A study was made of the later occurrence of uterine cancer among 39,756 women who were medically and cytologically examined between 1947 and 1959, cancer not having been found a t first examination. The subjects were traced for varying periods of time up to 17 years and many of them were examined repeatedly. At first examination 436 of the women had Pap smears read as class I11 or higher (cancer not being demonstrated at that time). Over 10% of them later developed uterine cancer. Some 19,000 women had smears read no higher than class I or I1 at two consecutive examinations and 24 of them developed invasive carcinoma of the cervix uteri within 3 years thereafter. At first examination about one fifth of the women reported spotting, abnormal bleeding or discharge from the vagina. The incidence rate of uterine cancer (including carcinoma in situ) was far higher among this group of women than among women who were free of the complaints when first examined; this difference persisted for over 10 years. Therefore, women with such complaints constitute a "high risk" group in relation to the later occurrence of uterine cancer. On the basis of these findings we recommend that great effort be made to persuade women in the "high risk" group to be examined annually (or once every 6 months in the case of women found to have class I11 or higher smears).
HE VALUE OF EARLY DETECTION OF UTERINE
T cancer appears to be established beyond dispute. Furthermore, it is feasible to the extent that women are willing to take the simple steps necessary for their protection-the few steps to their doctor's office. T h e question is when and how often should they do so.
For many years women have been urged: (1) to go to their doctor if they have a "cancer danger signal" and (2) to have an annual medical examination including a cytologic smear. T h e great decline in death rates from uterine cancer during the last two decades has probably been due largely to the success of this program.8 However, the disease has not yet been conquered; 13,838 American women died of it in 1965 and it is estimated that approximately 13,500 will die of it in 1968. Obviously, there remains much room for improvement. This paper is concerned with finding means for making further progress.