Essential risk factors for operative mortality in elderly esophageal cancer patients registered in the National Clinical Database of Japan

Background: With the aging of society and increasingly longer of life expectancy, elderly patients with esophageal cancer are more commonly encountered. This study aimed to identify the risk factors for operative mortality after esophagectomy in elderly patients. Methods: We used data from the National Clinical Database of Japan. After cleaning the data, 10,633 records obtained from 861 hospitals were analyzed. A risk model for operative mortality was developed using risk factors from the entire study population. Then, odds ratios (OR) were compared between age categories using this risk model. Results: In this study, 1959 (18.4%) patients were ≥ 75 years (defined as “elderly” in this study). Eighteen variables, including T4b, N2–N3, and M1 in the TNM classification, were included in the risk model for operative mortality. The ORs increased in age categories < 65, 65–74, and ≥ 75 years for N2–N3 (1.172, 1.200, and 1.588, respectively), and M1 (2.189, 3.164, and 4.430, respectively). Based on these results, we also focused on residual tumors, which are caused by extensive tumor development. The operative mortality in the elderly group with residual tumors increased to more than twice than that in the non-elderly groups (15.9 vs. 5.5 or 6.5%) and was much higher than that in elderly patients without residual tumors (15.9 vs. 4.6%). Conclusion: We should carefully select the treatment for elderly patients with highly advanced tumors, which result in N2–N3 and M1, to avoid unfavorable short-term outcomes. In addition, R0 resection is important in preventing operative mortality among elderly patients.