Cervical cancer

Cervical cancer occurs when abnormal cells grow uncontrollably in a woman's cervix, the lower part of the uterus, where it joins the vagina. The cervix produces lubricant for the vagina and mucus to help the motility of sperm. Human papillomovirus (HPV) is a virus transmitted by sexual activity, and is the cause of the vast majority of cases of cervical cancer. The abnormal cells in the cervix can grow to form a tumour, and in cases of advanced cervical cancer, cells can spread to other parts of the body (metastasise). Before cervical cells become cancerous, they undergo abnormal changes (dysplasia). Pap tests aim to detect these abnormal changes prior to the development of cancer. The introduction of a regular Pap test program has markedly reduced the number of women in Australia being diagnosed with cervical cancer.

Causes

The cause of cervical cancer, as with other cancers, is damage to cellular DNA. This damage results in uncontrolled cell growth, which leads to formation of a tumour. The tumours can invade nearby tissue, or cancerous cells can spread throughout the body via the bloodstream or lymphatic system. Human papillomavirus (HPV) is believed to cause most cases of cervical cancer. Importantly, the virus strains (types) involved in causing cervical cancer are different to those that cause genital warts.

Types

Squamous cell carcinoma

Squamous cell carcinoma is a type of cancer that originates in the squamous cells that cover the cervix where it is protruding into the vagina. It is the most common type of cervical cancer and is usually easily detected by a Pap test. If a Pap test is positive for changes, a colposcopy and biopsy need to be performed to confirm the diagnosis (see below).

Adenocarcinoma

This cancer is less common and originates in the glandular cells of the cervical canal. The Pap test is not as effective at picking up abnormalities that lead to this type of cancer.

Stages of cervical cancer

Treatment outcomes can vary greatly depending on the stage of cancer. Cancer is staged according to the size and location of the primary tumour and whether it has spread to nearby or distant lymph nodes, or organs throughout the body.

Different stages of cervical cancer. 

Signs and symptoms

There are usually no symptoms of the early, dysplastic changes of the cervix, and it is at this stage that a Pap test can identify presence of any abnormal cells in the cervix. When symptoms do occur, they can include:

• Vaginal bleeding in between periods;
• Pain or bleeding during sex;
• Pain or bleeding after sex;
• Vaginal bleeding after menopause;
• Abnormal vaginal discharge;
• Leg pain or swelling, and;
• Excessive tiredness.

These are also symptoms of other non-cancerous causes of these symptoms, so it is important to talk to your doctor if you are concerned.

Methods for diagnosis

Pap test

During a Pap test, some cells are scraped or brushed from the cervix and smeared onto a glass slide, which is sent to a laboratory where a cell specialist (a cytologist) checks for presence of abnormalities. As this is a screening test, it can have either a false positive or a false negative result. If there are suspicious findings from the Pap test, a colposcopy and biopsy will then be carried out to confirm the diagnosis.

Colposcopy

During a colposcopy, a magnifying instrument is used to check the cervix and vagina for abnormalities. This allows the doctor a more detailed view of the cervix. Sometimes dyes or acids are used to show up certain abnormalities.

Biopsy

One or more small tissue samples (biopsy) may be taken from the cervix during a colposcopy. These are then assessed for presence of any abnormalities.

Cone biopsy

A larger tissue sample is removed from the cervix, usually under a general anaesthetic.

Types of treatment

Surgery

Radical hysterectomy

A radical hysterectomy involves the surgical removal of the uterus, the upper part of the vagina and the lymph nodes surrounding the uterus.

Cone biopsy

Cervical cancer can be removed with a cone biopsy if it is detected early enough and if the doctor is confident the entire tumour can be removed by this technique.

Therapy

Chemotherapy

Chemotherapy works by attacking cancer cells and stopping their reproduction. Various medications are used, which can be administered intravenously or orally.

There are three general types of chemotherapy:

• Adjuvant chemotherapy, which is given after surgery with the aim of preventing recurrence of cancer;
• Neoadjuvant chemotherapy, which is given before surgery to help shrink the tumour prior to removal, and;
• Chemotherapy for advanced cancer, which uses combinations of medication that are administered in cycles followed by a rest period.

Side effects occur because chemotherapy can also affect the reproduction of healthy cells. Your doctor will monitor your dosage carefully to ensure an optimal therapeutic dosage is achieved.

Chemotherapy medication is effective in destroying cancerous cells. 

Radiotherapy

In this type of therapy, focused X-rays are applied to the area where the tumour is located. Another form of radiation therapy is brachytherapy. This involves inserting a small, radioactive implant in the tumour or the nearby area, which delivers cell-destroying radiation directly into the tumour. Radiotherapy can be used alone, or in addition to surgery and/or chemotherapy.

Other

Some people diagnosed with cancer seek out complementary and alternative therapies. None of these alternative therapies are proven to cure cancer, but some can help people feel better when used together with conventional medical treatment. It is important to discuss any treatments with your doctor before starting them since some complementary treatments can cause harm or interfere when combined with conventional cancer treatment.

Potential complications

Treatment side effects

Early menopause

The surgical removal of the ovaries, or damage to them during radiotherapy, can result in early menopause.

Narrowing of the vagina

Radiotherapy can narrow the vagina, making sex uncomfortable or painful. There are treatments available that may help to alleviate these symptoms.

Lymphoedema

The lymphatic system drains excess body fluid. Surgical removal of the lymph nodes can result in a build-up of fluid which can cause swelling. Massage and compression clothing can help relieve this swelling.

Other treatment side effects include:

• Nausea, vomiting and fatigue from chemotherapy and radiotherapy. Whether or not the treatment makes you feel sick is not an indication of how well the treatment is working;
• Altered bowel habits - constipation frequently occurs during chemotherapy, probably as a result of anti-nausea or some pain relief medication. Radiotherapy has the opposite effect, frequently causing diarrhoea;
• Joint and muscle pain may occur after a treatment session and can last a few days;
• Temporary hair loss on the head and body from some types of chemotherapy. It will grow back after treatment has ended, and;
• Tingling in the hands and feet - some chemotherapeutic agents can affect the nerves. It is important to tell your doctor if you develop these symptoms.

Complications of advanced cervical cancer

Metastasis

Metastasis is the spread of cancer to other parts of the body through the bloodstream and lymphatic system. The growth of cancer in the organs and other body parts results in a destructive effect on their function.

Kidney failure

The kidneys are the waste removal centres of the body. In some cases of cervical cancer, the tumour can exert pressure on the tubes through which the urine flows from the kidneys to the bladder (ureters). The resulting build-up of urine in the kidneys (hydronephrosis) can lead to kidney failure. Surgery can be carried out to widen the ureters or to insert drainage channels for the urine.

Blood clots

As with other cancers, cervical cancer can result in blood being more likely to form clots in the veins. Anticoagulant medications are used to reduce the risk of clots forming. Clots in the veins of the leg or pelvis can separate from the wall of the vein and then can block the of the arteries in the lungs. This is called a pulmonary embolism, a potentially life threatening condition.

Bleeding

Bleeding may occur when the cancer spreads and damages the vagina, bladder or bowel. Radiotherapy and certain medications can be used to alleviate the bleeding.

Fistula

Fistulas are abnormal passages that, in cervical cancer, usually form between the bladder and vagina or between the vagina and bowel. They can lead to the discharge of urine or faeces from the vagina. Surgery is required to correct the fistula, but isn't always possible, in which case certain medications may be used.

Prognosis

If diagnosed early, cervical cancer is curable. The relative five-year survival rate in Australia as of 2010 is 72%. For those who survive the first year, the survival rate increases to 82% and for those who survive the first five years, the survival rate increases to 95% for the next five years.

Five-year survival rates are calculated on people who were treated in the preceding five years. Advances in treatment since then might result in better outcomes for people with cervical cancer today.

Prevention

The most important thing to do is to have regular Pap tests and follow the recommendations of your doctor in case of an abnormal result. The human papillomavirus (HPV) vaccine, given prior to having sex for the first time, is very effective at reducing rates of the common types of HPV. However, since it is not effective against all strains of the HPV, regular Pap tests are still recommended. Using condoms and limiting the number of sexual partners you have will also reduce the risk of exposure to the different strains of HPV.