The impact of marital status on survival in patients with surgically treated colon cancer

The aim of this study was to investigate the relationship between marital status and disease outcome in patients with surgically treated colon cancer. Between June 2010 and December 2015, a total of 925 patients with newly diagnosed colon cancer receiving curative resection were enrolled. The effect of marital status on 5-year disease-specific survival (DSS) was calculated using Kaplan-Meier method, and was compared by log-rank tests. A Cox regression model was used to find significant independent variables and determine whether marriage had a survival benefit in patients with colon cancer, using stratified analysis. Among these patients, 749 (80.9%) were married, and 176 (19.1%) were unmarried, including 42 (4.5%) never-married, 42 (4.5%) divorced/separated, and 93 (10.1%) widowed. There was no significant difference between the married and unmarried groups in cancer stage or adjuvant treatment. Married patients had better 5-year DSS compared with unmarried patients (69.1% vs 55.9%, P < .001). Uni- and multivariate analyses also indicated that unmarried patients had worse 5-year DSS after adjusting for various confounders (adjusted HR [aHR], 1.66; 95% CI, 1.24-2.22). Further stratified analysis according to demographic variables revealed that unmarried status was a significant negative factor in patients with the following characteristics: age >65 years, female sex, well/moderately differentiated tumor, and advanced tumor-node-metastasis (TNM) stage disease (III-IV). Thus, marriage has a protective effect, and contributes to better survival in patients with surgically treated colon cancer. Additional social support for unmarried colon cancer patients may lead to improve outcomes.