What is cervical cancer?
Cervical cancer is when abnormal cells in the lining of the cervix grow uncontrollably and eventually form a growth (tumour).
If not caught early, cancer cells gradually grow into the surrounding tissues and may spread to other body areas.
The cervix
The cervix is the lower part of the womb (uterus), also called the neck of the womb. It is a small round organ and a strong muscle. It has an opening called the os. The womb and the cervix are part of the female reproductive system.
The reproductive system is made up of the:
- vulva
- vagina
- womb (uterus), including the cervix
- fallopian tubes
- ovaries
The diagram shows the position of these organs in the body.
The cervix forms a canal that connects the top of the vagina to the lower part of the womb. This is called the endocervical canal.
The cervix has 2 parts:
- ectocervix – the outer surface of the cervix
- endocervix – the inside (the canal) of the cervix
This video shows more detail about the female reproductive system.
The female reproductive system includes a number of parts. The ovaries hold the eggs which are released each month during child bearing age. They also produce sex hormones which control periods. The fallopian tubes connect the ovaries to the womb (also called the uterus).
When an egg is released it travels down the fallopian tube towards the womb. At this time, sperm from the male can pass into the fallopian tube where it may meet the egg and fertilise it. Fertilised eggs pass down the fallopian tube to the womb, which holds and protects the baby during pregnancy. The lining of the womb is called the endometrium. It thickens during the menstrual cycle ready for pregnancy. If you don’t become pregnant you have a period which is when the lining sheds.
The cervix is the lower part of the womb. It is the opening into the vagina. During a period or menstruation blood passes from the womb through the cervix and then to the vagina. The vagina also opens and expands during sexual intercourse and stretches during childbirth to allow a baby to come out.
On the outside of the body is the vulva. It is made up of two pairs of lips. Between these is the opening of the vagina. Above the vagina is the urethra: a short tube that carries urine from the bladder to outside of the body and above the urethra is the clitoris: a very sensitive area that gives sexual pleasure.
For more information about cancers that can start in the female reproductive system, go to cruk.org/cancer-types
Where cervical cancer starts
Cell types
A layer of skin-like cells covers the ectocervix on its outer surface. These cells are called squamous cells.
Glandular cells that produce mucus cover the endocervix.
The skin-like cells of the ectocervix can become cancerous, leading to squamous cell cervical cancer. This is the most common type of cervical cancer.
The glandular cells of the endocervix can also become cancerous, leading to adenocarcinoma of the cervix.
Transformation zone
The transformation zone is where the area of glandular and squamous cells meets. Most cervical cancers start here.
Cervical screening
The transformation zone is the area your doctor or nurse checks during cervical screening.
Cervical screening is not a test for cancer. It is a test to look for HPV. If HPV is found (HPV positive), further tests look for abnormal cervical cells. If left untreated, the abnormal cells might develop into cancer.
Lymph nodes
Like all other body areas, there are lymph nodes around the womb and cervix. Lymph nodes (lymph glands) are part of the lymphatic system. They:
- help to protect the body against infections
- filter, drain and circulate the tissue fluid around all body cells and tissues. This fluid is called lymph fluid
Lymph nodes are also important in cancer. The lymph fluid around the cancer drains to the nearest lymph nodes. So, if any cancer cells break away from the tumour, the first place they can go is to the nearest lymph nodes.
When you have surgery for cervical cancer, your surgeon usually takes out some lymph nodes. They send them to the laboratory to check for cancer cells.
Who gets cervical cancer?
Cervical cancer is most common in women in their early 30’s.
Trans men and non-binary people assigned female at birth can also develop cervical cancer. This can happen when they haven't had an operation to remove their womb and cervix (total hysterectomy).
The main cause of cervical cancer is long lasting (persistent) infection of certain types of the human papillomavirus (HPV). HPV is a common virus. In most people, the immune system clears the infection without any problems.
How common is cervical cancer?
Around 3,200 women are diagnosed with cervical cancer in the UK each year. That’s nearly 9 cases diagnosed every day.