Background: The National Comprehensive Cancer Network (NCCN) has instituted treatment guidelines for stage 2A and stages 2B and 3 extremity and superficial trunk soft tissue sarcomas (ETSTS). This study examined adherence to the NCCN guidelines and factors associated with nonadherent treatment and survival outcomes.
Methods: Patients with stage 2A and stages 2B and 3 ETSTS (n = 15,957) were categorized as undergoing adherent or nonadherent treatment based on the 2014 NCCN guidelines. Multivariate logistic regression models were used to determine factors associated with nonadherent treatment. Overall survival (OS) and disease-specific survival (DSS) were calculated, and Cox models were used to generate adjusted survival curves and hazard ratios (HRs).
Results: The findings showed that 87.2% of the patients with stage 2A disease and 58.3% of the patients with stage 2B or 3 disease received adherent treatment. Community treatment facilities and uninsured or unknown insurance status were associated with nonadherent treatment for both stage groups. Adherent treatment was associated with higher 5-year adjusted OS and DSS for stage 2A and stage 2B or 3 patients. In Cox models, nonadherent treatment was associated with worse survival for both stage 2A disease (HR, 2.31; 95% confidence interval [CI], 2.02-2.63) and stages 2B and 3 disease (HR, 1.63; 95% CI, 1.53-1.73). Increasing age and non-private insurance were associated with poorer outcomes. For stages 2B and 3 disease, treatment at a community center and African American race were associated with worse survival.
Conclusions: Adherence to NCCN guidelines is excellent for stage 2A and poor for stages 2B and 3 ETSTS. Adherent treatment was associated with improved survival outcomes, highlighting the importance of adherence to NCCN guidelines.