Cervical cancer in women belonging to a cytologically screened population.

Women belonging to the cytologically screened population of Stockholm in 1968 to 1974 and developing cervical cancer of stage I to IV were studied. The purpose was to find out the number of women, in whom the cancer or its preclinical stage was not detected at routine screening, and the reasons for this fact. It was found that 34 out of 177 women had never been cytologically screened. The remaining 143 women had been checked at mass screening and/or at private specialists or hospitals. In 51 screened women the cancer was not detected until the women themselves attended a doctor because of symptoms. Thus in 85 women, or 48% of the series, the cancer escaped detection at an asymptomatic stage. Errors causing a delay or interruption of the follow-up of patients with suspicious smears or colposcopic atypia were observed in 25 cases. Sixty-four patients, or 45% of all screened women, had had at least one negative smear within 4.5 years prior to discovery of the malignancy. Out of these, 53 patients had got a negative smear within 3 years. Whatever might be the true evaluation of these negative smears, their influence on the continued management of the women was important. In view of the results of this study the 4 years interval of rescreening practiced in Stockholm seems to be too long. Moreover the statement is supported, that the value of health screenings is counteracted by the fact that the people most at risk are the least likely to attend.