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Colposcopy
After a woman has had an abnormal cervical/Pap smear it is necessary to examine her cervix with a special binocular microsocope - a colposcope. The woman to be examined sits on a special couch which supports her legs and a speculum is passed to visualise the cervix (just like having a smear). To identify the site, grade and shape of the abnormal area of cells, the doctor carrying out the colposcopy examination will stain the cervix in the area of the Transformation Zone (T.Z.). A solution of acetic acid (which smells like vinegar) is gently wiped on the cervix with a long 'Q' tip. Abnormal dyskaryotic/dysplastic cells will stain white and, as a generalisation, the more dense the white area becomes the higher the grade of abnormality. A water-based solution of iodine is then gently applied to the rest of the cervix to identify the complete area of abnormality. With iodine, the normal cells stain jet black and the abnormal cells stain yellow. In most cases there is good correlation between the abnormality suggested by the cervical smear and the appearances seen through the colposcope. In cases of doubt a small biopsy can be taken from the worst looking area for analysis. This is carried out using special biopsy forceps which look like a bird's beak and remove a small fragment of tissue with minimal discomfort. Women who have an obvious abnormality at colposcopy, or who have a positive biopsy result will proceed to treatment. The most common form of treatment is called LLETZ (Large Loop Excision of the Transformation Zone) in the British Isles, and LEEP (Loop Electro-Excision Procedure) elsewhere. Treatment by LLETZ can take place at the end of the colposcopy examination during the same clinic visit. This is called "See and Treat". Alternatively, treatment may be carried out at a separate, later visit. Cervical Cancer CausesThe primary risk factor for cervical cancer is infection with HPV, a sexually transmitted virus, which is present in more than 95% of cases and implicated in the cause of the disease. It is often known as the "wart" virus, as some types of HPV cause common warts that grow on feet, hands and the genital area. There are over 100 different HPV subtypes - cancer of the cervix is thought to be predominantly the result of infection with 13 key (high risk) subtypes. The majority of women infected by high risk subtypes will clear the virus spontaneously, but in a small percentage of women it persists - it is these women who need regular supervision and care. HPV types 1, 3 and 5 cause warts on the hands and feet (verrucas) of children. Types 6 and 11 can cause warts in the genital area. Most infections with HPV go away without causing any type of abnormality. The vast majority of women with HPV will not develop warts. Types 16, 18 and 31 do not cause warts, but are associated with the development of cervical precancer and cancer. The virus may lay dormant in the cervix for many years, then enter the cell nucleus and trigger a precancerous and later cancerous change. Warts and cervical precancer are encouraged by a decrease in the woman's immune system. Many researchers believe that cigarette smoking encourages cervical precancer. Concentrations of nicotine and cotinine in the cervix harms the cells. Women with HPV changes on their cervix do not require treatment unless precancerous changes (dyskaryosis/dysplasia) develop. Vaccines for HPV are being developed which may prevent cervical precancer and cancer in the future. In the meantime, all women who are, or have been, sexually active should have cervical/Pap spears at regular intervals. TreatmentTissue analysis by the pathologist divides precancerous changes into low grade or high grade squamous intraepithelial lesions (SIL). If the abnormality occupies the first third of the cervical skin it is called CIN I (cervical intraepithelial neoplasia) and two thirds CIN II. If the precancerous cells occupy full thickness it is called CIN III - the old name for this was "carcinoma in situ". For women who have CIN II, CIN III or persistant CIN I precancerous changes the most common treatment is called Large Loop Excision of the Transformation Zone (LLETZ), also called Loop Electro-Excision Procedure (LEEP). A loop of wire through which a specially blended electric current flows is used to shave off the abnormal cells. Like a tiny cheesewire, the loop cuts out the abnormal piece of skin from the cervix and seals up the area as it passes through. Any residual abnormal tissue can be destroyed by another pass of the loop or more cautery.
 Anaesthesia Many women who have the LLETZ/LEEP procedure prefer to have local anaesthesia if the operation is carried out in a warm, friendly, custom-designed outpatient suite. Women having treatment in an operating theatre, or those who are fairly nervous, may prefer to have treatment under general anaesthesia i.e. fully asleep after an intravenous injection. Those women who prefer local anaesthesia will have an injection of local anaesthetic (as used by dentists) into the cervix before the loop is passed through the cervix to remove the abnormal cells. Recovery Healing is usually very rapid and complete. The small "crater" left behind after the abnormal tissue is removed fills up quickly and normal skin grows over without delay. Usually healing is complete after two or three weeks. Following the operation there is no pain, but most women experience some discharge and/or bleeding for up to two weeks and may need to wear a sanitary towel on or off for a couple of weeks. Many doctors recommend the use of a triple sulpha antiseptic cream vaginally each night for up to a week to prevent infection setting in. Usually the cervix heals completely normally with no scarring or damage. Fertility is not affected, and because the tissue removed is relatively small there is usually no damage produced which could cause problems with subsequent pregnancy or childbirth. "See and Treat" Some doctors, especially in the public health service, offer treatment at the same time as the investigating colposcopy examination. This saves a second visit, but may leave the woman unprepared. Other doctors like to do the colposcopy examination at one visit and then plan the treatment at a second visit when the woman will not mind wearing a sanitary towel on and off for a week or two afterwards. Aftercare The use of an antiseptic cream after treatment definitely prevents infections setting in. A very small number of women will have very heavy bleeding after the operation and will need to contact their gynaecologists immediately for help. Advice varies after loop excision procedures, although many gynaecologists recommend their patients to avoid swimming, intercourse and tampons for two or three weeks after the operation. Pathology The piece which is removed from the cervix is sent for microscopic analysis by a pathologist. The pathologist will ensure that all the changes seen are not cancerous but pre-cancerous. He or she will report to the gynaecologist the grade of precancerous change found (CIN I, CIN II or CIN III) and the likelihood that all of the abnormal cells have been removed. Laser Before the introduction of the LLETZ/LEEP operation in the early 1990s, laser treatment was very popular in removing precancerous cells from the cervix. After confirming the diagnosis of CIN/SIL with a small punch biopsy, a laser beam (high-energy light) was used to vaporise the abnormal area, or the laser beam was used to cut a cone of tissue out similar to the LLETZ/LEEP procedure. Tissue healing after laser treatment was very good and a big improvement on using a surgical knife (scalpel) to cut out the abnormal tissue. However, laser treatment has largely been replaced by the LLETZ/LEEP. Whereas the equipment for LLETZ/LEEP is much cheaper to buy, use and is easier to maintain than laser generators, it is the safety aspect of sending a large amount of tissue for pathological analysis after a LLETZ/LEEP procedure to ensure that a small, invasive cancer has not been missed which attracts gynaecologists to favour LLETZ/LEEP over small biopsy/laser. Knife Cone Biopsy Occasionally, when microinvasion or early invasion is suspected, a gynaecologist will recommend that the abnormal tissue is removed using a surgical knife which may require stitches to be put into the cervix in an attempt to prevent bleeding. Long knife cones may damage the ability of the cervix to hold babies in the womb during pregnancy and a few women may rquire a big stitch (cervical suture) to be inserted in pregnancy to prevent premature delivery.
Follow-upA follow-up check after treatment for precancerous changes is absolutely essential. There is a small chance that all of the precancerous cells have not been removed completely after any form of treatment. Many gynaecologists will perform a colposcopy examination and cervical smear four to six months after treatment which begins a programme of regular surveillance thereafter. It is not common to get a new area of precancerous change several years later, but the risk of leaving precancerous cells after treatment can be up to 5% - thus it is essential that women attend all follow-up checks.
If residual precancerous cells are left behind, further treatment, such as a repeat LLETZ/LEEP procedure, will be arranged. In very special circumstances, hysterectomy (removal of the whole womb) will be advised.
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