Impact of Tumor Size on Survival Outcome in Esophageal Squamous Cell Carcinoma After Esophagectomy Following Neoadjuvant Chemotherapy

Background. Large tumor size is a prognostic factor in esophageal squamous cell carcinoma (ESCC). However, the effect of tumor size on outcomes following neoadjuvant chemotherapy (NAC) has not been evaluated. This study aimed to assess the influence of tumor size on prognosis of patients undergoing esophagectomy after NAC. Patients and Methods. This study was made up of 272 patients who underwent esophagectomy after NAC at Kobe University Hospital. We evaluated the pathological tumor size and determined the cutoff level for tumor size using receiver operating characteristics analysis to the survival status. Cox proportional hazards regression analyses were performed to identify prognostic factors. Results. The patients were categorized into two groups: patients with tumor sizes >= 36 mm and < 36 mm. Deep pathological tumor invasion and worse histological response to NAC were associated with tumor size >= 36 mm. In patients with pT0-1, pT2, and pT4 ESCC, no significant differences in overall survival (OS) rates were observed between the two groups. In patients with pT3, OS of the tumor size >= 36 mm group was significantly worse than that of the tumor size < 36 mm group (p < 0.0001). Multivariate analysis in pT3 patients revealed tumor size >= 36 mm was an independent risk factor for OS. The 5-year OS rate was 10% in patients with tumor size >= 36 mm pT3 ESCC with pathological lymph node metastasis (p < 0.0001). Conclusions. Tumor size >= 36 mm is an independent risk factor for poorer survival in pT3 patients. Furthermore, tumor size >= 36 mm with pathological lymph node metastasis in pT3 patients was associated with very poor survival.