[Interval cancers and episode sensitivity in population-based screening programmes for colorectal cancer: a systematic review]

Abstract

Objective: To describe interval cancers (IC) and the sensitivity of colorectal cancer (CRC) screening programmes.

Methods: A systematic review of the literature was conducted through a MEDLINE (PubMed) search. The search strategy combined the terms 'interval cancer', 'false negative', 'mass screening', 'screening' 'early detection of cancer', 'colorectal cancer' and 'bowel cancer'. Inclusion criteria consisted of population-based screening programmes, original articles written in English or Spanish and publication dates between 1999/01/01 and 2015/02/28. A narrative synthesis of the included articles was performed detailing the characteristics of the screening programmes, the IC rate, and the information sources used in each study.

Results: Thirteen articles were included. The episode sensitivity of CRC screening programmes ranged from 42.2% to 65.3% in programmes using the guaiac test and between 59.1% and 87.0% with the immunochemical test. We found a higher proportion of women who were diagnosed with IC and these lesions were mainly located in the proximal colon.

Conclusion: There is wide variability in the IC rate in CRC programmes. To ensure comparability between programmes, there is a need for consensus on the working definition of IC and the methods used for their identification and quantification.

Keywords: Adverse effects; Colorectal neoplasms; Cribado; Cáncer de intervalo; Efectos adversos; Interval cancer; Mass screening; Neoplasias colorrectales.