Surgical Compliance and Outcomes in Gastric Cancer: a population-based cohort study

Background: Surgical resection is one of curative treatment for gastric cancer (GC), however, a set of patients show poor surgical compliance in the USA.We aimed to identify the risk factors associated with surgical compliance and investigate the difference in survival.Methods: GC patients diagnosed between 1973 and 2014 were identified from the Surveillance Epidemiology and End Results (SEER) databases.Based on different surgical compliance and treatment regimen, patients were classified into three subgroups: surgical compliance group, surgical noncompliance group, and non-surgical group.Multivariable Logistic regression analysis was adopted to identify the factors related to surgical compliance; Multivariable Cox regression was used to investigate the prognostic factors.Overall survival (OS) and cancer-specific survival (CSS) were analyzed using the Kaplan-Meier estimator method.Results: Of 79374 GC patients who were recommended for surgical therapy, 15201(19.2%)cases did not perform surgery.Poor compliance of surgery was related to old age, American Indian/Alaska Native race, poor grading/late staging, single/widowed status, lower socioeconomic status and earlier time of diagnosis.As expected, GC patients of surgical compliance group showed significantly more favorable survival than the other two groups (P<0.0001);notably, the outcome of surgical noncompliance group came close to that of non-surgical group.Conclusion: GC patients of poor surgical compliance demonstrated adverse survival, which was comparable to that of non-surgical patients.The poor surgical compliance was associated with older age, American Indian/Alaska Native race, poor tissue differentiation/advanced stage of tumor, single/widowed status, lower socioeconomic status and earlier time of diagnosis.