One of the ways the cervix maintains a sterile environment is through the production of mucus which traps bacteria and expels it. In order to make mucus, some cells within the lining of the cervix are glandular which, along with the epithelial layers (“lining”) of the uterus, may become cancerous. Cancers that arises from the epithelial layers occur in 90% cases and are known referred to as squamous cell carcinoma. The remaining 10% of cervical cancer arises from the mucus-secreting glands and is referred to as an adenocarcinoma.
The majority of cervical cancers are associated with infection of the human papillomavirus (HPV), specifically HPV 16 and HPV 18 which contribute to 70% of all cases. It is estimated that 8 out of 10 people, both boys and girls, wil be infected with HPV in their lifetime however, for the majority of us, HPV infection is asymptomatic and does not cause cancer. However, it is worth noting that HPV-associated cervical cancer can take up to to 15+ years to develop. Luckily, HPV 16 and HPV 18 are routinely immunised against in conjunction with HPV 6 and HPV 11, the latter of which are associated with genital warts. Recent evidence has shown that the HPV vaccine has decreased the number of cervical cancer cases however it remains vital that we encourage women to attend their smear tests as not all cervical cancer cases are due to HPV infection. If you’re unsure on whether or not to get yourself/your child vaccinated, please do further research regarding how the HPV vaccine works.
Without rambling on about viral oncology, HPV infection is a critical step in the development of abnormal proliferative behaviour of cervical cells. This is because viruses want to replicate and do so by stimulating aberrant (“excessive”) growth or proliferation of cervical cells. The alters the morphology (“appearance”) of cervical tissue as seen down a microscope. Increased cellular division, or proliferation, increases the likelihood of developing additional “driver” mutations which ultimately lead to cancer. Ultimately, a cervical smear test is used to detect early stage abnormality in cervical cells morphology.
Figure 1 Schematic of cervical cancer progression [CRUK] Cervical cancer lesions are classified according to the cervical intraepithelial neoplasia (CIN) scale. This describes how deep into the epithelium the abnormal cells can be seen.
From start to finish, I’d estimate an appointment for a routine smear test to take 20 minutes. To those of you who have recently received your initial invitation to attend a smear test, I want to reassure you that it’s okay to be nervous, but don’t let embarrassment stop you arranging that appointment. The nurses are most likely to be very patient and should take the time to explain exactly what was going to happen. Equally, they know you’ll be nervous and it’s definitely worth asking any questions you may have. When to your reproductive health, you need to lay all your cards on the table. Whether asking questions or having headphones in makes you more relaxed, I would recommend doing so. Gynaecological health is not something to be embarrassed about.
That said, I’m off to book my next cervical smear.
References:
Image by Mohamed Hassan from Pixabay
[1] CRUK