Cervical screening in 20–24-year olds

Abstract

The paper by Rieck et al.1 on pages 64-71 of this issue of the Journal of Medical Screening provides the justification for continuing to invite women aged 20-24 for cervical cancer screening in Wales. The decision to screen always involves a balance between harms (including costs) and benefits, and we believe that the benefits should clearly outweigh the harms since those harmed are not necessarily the same as those who benefit from screening. With regard to cervical screening in women aged 20-24 years, we still feel that the evidence of the benefits outweighing the harms is too weak to recommend population screening.Rieck and colleagues start by reviewing the literature relating to cervical screening in women aged 20-24, with particular emphasis on the natural history of high-grade cervical lesions, and then consider the effect of screening in young women on incidence, mortality and screeninginduced morbidity. Most of the literature reviewed was published prior to the recommendation of the Advisory Committee on Cervical Screening to the Minister in 2003 and virtually all of the remainder was available to the Committee at that time. With the exception of the data from Wales collated for the first time in the Rieck et al. paper, the decision to recommend cessation of screening in women aged 20-24 was therefore based on the same evidence as that considered by Rieck and colleagues. How have the two groups come to opposite conclusions? NATURAL HISTORY OF CIN3We agreed that the available evidence suggested that between 25 and 50% of CIN3 would eventually progress to invasive cancer if not treated. We also reasoned that very little of the CIN3 detected in women aged 20-24 would progress to cervical cancer by age 25 (or even age 28). Thus a certain proportion of CIN3 detected under age 25 would regress by that age, while almost all the rest could be screendetected at age 25. Even if missed at that age (due to the imperfect sensitivity of the smear test), the lesion would still have a good chance of being detected (still as CIN3) at age 28. We have no evidence that it is better to detect CIN3 at age 22 than to detect the same lesion at age 25. By delaying the screening until age 25, women with regressive disease will avoid unnecessary treatment and anxiety, particularly for low-grade disease. EFFECTIVENESS OF CERVICAL SCREENING IN YOUNG WOMENThe research that strongly influenced the Advisory Committee's recommendation was the UK audit of cervical screening, which found a significant interaction between age and the effect of screening on the incidence of stage 1B or worse cervical cancer.2 Data from the UK screening programmes showed a much more limited effect of screening on the incidence of cervical cancer in young women than in older women.We are also aware of the various studies that have attempted to estimate the effect of screening in the UK by modelling trends in cervical cancer incidence and mortality. The earlier work of one of us (PS) suggested that the effect of screening both on incidence and mortality was gr...

Age Criteria for Cervical Screening in England: Qualitative Study of Women’s Views

“…The programme's age criteria have proved controversial (Sasieni at al. 2009;Sasieni et al 2003;Sasieni et al 2006;Rieck et al 2006;Raffle 2004). The age at which routine cervical screening should cease, including in particular whether it should be lowered to 50 years, has been much debated (Strander 2009;Rebolj et al 2009), but currently remains age 64.…”