The Relationship Between Co-morbidity, Screen-Detection and Outcome in Patients Undergoing Resection for Colorectal Cancer.

BACKGROUND

Bowel cancer screening increases early stage disease detection and reduces cancer-specific mortality. We assessed the relationship between co-morbidity, screen-detection and survival in colorectal cancer.

METHODS

A retrospective, observational cohort study compared screen-detected (SD) and non-screen-detected (NSD) patients undergoing potentially curative resection (April 2009-March 2011). Co-morbidity was quantified using ASA, Lee and Charlson Indices. Systemic inflammatory response was measured using the neutrophil lymphocyte ratio (NLR). Covariables were compared using crosstabulation and the χ2 test for linear trend. Survival was analysed using Cox Regression.

RESULTS

Of 770 patients, 331 had SD- and 439 NSD-disease. A lower proportion of SD patients had a high ASA (≥3) compared to NSD (27.2% vs 37.3%; p = 0.007). There was no significant difference in the proportion of patients with a high (≥2) Lee Index (16.3% SD vs 21.9% NSD; p = 0.054) or high (≥3) Charlson Index (22.7% SD vs 26.9% NSD; p = 0.181). On univariate analysis, NSD (HR 2.182 (1.594-2.989;p < 0.001)), emergency presentation (HR 3.390 (2.401-4.788; p < 0.001)), advanced UICC-TNM (III or IV) (p < 0.001), high ASA (≥3) (HR 1.857 (1.362-2.532; p < 0.001)), high Charlson Index (≥3) (HR 1.800 (1.333-2.432; p < 0.001)) and high (≥3) NLR (HR 1.825 (1.363-2.442; p < 0.001)) were associated with poorer overall survival (OS). NSD predicted poorer cancer-specific survival (CSS) (HR 2.763 (1.776-4.298; p < 0.001)). On multivariate analysis, NSD retained significance as an independent predictor of poorer OS (HR 1.796 (1.224-2.635; p = 0.003)) and CSS (HR 1.924 (1.193-3.102; p = 0.007)).

CONCLUSIONS

Patients with SD cancers have significantly lower ASA scores. After adjusting for ASA, co-morbidity and a broad range of covariables, SD patients retain significantly better OS and CSS.