Prognostic analysis of esophageal cancer in elderly patients: metastatic lymph node ratio versus 2010 AJCC classification by lymph nodes

BACKGROUND Recent studies have proposed a new prognostic factor (metastatic lymph node ratio, or MLNR) for patients with esophageal cancer (EC). However, to the best of our knowledge, there have been no studies conducted to date regarding MLNR in elderly patients. The aim of this study was to determine the prognostic value of MLNR staging compared with the 2010 American Joint Committee on Cancer (AJCC) N staging in elderly patients with EC. METHODS From January 2001 to December 2009, a retrospective analysis of 132 consecutive patients older than 70 years of age with esophageal squamous cell carcinoma (ESCC) was conducted. Prognostic factors for disease-specific survival were analyzed. Receiver operating characteristic curves were also plotted to verify the accuracy of MLNR staging and N staging for survival prediction. RESULTS The disease-specific survival rates of N0, N1, N2 and N3 patients according to the AJCC Cancer Staging Manual Seventh Edition N staging were 65.5%, 42.9%, 22.2% and 0, respectively (N0 vs N1, P = 0.017; N1 vsN2, = 0.050; N2 vs N3, P < 0.001). The disease-specific survival rates of MLNR0, MLNR1, MLNR2 and MLNR3 patients were 65.5%, 45.0%, 21.1% and 0, respectively (MLNR0 vsMLNR1, P = 0.026; MLNR1 vs MLNR2, P = 0.033; MLNR2 vs MLNR3, P = 0.015). The areas under the curve were 0.731 for the 2010 AJCC N staging and 0.737 for the MLNR staging. CONCLUSION MLNR is an independent predictor of survival in elderly patients with ESCC. MLNR staging predicts survival after EC similarly to the 2010 AJCC N classifications and should be considered an alternative to current N staging.