Prognostic value of metastatic lymph nodal ratio in squamous cell carcinoma of esophagus: A three-step extrapolative study

BACKGROUND: Transthoracic esophagectomy (TTE) and transhiatal esophagectomy (THE) are the two most common surgical approaches for carcinoma esophagus. Several studies have shown lymph nodal involvement to be one of the most important prognostic factors in carcinoma esophagus. AIMS: The primary objective of this study was to explore the effectiveness of the ratio of positive lymph nodes to excised lymph nodes, namely the metastatic lymph nodal ratio (MLNR) as a prognostic factor in the survival of patients with carcinoma esophagus. SETTINGS AND DESIGN: Retrospective analysis of a prospective database. MATERIALS AND METHODS: A review of the operated esophageal cancer patients treated at a tertiary cancer center in South India between January 2002 and December 2006. Statistical analysis was done with the help of SPSS version 17 software (SPSS Inc., Chicago, IL). Proportions were compared using the Chi-square test. Survival data was generated using life table methods. Differences in survival estimates were compared using log-rank test. RESULTS AND CONCLUSIONS: Our study emphatically showed that the survival outcomes of patients with squamous cell carcinoma of the esophagus can be discriminated based on the MLNR groups, and it can be a reliable prognostic indicator. The overall survival for patients undergoing TTE, or THE for the entire cohort of patients was however not statistically significant. Whether a more aggressive TTE is a better esophageal cancer operation or whether MLNR is the factor that can significantly impact survival regardless of the technique is an issue that would require further investigation.