# Impact of socioeconomic deprivation in patients undergoing elective surgical resection for colon cancer

## TL;DR

Socioeconomic deprivation is linked to worse survival in colon cancer patients, likely due to co-morbidities and lifestyle factors rather than tumor characteristics.

## Contribution

This study identifies socioeconomic deprivation as a survival risk factor in colon cancer patients, independent of tumor factors.

## Key findings

- SED (SIMD 1) patients had lower 3-year overall and cancer-specific survival compared to SIMD 5 patients.
- SED patients had higher rates of smoking, obesity, and co-morbidities, which correlated with worse survival outcomes.
- SED was not associated with tumor factors or adjuvant chemotherapy receipt in TNM III patients.

## Abstract

Colon cancer and socioeconomic deprivation (SED) are associated with adverse outcomes. This study examined correlations between clinicopathological variables and both SED and survival in tumour node metastasis (TNM) I–III and III cohorts.

Patients undergoing elective curative resection for TNM I–III colon cancer were identified from the West of Scotland cancer registry. The primary outcome of interest was the association between SED (defined using the Scottish Index of Multiple Deprivation (SIMD); SIMD 1 = most deprived; SIMD 5 = least deprived), short-term (30- and 90-day mortality), mid-term (3-year overall (OS) and cancer-specific (CSS) survival). Secondary outcomes compared SED, the administration of adjuvant chemotherapy and significant tumour and clinical factors (overall and in TNM III patients). Multivariable analyses were conducted to correlate these findings with survival.

A total of 2264 patients were included in the study (790 TNM III). Overall, there was no significant difference between SIMD 1 and 5 in 30-day mortality (2.3 versus 1.8%, respectively; P = 0.480) and 90-day mortality (3.2 versus 2.0%, respectively; P = 0.616). OS was lower in SIMD 1 than 5 (83 versus 86%; P = 0.008), as was CSS (90 versus 92%; P = 0.024). There was no significant association between SIMD and the receipt of chemotherapy (29.4% versus 34.7%, P = 0.152) or any tumour factors. Compared with SIMD 5 patients, SIMD 1 patients had a higher American Society of Anesthesiologists (ASA) grade (P < 0.001), more current smokers (17.5 versus 4.0%; P < 0.001), an RCS Charlson Score > 3 (6.6 versus 4.3%; P < 0.001), obesity (36.0 versus 22.7%; P < 0.001), and modified Glasgow Prognostic Score (mGPS) = 2 (18.5 versus 14.2%; P = 0.007). Multivariable analysis confirmed the association with ASA (odds ratio (OR) 1.70; 95% confidence interval (c.i.) 1.31 to 2.20; P < 0.001), smoking (OR 1.59; 95% c.i. 1.24 to 2.03; P < 0.001), and body mass index (BMI) (OR 1.23; c.i. 1.01 to 1.50; P = 0.045). Similar associations were seen among TNM III patients, although SIMD 1 (versus 5) patients were less likely to commence adjuvant chemotherapy (59.4 versus 73.0%; P < 0.10).

Overall, SIMD 1 patients had worse OS in both the both TNM I–III and III cohorts, with co-morbidity and lifestyle factors most likely being responsible.

Socioeconomic deprivation is associated with host factors but not tumour factors, and this is likely the reason for adverse survival in deprived populations.