Survival in patients with colorectal cancer diagnosed by screening colonoscopy

Abstract

Background: In Germany, screening colonoscopy was first established in 2002 as part of the national cancer screening program.

Objective: To evaluate whether colorectal cancer (CRC) survival differs when CRC is diagnosed by screening colonoscopy (S-CRC) versus diagnostic colonoscopy (D-CRC).

Design: Long-term, retrospective, multicenter, observational study.

Setting: Study centers: 10 private gastroenterology practices in Germany.

Patients: A total of 60 patients diagnosed with CRC during screening colonoscopy and 252 patients during diagnostic colonoscopy in 2002, 2003, and 2004.

Interventions: Colonoscopy.

Main outcome measurements: Survival of patients up to December 2013.

Results: Mean (± standard deviation [SD]) follow-up time was 81.0 (± 40.1) months. Union Internationale Contre le Cancer (UICC) stages I and II were found more often in S-CRC (81.6%) compared with D-CRC (59.9%; P < .002). Kaplan-Meier analysis showed significantly reduced overall survival for patients with D-CRC (mean [± SD] 86.9 [± 3.0] months; 95% confidence interval [CI], 81.0-92.8) compared with S-CRC (mean [± SD] 107.1 [± 4.9] months; 95% CI, 97.4-116.9; P = .003). When deaths not related to CRC were excluded, survival was still shorter for D-CRC patients (mean [± SD] 89.4 [± 3.0] months; 95% CI, 83.5-95.4) compared with S-CRC (mean [± SD] 109.6 [± 4.7] months; 95% CI, 100.2-119.0; P = .004).

Limitations: Retrospective study design.

Conclusion: In this long-term, retrospective study, patients with CRC diagnosed during screening colonoscopy lived significantly longer when compared with patients with CRC diagnosed during diagnostic colonoscopy.