Treatment Outcomes and Risk Factors for Incomplete Treatment after Definitive Chemoradiotherapy for Non-Resectable or Metastatic Esophageal Cancer

SIMPLE SUMMARY: The rates of adverse events and incomplete treatment remain high among patients with unresectable or metastatic esophageal cancer who receive definitive treatment. The overall survival and treatment-related adverse events were analyzed. Subgroup analysis was performed based on the completeness of the treatment plan. Complete treatment was positively correlated with increased survival. In multivariable analysis, poor performance, bone metastasis, airway invasion, and liver cirrhosis are risk factors for incomplete treatment. ABSTRACT: Among patients with unresectable or metastatic esophageal cancer who receive definitive chemotherapy or chemoradiotherapy, the rates of treatment-related adverse events and incomplete treatment remain high. We conducted this study to investigate survival after definitive treatments and identify predicting factors for incomplete treatment. The data of patients who received definitive chemotherapy or chemoradiotherapy for esophageal cancer were retrospectively examined. The patients were assigned to Group 1: incomplete definitive treatment; Group 2: complete definitive treatment; or Group 3: complete definitive treatment with additional salvage surgery. The data of 273 patients (90, 166, and 17 in Groups 1, 2, and 3, respectively) were analyzed. In the survival analysis, the median overall survival of Groups 1, 2, and 3 were 2.6, 10.3, and 29.5 months, respectively. A significant difference in 3-year overall survival was observed among the groups (2.2%, 12.4%, and 48.5%, p < 0.001). In multivariable analysis, the independent risk factors for incomplete definitive treatment included poor performance score (hazard ratio (HR): 5.23, p = 0.001), bone metastasis (HR: 2.18, p = 0.024), airway invasion (HR: 2.90, p = 0.001), and liver cirrhosis (HR: 3.20, p = 0.026). Incomplete definitive treatment is associated with a far worse prognosis. Poor performance, bone metastasis, airway invasion, and liver cirrhosis are risk factors for incomplete treatment.