Presentation, Treatment, and Prognosis of Esophageal Carcinoma in a Nationwide Comparison of Sweden and the Netherlands.

OBJECTIVE This population-based study aimed to compare presentation, treatment allocation and survival of potentially curable esophageal cancer patients between Sweden and the Netherlands. SUMMARY OF BACKGROUND DATA Identification of inter-country differences in treatment allocation and survival may be used for targeted esophageal cancer care improvement. METHODS Nationwide datasets were acquired from a Swedish cohort study and the Netherlands Cancer Registry. Patients with potentially curable (cT1-T4a/Tx, cN0/+, cM0/x) esophageal adenocarcinoma or squamous cell carcinoma (SCC) diagnosed in 2011-2015 were included. Multivariable logistic regression provided odds ratios (OR) for treatment allocation, and multivariable Cox model provided hazard ratios (HR) for overall survival, all with 95% confidence intervals (CI), adjusted for age, sex, year, tumor sub-location and stage. RESULTS Among 1980 Swedish and 7829 Dutch esophageal cancer patients, Swedish patients were older (71 vs 69 years, P <0.001) and had higher cT-stage (cT3: 49% vs 46%, P <0.001). After adjustment for confounders, Swedish patients were less frequently allocated to curative treatment (adenocarcinoma: OR=0.31, 95%CI 0.26-0.36; SCC: OR=0.28, 95%CI 0.22-0.36). Overall survival was lower in Swedish patients (adenocarcinoma: HR=1.36, 95%CI 1.27-1.46; SCC: HR=1.38, 95%CI 1.24-1.53), also when allocated to curative treatment (adenocarcinoma: HR=1.12, 95%CI 1.01-1.24; SCC: HR=1.34, 95%CI 1.14-1.59). CONCLUSION Swedish patients with potentially curable esophageal cancer were less frequently allocated to curative treatment, and showed lower survival compared to Dutch patients. The less pronounced inter-country survival difference after curative treatment suggests that the overall survival difference could at least partly be due to relative undertreatment of Swedish patients. Shared curative treatment thresholds across Europe may help improve survival of esophageal cancer patients.