Predictors of undergoing multivisceral resection, margin status and survival in Dutch patients with locally advanced colorectal cancer.

Background: The aim of this nationwide observational study was to evaluate factors associated with multivisceral resection (MVR), margin status and overall survival in locally advanced colorectal cancer (CRC).

Material And Methods: Patients with (y)pT4, cM0 CRC between 2006 and 2017 were selected from the Netherlands Cancer Registry. Cox-proportional hazards modelling was used for survival analysis, stratified for T4a and T4b. Annual hospital volume cut-off was 75 for colon and 40 for rectal resections.

Results: A total of 11.930 patients were included and 2410 patients (20.2%) underwent MVR. Factors associated with MVR for colon and rectal cancer besides cT4 category were more recent diagnosis (OR 3.61, CI 95% 3.06-4.25 (colon) and OR 2.72, CI 95% 1.82-4.08 (rectum)) and high hospital volume (OR 1.20, CI 95% 1.05-1.38 (colon) and OR 2.17, CI 95% 1.55-3.04 (rectum)). Patients ≥70 year were less likely to undergo MVR for colon cancer (OR 0.80, 95% CI 0.70-0.90). Risk factors for incomplete resection were cT4 (OR 3.08, CI 95% 2.35-4.04 (colon) and OR 1.82, CI 95% 1.13-2.94 (rectum)) and poor/undifferentiated tumors (OR 1.41, CI 95% 1.14-1.72 (colon) and OR 1.69, CI 95% 1.05-2.74 (rectum)). More recent diagnosis was independently associated with less incomplete resections in colon cancer (OR 0.58, CI 95% 0.40-0.76). Independent predictors of survival were age, resection margin, nodal status and adjuvant chemotherapy, but not MVR.

Conclusion: Treatment of locally advanced CRC with MVR at population level was influenced by year of diagnosis and hospital volume. Margin status in colon cancer improved substantially over time.