What is cervical cancer?
The cervix is the lower part of the uterus (womb). It is often referred to as the neck of the womb and extends into the vagina.
Among cancers affecting women, the incidence of cervical cancer in Ireland is second only to breast cancer. The latest statistics from the National Cancer Registry report that approximately 965 new cases of cervical cancer are reported in Ireland every year. On average, 85 women will die from cervical cancer every year. However, if detected early, cervical cancer can be successfully treated in almost all cases.
There are two main types of cervical cancer: squamous cell, the commonest, and adenocarcinoma. These names are based on the type of cells that have become cancerous.
Since the early 1990s the number of deaths from cervical cancer has fallen and the number of diagnosed cases of early or pre-cancer has increased. These changes are believed to be largely due to the success of the cervical screening programme, a routine test capable of identifying cervical cancer at a very early stage.
What are the risk factors?
The exact cause of cervical cancer is not known.
However, during the late 19th century, clinicians observed the low incidence of cervical cancer among nuns and began to suspect that cervical cancer may have a sexual cause. In the last few years the development of cervical cancer has been firmly linked with certain types of the human papillomavirus (HPV), a sexually transmitted virus that produces benign growths on the skin including genital warts.
It is important to realise that not all cervical cancers are associated with HPV infection and not all HPV infections result in cervical cancer. In fact, persistent infection with HPV seems to be necessary for the development of cervical cancer and usually occurs decades after the initial HPV infection. It is not known why HPV infection persists in some women but not in others. Nor is it known what determines who goes on to develop cervical cancer. A number of additional risk factors have been identified.
Risk factors for the development of cervical cancer
- Having your first experience of sexual intercourse at a young age.
- Having many sexual partners.
- Having sex with someone who has had many sexual partners.
- Having had a previous infection with other sexually transmitted diseases.
- Having had many children, especially when young.
- Smoking (women who smoke are twice as likely to develop cervical cancer than those who don't).
- Long-term use of the oral contraceptive pill (greater than 12 years).
- Deficient diets in developing nations may be a contributory factor.
Hormonal and reproductive factors may have an independent effect on the development of cervical cancer in women with HPV infection. However, there is no evidence that HRT causes cervical cancer.
Risk factors such as smoking, poor diet and the presence of other sexually transmitted infections may only have an indirect effect e.g. weaken the ability of the immune system to fight off infection.
Many women with some or all of the above risk factors never develop cervical cancer. Also, cervical cancer may occur in the absence of these risk factors.
How do I recognise the symptoms?
There are often no signs or symptoms until the cancer is quite advanced. Advanced signs include:
- Abnormal vaginal bleeding: intramenstrual bleeding (bleeding between periods); recurrence of bleeding after the menopause; bleeding after intercourse.
- Discomfort/pain during intercourse.
- Smelly vaginal discharge.
- These symptoms do not always mean that a woman has cervical cancer.
How is it diagnosed?
Cervical smear tests can pick up changes in the cervix before cancer develops or detect cancer at a very early stage. The doctor will then organise other investigations. He may repeat the cervical smear or advise you to have a colposcopy.
A woman may present to her doctor with signs of cervical cancer or abnormal cells may be identified during a smear test. The doctor may at first order a repeat smear before carrying out any futher tests.
The cervical smear test, which was introduced in the 1940s, has significantly improved detection rates and the chance of successful treatment for cervical cancer.
It is used to diagnose or screen for cancerous or pre-cancerous cells, which can then be treated before they develop into invasive cancer (cancer that has spread). They can also detect abnormal cells, referred to as cervical intra-epithelial neoplasia (CIN). The majority of women with these abnormal cervical cells will not develop cancer.
Women are advised to go for their first smear test at the age of 25 or soon after they become sexually active. They should then go for a second follow-up a year later and at 3- to 5-year intervals thereafter.
Many women worry about what is involved in having a smear test - they may feel it is embarrassing or are scared it may be painful. Really there is nothing to worry about. Smear tests are very simple procedures, which only take about 5 minutes. Admittedly you may feel a slight discomfort but the whole thing is relatively quick and painless. The test involves an internal examination using a spatula-like device called a speculum. The speculum is inserted into the vagina and cells are scraped off the cervix. These cells are then placed on a slide and viewed under a microscope.
If any abnormal cells are seen, a repeat smear is requested. If the abnormalities are confirmed treatment can be initiated at an early stage.
The smear test is prone to false-positive and false-negative results. False-positives are worrying for the woman as she has to be called back for a repeat smear following a positive result for abnormal cells during her first test. False-negatives are a real problem as the abnormal cells go undetected. For this reason it is important for women to have regular cervical smear tests from the time that they become sexually active.
The cervical smear test is available from:
- Family GP
- Maternity hospitals
- Family planning clinics
- Well-woman centres
- Some health board clinics
The first phase of a national screening programme in Ireland, which aims to reduce the incidence and death rate from cervical cancer in this country, was launched in October 2000. Phase one of the programme, which is part of the national cancer strategy, covers the Mid-Western Health Board area. Approximately 67,000 women in the 25-60 year age group will be offered screening free-of-charge at minimum intervals of five years.
Cervical cancer may also be diagnosed by means of a colposcopy. This is an internal examination whereby the cervix is coated with a special solution so the abnormal areas show up more clearly. The doctor passes a colposcope (tube with a view system that magnifies the cervix) into the vagina to view the cervix. Cervical cells can then be removed and studied under a microscope.
Abnormal areas (which might lead to cancer) visible through the colposcope can be destroyed using laser or diathermy (burning) therapy or a cone biopsy may be taken. This involves removing a cone shaped piece of the cervix. The biopsy may contain all the abnormal or cancer cells in which case further treatment is not required.
If cervical cancer is identified, further investigations are often required to establish the stage of the tumour and identify any secondary cancer deposits in other parts of the body:
- Blood tests may indicate secondary tumour deposits (metastases) in the liver.
- Ultrasound of the pelvis.
- CT scan of the pelvis.
What t reatments are available?
Treatment of cervical cancer depends on a number of things including the type, size and stage of the tumour, and the age and general health of the patient.
Treatment may involve a either of the therapies outlined below or a combination of therapies.
This is usually the first choice in for women in the early stages of the disease. In women with more advanced disease, surgery may be used to reduce the bulk of the tumour or to relieve symptoms.
A localised cervical tumour may be completely removed during colposcopy.
A hysterectomy or removal of the womb, part of the vagina and lymph nodes is the usual operation for cervical cancer. The ovaries are often left in younger women to avoid precipitating menopause. If the ovaries are removed, hormone replacement therapy (HRT) may be advised.
Mainly used to treat patients in whom cervical cancer has spread and for whom it is not possible to cure with surgery. It may also be given after surgery to reduce the risk of recurrence of the cancer.
Chemotherapy drugs are cytotoxic i.e. they kill cells. They are more likely to kill cancer cells that are dividing and multiplying rapidly rather than normal cells. Chemotherapy may be given to reduce the size of the tumour before surgery or radiotherapy. It is also used to treat women whose cancer has spread to other parts of the body or has recurred.
How can I help prevent cervical cancer?
Going for regular, routine smear tests will pick up any abnormal or pre-cancerous cells, thus reducting your risk of developing invasive cancer.
Using a condom gives some protection against contracting the strains of HPV that increase your risk of developing cervical cancer.
There is evidence to suggest that a diet high in beta-carotene, vitamin C and, to a lesser extent, vitamin A may reduce the risk of cervical cancer. Foods rich in beta-carotene include carrots, red peppers and other yellow or orange pigmented fruit and vegetables. Vitamin C rich foods include oranges and citrus fruits, tomatoes and potatoes. Meat, liver, fish, egg yolks and dairy products are all good sources of Vitamin A
A vaccine against HPV type 16 (the type most likely to contribute to the development of cervical cancer) has been developed and is undergoing trials at present. It will take time to show that this is effective in reducing the incidence of cervical cancer.
Written by Medpages Editorial Team
Last Editorial Review: 25/1/2010