IMPROVED CONTROL OF INVASIVE CERVICAL-CANCER IN SWEDEN OVER 6 DECADESBY EARLIER CLINICAL DETECTION AND BETTER TREATMENT

Purpose: Cancer of the cervix uteri can be controlled by cytologic scr eening for the detection of precursor lesions, but such intervention r emains unrealistic in many countries in which this cancer is common. T he possibility of reducing mortality by earlier clinical detection, fo llowed by basic therapy, has never been properly assessed. Patients an d Methods: We compiled records of incident cases of invasive cancer of the cervix diagnosed in a defined area of Sweden from 1930 through 19 90. In a cohort of 6,044 women, we analyzed temporal trends in inciden ce and survival by clinical stage and age at diagnosis. Generalized pr oportional hazards models were used to study several factors simultane ously and quantify the overall reduction in mortality. Results: For ea ch successive stage at diagnosis, the overall risk of dying increased 2.5-fold (95% confidence interval [CI], 2.4 to 2.7). From 1930, a mark ed improvement in stage distribution wets accompanied by increasing su rvival rates in stages I and II disease. These changes largely took pl ace before the introduction of screening and external-beam radiation, The 10-year relative survival rate increased from 33% in the 1930s to approximately 55% in the 1950s and thereafter. Conclusion: Improvement s in public and professional awareness of cervical cancer resulted in diagnoses at earlier clinical stages. The rate of cure in early stages improved when basic local treatment was introduced, but only little o f the progress was attributable to the introduction of more advanced t reatment technologies. These findings offer considerable hope for a su bstantial reduction in the mortality of cervical cancer without cytolo gic screening, even in countries with limited resources. (C) 1995 by A merican Society of Clinical Oncology.