The epidemic that wasn't.

A national cervical cancer screening program put in place by the British government in 1988 reversed the trend of rapidly increasing incidence of the disease that began in the late 1960s, but even that achievement only hints at the program's success) Projections resulting from a birth cohort analysis suggest that without screening, the annual number of diagnoses of invasive cervical cancer would have reached 11,000 in England and Wales by 2030; the annual number of deaths from the disease, 5,500. Furthermore, 3% of women now younger than 50 would have developed cervical cancer, and 2% would have died of it before reaching age 85. The annual cost of the program comes to an estimated 36,000 [pounds sterling] per life saved and 18,000 [pounds sterling] per cancer prevented. Although the national screening program has suffered what the analysts call "unjustified criticism and occasional widely publicised failures," they contend that it is "remarkably successful and ... still improving."

(1.) Peto J et al., The cervical cancer epidemic that screening has prevented in the UK, Lancet, 2004. 364(9430): 249-256.