Original Article
Evaluation of the 7th edition of the UICC-AJCC tumor, node, metastasis classification for esophageal cancer in a Chinese cohort
Abstract
Background: To assess and evaluate the prognostic value of the 7th edition of the Union for International Cancer Control–American Joint Committee on Cancer (UICC-AJCC) tumor, node, metastasis (TNM) staging system for Chinese patients with esophageal cancer in comparison with the 6th edition.
Methods: A retrospective review was performed on 766 consecutive esophageal cancer patients treated with esophagectomy between 2008 and 2012. Patients were staged according to the 6th and 7th editions for esophageal cancer respectively. Survival was calculated by the Kaplan-Meier method, and multivariate analysis was performed using Cox regression model.
Results: Overall 3-year survival rate was 59.5%. There were significant differences in 3-year survival rates among T stages both according to the 6th edition and the 7th edition (P<0.001). According to the 7th edition, the 3-year survival rates of N0 (75.4%), N1 (65.2%), N2 (39.7%) and N3 (27.3%) patients were significant differences (P<0.001). Kaplan-Meier curve revealed a good discriminatory ability from stage I to IV, except for stage IB, IIA and IIB in the 7th edition staging system. Based on the 7th edition, the degree of differentiation, tumor length and tumor location were not independent prognostic factors on multivariate analysis. The multivariate analyses suggested that pT-, pN-, pTNM-category were all the independent prognostic factors based on the 6th and 7th edition staging system.
Conclusions: The 7th edition of AJCC TNM staging system of esophageal cancer should discriminate pT2–3N0M0 (stage IB, IIA and IIB) better when considering the esophageal squamous cell cancer patients. Therefore, to improve and optimize the AJCC TNM classification for Chinese patients with esophageal cancer, more considerations about the value of tumor grade and tumor location in pT2–3N0M0 esophageal squamous cell cancer should be taken in the next new TNM staging system.
Methods: A retrospective review was performed on 766 consecutive esophageal cancer patients treated with esophagectomy between 2008 and 2012. Patients were staged according to the 6th and 7th editions for esophageal cancer respectively. Survival was calculated by the Kaplan-Meier method, and multivariate analysis was performed using Cox regression model.
Results: Overall 3-year survival rate was 59.5%. There were significant differences in 3-year survival rates among T stages both according to the 6th edition and the 7th edition (P<0.001). According to the 7th edition, the 3-year survival rates of N0 (75.4%), N1 (65.2%), N2 (39.7%) and N3 (27.3%) patients were significant differences (P<0.001). Kaplan-Meier curve revealed a good discriminatory ability from stage I to IV, except for stage IB, IIA and IIB in the 7th edition staging system. Based on the 7th edition, the degree of differentiation, tumor length and tumor location were not independent prognostic factors on multivariate analysis. The multivariate analyses suggested that pT-, pN-, pTNM-category were all the independent prognostic factors based on the 6th and 7th edition staging system.
Conclusions: The 7th edition of AJCC TNM staging system of esophageal cancer should discriminate pT2–3N0M0 (stage IB, IIA and IIB) better when considering the esophageal squamous cell cancer patients. Therefore, to improve and optimize the AJCC TNM classification for Chinese patients with esophageal cancer, more considerations about the value of tumor grade and tumor location in pT2–3N0M0 esophageal squamous cell cancer should be taken in the next new TNM staging system.
