Impact of colorectal cancer screening on survival after metachronous metastasis.

Background: An increasing proportion of colorectal cancer (CRC) cases in Europe are detected by screening with faecal immunochemical testing (FIT). Previous studies showed that population screening with FIT leads to a decrease in CRC incidence and to detection at an earlier stage. However, approximately twenty percent of patients with CRC without metastases at initial diagnosis still develop metachronous metastases. We investigated the association between detection mode of the primary tumor and overall survival (OS) after metachronous metastasis in patients with CRC.

Methods: Nationwide registry-based data was obtained of 794 patients who developed metachronous metastases after being diagnosed with stage I-III CRC between January and June 2015. With multivariable Cox PH regression modelling, we analyzed the (causal) association between detection mode of the primary tumor (FIT screen-detected versus non-screen-detected) and OS after metachronous metastasis while adjusting for potential confounders.

Results: Median OS and five-year OS after metachronous metastasis were significantly higher for patients with screen-detected (n = 152) vs. non-screen-detected primary tumors (n = 642): 38.3 vs. 19.2 months, and 35.4% vs. 18.8%, respectively, p < 0.0001). After adjustment for potential confounders, the association between detection mode and OS after metachronous metastasis remained significant (HR 0.70 [95% CI 0.56-0.89]).

Conclusions: Screen-detection of the primary tumor was independently associated with longer OS after metachronous metastasis. This may support the clinical utility of the population screening program and it shows the prognostic value of detection mode of the primary tumor once metachronous metastasis is diagnosed.

Competing Interests: Declaration of Competing Interest GRV reports research grants/funding paid to her institution by Servier, BMS, Bayer, Merck, PGDx, Delfi Diagnostics, Lilly, Pierre Fabre and Sirtex. GRV reports travel/accommodation fees from Servier. CP reports an advisory role for Nordic Pharma. MK reports personal travel/accommodation fees from Congress Care-Dutch oncology society (NVMO). MK reports research grants/funding paid to her institution by Amgen, Bayer, BMS, Merck-Serono, Nordic Pharma, Roche, Servier, Sirtex, and Sanofi-Aventis. MK reports honoraria paid to her institution by BMS, Nordic Pharma, and Servier. PH reports honoraria paid to her institution by Servier. All remaining authors have declared no conflicts of interest.

(Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)