Marriage Has A Significant Effect On The Survival Of Surgically Treated Colon Adenocarcinoma Patients

Background:Colorectal cancer is the third most common cancer in men worldwide and the second most common cancer in women,with high incidence rate and mortality rate.The survival of this cancer is affected by many factors,such as age,sex,race,tumor site,tumor grade,lymph node status,tumor stage,tumor site,molecular pathogenesis,treatment regimen and socioeconomic status.Previous studies have demonstrated that being married at the time of diagnosis is associated with a better survival of colon cancer as well as other cancers.Whether the marriage has an effect on the mortality of patients who underwent colectomy for colon adenocarcinoma remains unknown.Objective:To compare the mortality of the unmarried patients who underwent cloectomoy for colon adenocarcinoma and that of the married patients.Methods:We identified 71,955 patients who underwent colectomy between 2004 and 2009 to treat colon adenocarcinoma from the SEER Database.We performed the univariate analysis and multivariate analysis on all-cause mortality using the Cox proportional hazards regression model,and verified all factors for the PH assumption using Therneau-Grambsch PH tests.Eight variables including age,race,sex,marriage,tumor site,tumor grade,tumor stage and lymph node rates were analyzed in the Cox model.If one or more variables did not meet the assumption,we further use the multivariate extended Cox model to evaluate the effect of marital status on all-cause mortality.The Fine-Gray competing risks model was used for colon cancer-specific mortality,with death from other causes as the competing risk.Results:In multivariate analysis with the extended Cox model,all variables were proved to be the significant independent predictor of all-cause mortality.The unmarried patients carried a 1.37-fold increased risk of all-cause mortality compared with the married patients(HR,1.37;95%CI:1.33-1.40;p<0.001),and the hazard ratio remained constant over time.The results from the multivariate Fine and Gray competing risks regression model showed that the unmarried patients had an 20.7%increased risk of cancer-specific mortality compared with the married patients(HR,1.21;95%CI,1.17-1.24;p<0.001),with significant difference.And the unmarried patients also had a higher risk of death from other causes(p<0.001),with statistically significant differences.Besides,four variables including tumor site,tumor grade,sex and TNM stage violated the PH assumption(p<0.05),their effect on all-cause mortality changed over time.Conclusions:Marriage is an independent prognosis factor for survival of surgically treated colon adenocarcinoma patients.The unmarried patients carried a significantly higher risk of all-cause mortality compared with the married patients,and this risk remained constant over time.Being unmarried was at a higher risk of death from colon adenocarcinoma as well as death from other causes.Why the married status result in more favorable OS is not totally clear yet.The lower colorectal cancer screening rate,the higher metastatic cancer rate,the lower surgery rate,the lower adjuvant chemotherapy and palliative therapy rate,high levels of distress in unmarried group may be some potential reasons.Clinicians should assess marital status and provided special treatment for the unmarried patients.To improving the receipt of treatment among unmarried patients and increase their adherence to treatment may help to prolong survival.