Long term effects of once-only flexible sigmoidoscopy screening after 17 years of follow-up: the UK Flexible Sigmoidoscopy Screening randomised controlled trail

Autor: Atkin, WS, Wooldrage, K, Parkin, DM, Kralj-Hans, I, MacRae, E, Shah, U, Duffy, S, Cross, AJ
Přispěvatelé: Department of Health, Cancer Research UK, Medical Research Council (MRC)
Rok vydání: 2017
Předmět:
Popis: Background: This multicentre randomised trial is examining the effect of single flexible sigmoidoscopy (FS) screening on colorectal cancer (CRC) incidence and mortality. Previous analyses of this and other trials have only reported follow-up after FS for a maximum of 12 years. The objective of this analysis was to examine the long-term effects of FS after 17 years of follow-up. Methods: Between 1994 and 1999, 170,432 eligible men and women, who had indicated on a previous questionnaire that they would probably attend for screening if invited, were randomised to an intervention group (offered FS screening) or a control group (not contacted) in a 1:2 ratio. Randomisation was performed centrally in blocks of 12, and stratified by trial centre, general practice and household type. The primary outcomes were incidence and mortality of CRC. Hazard ratios (HR) and 95% confidence intervals (CI) for CRC incidence and mortality were estimated for intention-to-treat and per-protocol analyses. The trial is registered, number ISRCTN28352761. Findings: This analysis included 170,034 people (57,098 in the intervention and 112,936 in the control group). During screening and a median of 17.1 years’ follow-up, CRC was diagnosed in 1,230 individuals in the intervention and 3,253 in the control group, and 353 vs. 996 respectively died from CRC. In intention-to-treat analyses, CRC incidence was reduced by 26% (HR 0.74, 95% CI 0.70-0.80) and CRC mortality by 30% (HR 0.70, 95% CI 0.62-0.79). In per-protocol analyses, adjusted for non-compliance, CRC incidence and mortality were 35% (HR 0.65, 95% CI 0.59-0.71) and 41% (HR 0.59, 95% CI 0.49-0.70) lower in attenders. Interpretation: A single FS continues to provide substantial protection from CRC diagnosis and death, with protection lasting at least 17 years.
Databáze: OpenAIRE