Diagnosis and Grading
There are two main types of types of cancer of the cervix. The most common is Squamous cell carcinoma, which develops from flat cells that cover the outer surface of the cervix. It is estimated that Squamous cell carcinoma is responsible for 85% of all cervical cancers. The other type producing only 15% of cervical cancers is Adenocarcinoma, a variety that develops from the glandular cells that line the cervical canal, (endocervix). It is important to remember that very early stages of cervical cancer can be detected at a cellular level and treated effectively. Abnormalities can be identified using a screening procedure known as cervical smear test. A speculum is inserted into the vagina and then expanded to expose the cervix. A spatula is pressed against the neck of the womb and rotated 360 degrees to obtain a specimen of surface squamous cells. Next a cytobrush is inserted, positioned, and rotated 180 degrees just inside the cervical canal so that a specimen of glandular cells can be collected. The specimens are smeared onto glass slides and sent to a laboratory for processing. A trained cytologist examines the prepared slides with a microscope and searches for any abnormal changes within the cells. Any changes are classified as mild, moderate or severe CIN, (Cervical Intra-epithelial neoplasia), depending on their prevalence and location.
Figure 1. Performing a cervical smear test. Figure 2. Slide specimen-displaying cells
with abnormally large nuclei, CIN3.
Cervical cancer is a progressive degenerative disease so if CIN 1 is left untreated it will advance to CIN2, then CIN3, then to more invasive stage. Invasive cancer has four distinct stages depending on the degree of extension into the surrounding tissues and extra-pelvic spread. A doctor will classify the stages after performing a number of tests to determine the level of the disease. These tests may include a thorough recto-vaginal examination, a cytoscopy, blood tests, a chest X-ray, a CT scan or an intravenous pyelogram. Stage 1 is used to describe a cancer that is confined to the cervix and can further sub-divided into levels A1, A2, B1 or B2, depending on how deeply the cancer has invaded the tissue and the size of the tumor. Stage 2, (either 2A or 2B), is cancer that has spread beyond the uterus but not to the pelvic wall or the lower third of the vagina. Stage 3, (either 3A or 3B), cancers extend to the pelvic wall or the lower third of the vagina causing kidney problems. Finally at stage 4, (4A or 4B), the cancer has invaded the bladder or rectum and/or extends beyond the pelvis.
Treatment
Treatment depends on the stage of the cancer. It may include surgery, radiation, chemotherapy or a combination of any or all of the available treatments. A patient's age, desire to have children and general medical condition all play a role when planning the best treatment. For example Stage 1A may be treated with fertility maintaining surgery. Very early CIN changes are examined using a colposcopy, (large magnifying lens), and a small tissue sample, a biopsy, is taken. Depending on the biopsy result the suspicious cells on the cervix are removed by Large Loop Excision, (LLETZ). This procedure is performed under a local anaesthetic and uses a thin wire to cut approximately 6mm of tissue away from the transformation zone. Alternatively the affected areas can be destroyed by Laser Therapy, Cold Coagulation, (freezing the cells), or Diathermy, (heat treatment). After receiving treatments for CIN it is normal to have bleeding or a discharge for a few days and sexual intercourse should be avoided for 4-6 weeks to allow the cervix time to heal. Stage 1 cervical cancer is normally treated with surgery ranging from a cone biopsy to a radical hysterectomy depending on the severity of the disease. A cone biopsy is the removal of a small piece of tissue from the transformation zone of the cervix whereas a radical hysterectomy is the removal of the uterus, cervix, lymph nodes within the pelvis, and ovaries. Later stages of cancer are treated using a combination or Chemotherapy and Radiotherapy. Radiotherapy is focused on the pelvis and consists of a combination of internal and external radiation. Internal radiation treatment is called brachytherapy and involves placing tiny radioactive sources into the cervical canal and upper vagina. External beam radiation, or teletherapy, is given to the pelvis to kill the primary tumor cancer in the lymph nodes. Cervical cancer is one of the cancers most successfully treated by radiation therapy. Side effects from radiotherapy include inflammation of the vagina, bladder, and rectum resulting in diarrhoea, cystitis and abdominal pain. Also the radiation will affect the ovaries and bring about the menopause and cause infertility. Some patients loose pubic hair and suffer with nausea, loss of appetite and weight loss. Chemotherapy is the use of anti-cancer, (cytotoxic), drugs to destroy or inhibit cancer cells. It can be just one drug or several drugs, taken from a choice of about 50 different drugs available. Chemotherapy drugs work by interfering with the ability of a cancer cell to divide and reproduce itself. The affected cells become damaged and eventually die. As the drugs are carried in the blood, they can reach cancer cells all over the body. Known side effects of chemotherapy include nausea, vomiting, hair loss, and blood disorders, however they vary between individuals. Drugs used in chemotherapy cannot be targeted at specific cells so sometimes destroy normal healthy cells. Chemotherapy can be administered to women whose cancer has returned in an attempt to shrink the tumors, control pain and other symptoms so as to prolong a good quality of life.
Prevention and Cure
The best way to prevent cervical cancer is to attend regular screening sessions so cellular changes can be detected very early on in the disease. Cervical smear tests are available, at no cost, to every sexually active woman in the UK. It is recommended that a smear test be performed every 3-5 years depending on the individuals' previous medical history. Approximately 5 million cervical smear tests are carried out in the UK each year out of which 25,240 require further investigation. Of the 25,240 women that receive abnormal, CIN, results and receive the appropriate treatment during the very early stages, only a small percentage will go on to develop cervical cancer, about 3,240 women in total. It is known that in the UK 1,300 women died from cervical cancer last year, a figure that could have been substantially reduced by earlier detection of the disease. A vaccine thought to prevent cervical cancer has been developed by the Imperial Cancer Research Fund in partnership with the Cancer Research Campaign, and is currently under trial in Manchester. It is thought that the vaccines function is to boost women's immune systems making them more resistant to contracting or harbouring HPV, the virus implicated in 98% of cervical cancer cases. Other researchers and scientists are trying to develop more efficient Chemotherapy drugs. Many are trying to create new drugs that only specifically target and destroy cancerous cells and leave healthy cells undisturbed. Some researchers are studying ways of reducing other harmful side effects of Radiotherapy, such as infertility, by targeting the radiation much more precisely. At the moment the best way to avoid developing cervical cancer is to reduce as many risk factors as possible. Starting a sexual relationship in the later, rather than earlier teens and having fewer partners will contribute towards the prevention of cervical cancer. Always practicing safe sex, with a condom, would significantly reduce the opportunities to contract HPV, the primary causative virus. Maintaining a healthy lifestyle, balanced diet, correct weight, not smoking, and regular exercise also help to keep the immune system functioning effectively, so lessen the chance of cancer developing. To conclude, cervical cancer is a potentially fatal disease with a variety of devastating consequences to which we currently have no cure. Cervical cancer is also a potentially curable disease that can be prevented easily from developing at a very early stage by a simple screening test.
Reference List
Fosbery, Richard. 1997. Human Health and Disease. Cambridge University Press. Pages 4-5.
Starr, Cecie., and McMillan, Beverly. 2001. Human Biology .4th Edition. Wadsworth Group. Pages 434-441.
Mader. S, Sylvia. 2001. Biology. 7th edition. McGraw-Hill companies,Inc. Pages 152-154.
Schirge, John., and Norwitz, Errol. 2001. Obstetrics and Gynecology at a glance. Blackwell science ltd. Pages 64-65.
Wilson, Kathleen J.W., and Waugh, Anne. 1996. Ross and Wilson Anatomy and Physiology in Health and Illness. 8th edition. Churchill Livingstone. Page 437.
www.crc.org.uk 2002. The official UK Cancer research campaign website.
www.imperialcancer.co.uk 2002. The official UK imperial cancer research
website.
www.cancerhelp.org.uk 2002.
www.cancerbacup.org.uk 2002
www.cervicalcancer.uk.com 2002.
