Cervical cancer, or cancer of the cervix, is cancer of the entrance to the uterus (womb). The cervix is the narrow part of the lower uterus, often referred to as the neck of the womb. Cervical cancer occurs most commonly in women over the age of 30.
The American Cancer Society estimates that 12,900 diagnoses of cervical cancer will be made by the end of 2015 in the USA. Over 4,000 women in the USA die from cervical cancer each year.
The National Health Service (NHS), UK, says that over 3,000 women are diagnosed with cervical cancer each year in the UK. According to the World Health Organization (WHO) at least 200,000 women worldwide die of cervical cancer each year. WHO adds that if the HPV vaccine is administered globally, hundreds of thousands of lives each year could eventually be saved.
Cancer research UK reported that the rate of women diagnosed with the cervical cancer in the UK has halved from 16 per 100,000 in 1988 to 8 per 100,000 - the NHS (National Health Service) Cervical Screening Programme began in 1988.
Contents of this article:
You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.
Fast facts on cervical cancer
Here are some key points about cervical cancer. More detail and supporting information is in the main article.
- There are two main types of cervical cancer: squamous cell cervical cancer and adenocarcinoma of the cervix.
- Cervical cells are most likely to become cancerous in the transformation zone, found at the opening of the cervix.
- Women can be asymptomatic during the early stages of cervical cancer.
- Cervical cancer risk factors include smoking, giving birth at a young age and having a weakened immune system.
- Experts state that cervical cancer screening should not occur more than once every 3-5 years.
- It is estimated that the majority of cervical cancer deaths would be prevented if all women underwent cervical cancer screening.
- Cervical cancer screening should begin from the age of 21, or within three years of the first sexual encounter.
- Like all cancers, there are various stages of severity to cervical cancer, numbered from 0-4.
- Treatment for cancer that is confined to the cervix has a high rate of success - around 80%-95%.
- Cervical cancer risk can be reduced through various measures, including the human papillomavirus vaccine and practicing safe sex.
What is the cervix?
The cervix is part of the female reproductive system and is often referred to as the neck of the womb.
The cervix, or the neck of the womb, and the womb are both parts of a female reproductive system. The female reproductive system consists of:
- Womb (uterus), which includes the cervix
Women have two ovaries, one on either side of the lower abdomen (pelvis). Each month one of the ovaries produces an egg. Each ovary is connected to the uterus by a tube called the Fallopian tube.
In between each menstrual period an egg travels down one of the fallopian tubes and into the uterus. They alternate - one month may be the left side, and the next month the right side. When the egg enters the womb its lining thickens in preparation; in case the egg is fertilized by a man's sperm. If fertilization does not occur the thickened lining of the uterus is shed - a period (menses) occurs.
The cervix is the opening from the uterus to the vagina. It is a tight muscle that is normally firmly shut, with a small opening to allow the sperm through and the flow from a menstrual period. During labor (childbirth) the cervix opens.
Types of cervical cancer
Ectocervix - flat cells - squamous cell cervical cancer
The ectocervix is the portion of the cervix that projects into the vagina, also known and the portio vaginalis. It is about 3 cm long and 2.5 cm wide. There are flat cells on the outer surface of the ectocervix. These fish scale-like cells can become cancerous, leading to squamous cell cervical cancer.
Squamous cells - flat cells that look like fish scales. The word comes from Latin "squama" meaning "the scale of a fish or serpent". Our outer-layer skin cells are squamous cells, as well as the passages of the respiratory and digestive tracts, and the linings of hollow internal organs.
Endocervix - glandular cells - adenocarcinoma of the cervix
The endocervix is the inside of the cervix. There are glandular cells lining the endocervix; these cells produce mucus. These glandular cells can become cancerous, leading to adenocarcinoma of the cervix.
Adenocarcinoma - any cancer that develops in the lining or inner surface of an organ.
This is where cervical cells are most likely to become cancerous. The transformation zone is located around the opening of the cervix, leading on to the endocervical canal (narrow passageway running up the cervix into the uterus). During cervical screening doctors and nurses will focus on this area.
Causes of cervical cancer
Cancer is the result of the uncontrolled division of abnormal cells. Most of the cells in our body have a set lifespan; when they die new cells are produced to replace them. Abnormal cells can have two problems:
- They do not die
- They continue dividing.
This results in an excessive accumulation of cells which eventually form a lump - a tumor. Scientists are not completely sure why cells become cancerous. However, there are some risk factors which are known to increase the risk of developing cervical cancer. These risk factors include:
HPV (human papilloma virus)
Around 70% of cervical cancer cases are estimated to be caused by HPV.
Human papilloma virus infection is a sexually transmitted virus. There are over 100 different types of HPVs - 15 types can cause cervical cancer; probably 99% of them. In addition there are a number of types which can cause genital warts. It is estimated that HPV types 16 and 18 cause about 70% of cases cervical cancer while HPV types 6 and 11 cause 90% of genital warts.
Other HPV types can cause cervical intra-epithelial neoplasia (CIN) - the growth of abnormal cells on the surface of the cervix.
Many sexual partners, becoming sexually active early
Cervical cancer-causing HPV types are nearly always transmitted as a result of sexual contact with an infected individual. Women who have had many sexual partners generally have a higher risk of becoming infected with HPV, which raises their risk of developing cervical cancer. There is also a link between becoming sexually active at a young age and a higher risk of cervical cancer.
If a woman develops cervical cancer it does not mean she had several sexual partners, or became sexually active earlier than most other females. It is just a risk factor. Women who only ever had one sexual partner can develop cervical cancer.
Smoking increases the risk of developing many cancers, including cervical cancer.
Weakened immune system
Certain genetic factors
Scientists at Albert Einstein College of Medicine of Yeshiva University found that women with certain gene variations appear to be protected against cervical cancer.
Long-term mental stress
A woman who experiences high levels of stress over a sustained period may be undermining her ability to fight off HPV and be at increased risk of developing cervical cancer it can cause, scientists at the Fox Chase Cancer Center reported.
Giving birth at a very young age
Women who gave birth before the age of 17 are significantly more likely to develop cervical cancer compared to women who had their first baby when they were aged 25 or over.
Women who have had at least three children in separate pregnancies are more likely to develop cervical cancer compared to women who never had children.
Long-term use of some common contraceptive pills slightly raises a woman's risk.
Other sexually transmitted diseases (STD)
Women who become infected with chlamydia, gonorrhea, or syphilis have a higher risk of developing cervical cancer. Scientists at the Medical University of South Carolina found that HPV infections last longer if Chlamydia also is present.
Studies in several countries have revealed that women in deprived areas have significantly higher rates of cervical cancer, compared to women who live in other areas. Studies have also found higher rates in women of working age in manual jobs, compared to women in non-manual jobs. The most likely reason is a difference in the proportion of women who have regular screening. Scientists at King's College London found that some areas in South East England had rates that were three times higher than neighboring areas.
Recent developments on cervical cancer causes from MNT news
A new study claims to provide further evidence that oral human papillomavirus infections can be transmitted via oral-to-oral and oral-to-genital routes.
In what has been deemed the "largest and most detailed genetic analysis of its kind," researchers have discovered that two thirds of healthy American adults may be infected with one or more of 109 strains of human papillomavirus.
Symptoms of cervical cancer
Often during the early stages people may experience no symptoms at all. That is why women should have regular cervical smear tests.
The most common symptoms are:
- Bleeding between periods
- Bleeding after sexual intercourse
- Bleeding in post-menopausal women
- Discomfort during sexual intercourse
- Smelly vaginal discharge
- Vaginal discharge tinged with blood
- Pelvic pain.
On page 2 we look at the tests and diagnosis of cervical cancer, and the stages of cervical cancer.