SMEAR TEST

Most cases of cancer of the cervix-the neck of the womb-could be avoided is all women had regular smear tests. This is simple procedure detects pre-cancerous conditions at an early enough stage for effective treatment.

The earliest pre-cancerous cell change in the cervix mild dysphasia. This cell change can return to normal without any treatment or it may develop into severe dysphasia or cancer-in-situ. In these potentially malignant conditions the cells lining the cervix have some of the characteristics of cancer cells. They are less likely to regress but may remain static for a long time and then progress to micro-invasive cancer. This means that the abnormalities of the lining of the cervix have broken through to the underlying tissue to a limited depth. True invasive cancer of the cervix occurs when these abnormalities have completely invaded the underlying tissue.

All the abnormal cell changes preceding invasive cancer of the cervix can be cured by removing the abnormal tissue in a minor operation. A variety of treatments are available, some of which do not even need an anesthetic.

HOW A SMEAR TEST IS DONE ?

Smear tests are usually performed by doctors or nurses as part of a vaginal examination. The cervix is at the top of the vagina which makes it difficult to see, but it can be visualized using an instrument called a speculum which is gently introduced into the vagina. The speculum is usually metal or plastic and is shaped like a duck’s bill. The two blades are about 10 cm (4 in) long and 2.5 cm (1 in) wide. When the upper and lower blades are separated the cervix can be seen without difficulty.

The smear test should be done before a bimanual examination so that the diagnostic material is not inadvertently removed. The speculum may be rinsed in water or saline to ease its entry into the vagina, but no oil should be used as this can interfere with the smear.

A smear of cells is then taken from the junction between the canal through the cervix and the part of the cervix forming the top of the vagina. This is the area most likely to develop the more common type of cervical cancer.

The smear of cells is removed with a wooden spatula, then spread on to a glass slide which is placed immediately, while still wet, in a fixative medium. The slide is later stained and examined under a microscope for any abnormal cells.

It is important to relax during this examination since any tightening of the vaginal muscles will cause discomfort and make it more difficult to insert the speculum. Some women may find the procedure a bit embarrassing but its importance as a preventive measure far outweighs any inconvenience caused.

WHY A SMEAR TEST SHOULD BE TAKEN ?

Women who have pre-cancerous changes of the cervix seldom have any signs or symptoms to alert them. A doctor may not be able to tell if there is any abnormality by simply looking at the cervix. It is therefore essential for women to have regular smear tests performed to prevent cancer developing, rather than wait for alarming symptoms to arise. The earlier an abnormal condition is found, the easier it is to treat.

Although smears are used mainly to detect and prevent the commoner type of cervical cancer, they are also helpful in the diagnosis of other conditions. For example, a few cells from cancer of the ovary or cancer of the lining of the womb (eudiometrical cancer) can sometimes be seen on a smear test. However, these cells are not always present so a smear test is not a wholly reliable means of diagnosis of either of these types of cancer.

Smear tests are also used to detect vaginal infections which cause a discharge. This method is not totally accurate but it may be used in clinics where it is impossible to do formal studies of the bacteria present in the vagina. Infections which may be diagnosed in this way included herpes, thrush and trichomonas vaginas as well as the kind of organisms present in some women fitted with a non-copper IUD.

HOW OFTEN SHOULD IT BE DONE ?

About 10 per cent of smears examined are unsatisfactory or unreliable. Women are therefore advised to have a repeat smear a year after the first one. If the second smear is normal it is sufficient to have it repeated every three to five years. But if a women develops symptoms such as a blood-stained discharge between periods, or bleeding from the vagina or after intercourse, she should see her doctor immediately as such irregularities may very rarely be due to cancer of the cervix, and this must be ruled out.

If a smear test shows any abnormality it may need to be repeated sooner than usual. It is, however, unwise to have two tests done within a month as the first may remove all the abnormal cells. The second test may then be incorrectly read as normal since the abnormal cells will not have grown yet.

TREATMENT OF AN ABNORMALITY

The treatment of pre-cancerous changes varies from hospital to hospital and patient to patient. If the changes in the cervix are the reversible condition, mild dysphasia, most doctors simply repeat the smear at six-monthly intervals to see if it has returned to normal or progressed to severe dysphasia.

If the cervical changes are more serious, such as sever dysphasia or cancer-in-situ, then the area of abnormal cells must be removed. Young women usually wish to have a little surgery as possible on the cervix, to avoid problems if they want children later on.

In some hospitals the women is seen in the out-patient clinic where the cervix can be viewed directly under a special microscope called a colposcope. The abnormal cells may be then be removed with a laser or by freezing or burning them off. In other hospitals a procedure called a ring or a cone biopsy is performed. This is done under general anesthetic and the entire area of cells surrounding the vaginal opening of the cervical canal is removed-the site where cancer is most likely to develop.

Although these minor operations cure the pre-cancerous condition, it is essential that these women continue to have routine smear tests for the rest of their lives, to ensure that there is no recurrence of the disease. A similar regime of treatment is used for older women who have completed their families. If they have other gynecological problems, such as heavy periods, a hysterectomy may be recommended.

Women with invasive cancer of the cervix are usually given a course of radiotherapy to destroy the cancer cells. A special type of hysterectomy may be performed after radiotherapy.

The earlier cancer of the cervix is detected, the more likely it is to be cured. Where it has been detected in the early stages, about 85 per cent of cases have no recurrence after treatment.