As already stated, it aims at correcting those pathological states which have already been produced, and which if allowed to continue, may lead to symptoms of cancer.
Screening for cancer comes under this category and the two important cancers that can come under this program are:
1. Cancer of the uterine cervix.
2. Cancer of the breast.
Uterine Cervix Cancer
In many Western countries, deaths from cervical cancer have been reduced by up to 50 per cent in the past 20 years. During this time, there has been increasing awareness of the importance of early diagnosis and a concerted effort to screen for the disease using the cervical smear technique or pap test.
Cells from the cervix are examined under a microscope after they have been scraped from the lining of the cervix. Many of the cancers found by this method are localized to the surface and are called in-situ cancers. Cervical cancer, when caught at this stage, is nearly always curable (more than 95 per cent).
These tests should be done on women after the age of 40 years in symptomless cases, and in those who having abnormal vaginal bleeding or persistent vaginal discharge, even earlier. Women with abnormal cells that may represent a pre-cancer change (called dysplasia) will need to have a biopsy of the cervix.
An important and interesting study on the prevalence of cervical cancer and the role of certain environmental factors in its etiology in urban and rural population of the district of Agra was carried out from 1967 to 1970, at the Cancer Research Centre, Department of Pathology, S.N. Medical College, Agra by Dr. Usha K. Luthra. A 10 per cent sample of the total married female population of 20 years old and above, in the urban and rural areas of the Agra district was studied.
The subjects were examined clinically, and cervical smears were taken. A total of26,533 subjects were examined clinically and cytologically by the Pap test. It was found that the average annual crude prevalence rate was 210 per 100,000 women, showing that Agra was a high risk area for cervical cancers. The prevalence rate of cervical cancer in Muslims was 3.20 per 1000, being approximately half of the Hindu women, i.e. 6.62 per 1000. Women who were married at the age of 14 years and below, had more than three times the prevalence of cervical cancer than women who were married at 20 years of age and above. Prevalence rate of uterine cervical cancer being twice high in Hindu females as compared with the Muslim females, may be due to the cultural fact that Muslim males are circumcised while Hindu males are not circumcised.
Studies such as cited above, provide enough information about the prevalence of cancer in an area and the means to be employed to prevent it.