Retrospective Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2017; 23(15): 2731-2742
Published online Apr 21, 2017. doi: 10.3748/wjg.v23.i15.2731
Colorectal and interval cancers of the Colorectal Cancer Screening Program in the Basque Country (Spain)
Isabel Portillo, Eunate Arana-Arri, Isabel Idigoras, Isabel Bilbao, Lorea Martínez-Indart, Luis Bujanda, Iñaki Gutierrez-Ibarluzea
Isabel Portillo, Eunate Arana-Arri, Isabel Idigoras, Isabel Bilbao, Lorea Martínez-Indart, BioCruces Health Research Institute, Plaza de Cruces, 48903 Barakaldo, Spain
Isabel Portillo, Isabel Idigoras, Isabel Bilbao, Colorectal Cancer Screening Programme, Osakidetza, Basque Health Service, 48010 Bilbao, Spain
Luis Bujanda, Department of Gastroenterology, Hospital Donostia/Instituto Biodonostia, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Universidad del País Vasco (UPV/EHU), 48940 San Sebastián, Spain
Iñaki Gutierrez-Ibarluzea, Basque Office for Health Technology Assessment, Ministry for Health, Basque Government, Donostia-San Sebastián, 01010 Vitoria-Gasteiz, Spain
Author contributions: All authors have contributed as qualified researchers in the article: Portillo I in the design and writing of the paper with Arana-Arri E, who also wrote the discussion with Gutierrez-Ibarluzea I and the statistical methodology in coordination with Martínez-Indart L, who analyzed the data and drew up the results; Idigoras I and Bilbao I registered every cancer case and reviewed all items related to quality control; Bujanda L reviewed all clinical features and contrasted the data against published articles; Gutierrez-Ibarluzea I offered feedback on all drafts in order to include an appropriate bibliography and analyze the relevance of the results to health systems to write the discussion.
Supported by The Basque Health Service, BioCruces and BioDonostia Research Institutes supported this study, since the evaluation of screening programmes such as Colorectal Cancer is a strategy included in the Health plan. Osteba (Basque Office for Health Technology Assessment of the Ministry for Health) offered the methodological support to ensure that data were aligned with the quality requirements and needs of the local health system.
Institutional review board statement: This study was approved by Carlos III Health Institute, Spanish Government.
Informed consent statement: Participants gave their consent to participate when they accepted the invitation for Colorectal Cancer Screening.
Conflict-of-interest statement: No conflicts of interest.
Data sharing statement: All data published have been previously anonymized, as is required by the Ethics Committee and authorities in the Basque Country (See attached pdf of Basque Ethics principles). Technical appendix, statistical code, and dataset available from the corresponding author at mariaisabel.portillovillares@osakidetza.eus. Participants gave informed consent for data.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Isabel Portillo, PhD, Director, Colorectal Cancer Screening Programme, Osakidetza, Basque Health Service, Gran Vía 62, 48010 Bilbao, Spain. mariaisabel.portillovillares@osakidetza.eus
Telephone: +34-944-007332 Fax: +34-944-007420
Received: December 28, 2016
Peer-review started: December 30, 2016
First decision: February 10, 2017
Revised: February 23, 2017
Accepted: March 21, 2017
Article in press: March 21, 2017
Published online: April 21, 2017
Abstract
AIM

To assess proportions, related conditions and survival of interval cancer (IC).

METHODS

The programme has a linkage with different clinical databases and cancer registers to allow suitable evaluation. This evaluation involves the detection of ICs after a negative faecal inmunochemical test (FIT), interval cancer FIT (IC-FIT) prior to a subsequent invitation, and the detection of ICs after a positive FIT and confirmatory diagnosis without colorectal cancer (CRC) detected and before the following recommended colonoscopy, IC-colonoscopy. We conducted a retrospective observational study analyzing from January 2009 to December 2015 1193602 invited people onto the Programme (participation rate of 68.6%).

RESULTS

Two thousand five hundred and eighteen cancers were diagnosed through the programme, 18 cases of IC-colonoscopy were found before the recommended follow-up (43542 colonoscopies performed) and 186 IC-FIT were identified before the following invitation of the 769200 negative FITs. There was no statistically significant relation between the predictor variables of ICs with sex, age and deprivation index, but there was relation between location and stage. Additionally, it was observed that there was less risk when the location was distal rather than proximal (OR = 0.28, 95%CI: 0.20-0.40, P < 0.0001), with no statistical significance when the location was in the rectum as opposed to proximal. When comparing the screen-detected cancers (SCs) with ICs, significant differences in survival were found (P < 0.001); being the 5-years survival for SCs 91.6% and IC-FIT 77.8%.

CONCLUSION

These findings in a Population Based CRC Screening Programme indicate the need of population-based studies that continue analyzing related factors to improve their detection and reducing harm.

Keywords: Colorectal cancer, Population Screening Programme, Interval cancer, Faecal immunochemical test, Colonoscopy, Diagnosis, Mortality, Survival

Core tip: Population based screening programmes are implemented when benefits are superior to harms and risks are acceptable to healthy population. However, programmes should continuously improve their quality and efficiency. This study shows by means of a well-accepted screening strategy that there is room for improvement and those programmes could be personalized or at least, stratified. Main results show that instead of a reduction in the cut-off points of faecal inmunochemical test, other strategies such as different follow up periods for sex, stage and previous location could be more effective and minimize risks at the same time that they increase benefits.