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Impact of Age on Long-Term Survival in Patients with Esophageal Cancer Who Underwent Transthoracic Esophagectomy

Background and Objective: Esophagectomy, which is one of the most invasive operations among gastrointestinal surgeries, deteriorates the physical condition of patients. Such deterioration may be severe in elderly patients and advanced age may negatively affect long-term survival. However, elderly patients are more likely to die from cancer-unrelated causes than younger patients. Therefore, when comparing the survival of elderly patients after cancer surgery with that of younger patients, it is necessary to control the influence of cancer-unrelated death. To address this problem, we calculated the relative survival and applied the excess hazard model to control the influence of competing risk of death from cancer. Methods: We retrospectively analyzed 505 patients with thoracic esophageal cancer who underwent transthoracic esophagectomy. Prognostic information was followed up to 10 years after surgery or until death in all patients. Prognostic information of patients lost to follow-up was retrieved from the Osaka Cancer Registry’s database. First, we identified prognostic variables as confounders of age by univariate and multivariate analysis. Then, we estimated age effects using the excess hazard model including the prognostic variables as confounders. Results: Univariate and multivariate analysis showed that clinical stage, residual tumor, and postoperative complications (p < 0.1) were confounders of age. Multivariate excess hazard model revealed that age was not a significant prognostic factor at any cutoff point. However, the excess hazard ratio of death tended to increase continuously in patients aged 70 years or older. Conclusions: When clinicians offer esophagectomy for esophageal cancer, age per se should not be a limiting factor. Strict evaluation of patients should be performed before surgery, especially in the elderly.