Clinical study on postoperative recurrence in patients with pN1 esophageal squamous cell carcinoma

BACKGROUND The 7th edition Union for International Cancer Control esophageal cancer staging system has changed the pathological N stage from N0, N1 (the existence state of regional lymph node metastasis) to N0, N1, N2, and N3 (number of regional lymph node metastasis). This study was designed to analyze the influencing factors of early recurrence in patients with pathological N1 stage (pN1 stage) esophageal squamous cell carcinoma (ESCC) after radical esophagectomy. METHOD A retrospective study of 95 consecutive pN1 stage ESCC patients was conducted. The Cox proportional hazards model was used to determine the independent risk factors for recurrence. RESULTS Recurrence was recognized in 52 patients (54.7%) within three years after surgery. The median time to tumor recurrence was 14.2 months. Locoregional recurrence was found in 42 patients (44.2%) and hematogenous metastasis in 10 patients (10.5%). Recurrence closely correlated with pT stage, positive lymph node metastasis (LNM) in 2-station and/or 2-field, pathologic stage, intramural metastasis, lymph-vascular invasion, and postoperative adjuvant chemotherapy (χ(2) = 8.853∼65.695, P < 0.05). Cox multivariate analysis showed that pT3-4a stage (odds ratio [OR] = 3.604, P = 0.027), positive LNM in 2-station (OR = 4.834, P = 0.009) or 2-field (OR = 5.689, P = 0.003) and no adjuvant chemotherapy (OR = 1.594, p = 0.048) were independent risk factors for postoperative recurrence. CONCLUSION Adjuvant chemotherapy might be helpful to reduce the recurrence rate of pN1 patients with thoracic ESCC. Induction therapy could further improve the therapeutic effect of pN1 ESCC with suspected multi-station and/or multi-field LNM.