Overall Survival for Esophageal Squamous Cell Carcinoma with Multiple Primary Cancers after Curative Esophagectomy—A Retrospective Single-Institution Study

SIMPLE SUMMARY: With a strong association between esophageal cancer and multiple primary cancers (MPCs), physicians encounter difficult decision making for appropriate treatment. By analyzing long-term survival for esophageal squamous cell carcinoma (SCC) associated with MPCs, patients with antecedent/synchronous cancers showed similar survival benefit in comparison with esophageal SCC only. The most common site of other primary cancers is the head and neck, which also showed no inferiority in overall survival (OS) among sites of MPCs. Once curative esophagectomy can be achieved, surgery should be selected as a potential therapeutic approach if indicated. ABSTRACT: Background: Advances in surgical techniques and treatment modalities have improved the outcomes of esophageal cancer, yet difficult decision making for physicians while encountering multiple primary cancers (MPCs) continues to exist. The aim of this study was to evaluate long-term survival for esophageal squamous cell carcinoma (SCC) associated with MPCs. Methods: Data from 544 patients with esophageal SCC who underwent surgery between 2005 and 2017 were reviewed to identify the presence of simultaneous or metachronous primary cancers. The prognostic factors for overall survival (OS) were analyzed. Results: Three hundred and ninety-seven patients after curative esophagectomy were included, with a median observation time of 44.2 months (range 2.6–178.6 months). Out of 52 patients (13.1%) with antecedent/synchronous cancers and 296 patients without MPCs (control group), 49 patients (12.3%) developed subsequent cancers after surgery. The most common site of other primary cancers was the head and neck (69/101; 68.3%), which showed no inferiority in OS. Sex and advanced clinical stage (III/IV) were independent risk factors (p = 0.031 and p < 0.001, respectively). Conclusion: Once curative esophagectomy can be achieved, surgery should be selected as a potential therapeutic approach if indicated, even with antecedent/synchronous MPCs. Subsequent primary cancers were often observed in esophageal SCC, and optimal surveillance planning was recommended.