To investigate the influence of nodal status on response and clarify the optimal treatment for operable esophageal squamous cell carcinoma (OSCC).
We retrospectively analyzed 1490 OSCC patients who underwent transthoracic esophagectomy and lymphadenectomy between December 1996 and December 2009 at the Sun Yat-sen University Cancer Center. The surgical approach and the number of resected lymph nodes (LNs) were considered in the assessment of surgery. Patients were classified according to their nodal statuses (N0 vs N1 vs N2-3). Overall survival was defined as the time from the date of death or final follow-up. Survival analysis was performed using the Kaplan-Meier method and differences between curves were assessed by the log-rank test. Univariate and multivariate Cox regression analyses were used to identify factors associated with prognosis. Statistical significance was assumed at a P < 0.05.
With a median time from surgery to the last censoring date for the entire cohort of 72.2 mo, a total of 631 patients were still alive at the last follow-up and the median survival time was 35.5 mo. The surgical approach (left transthoracic vs Ivor-Lewis/tri-incisional) was verified as independent prognostic significance in patients with N0 or N1 status, but not in those with N2-3 status. Similar results were also observed with the number of resected LNs (≤ 14 vs ≥ 15). Compared with surgery alone, combined therapy achieved better outcomes in patients with N1 or N2-3 status, but not in those with N0 status. For those with N2-3 status, neither the surgical approach nor the number of resected LNs reached significance by univariate analysis, with unadjusted HRs of 0.826 (95%CI: 0.644-1.058) and 0.849 (95%CI: 0.668-1.078), respectively, and aggressiveness of surgery did not influence the outcome; the longest survival was observed in those patients who received the combined therapy.
Combined therapy has a positive role in OSCC with LN metastasis, and aggressive surgical resection does not improve survival in patients with N2-3 status.