Analysis of new N-category on prognosis of oesophageal cancer with positive lymph nodes in a Chinese population

Support Vector Machines Model of Computed Tomography for Assessing Lymph Node Metastasis in Esophageal Cancer with Neoadjuvant Chemotherapy

Objective

The aim of this study was to diagnose lymph node metastasis of esophageal cancer by support vector machines model based on computed tomography.

Materials and Methods

A total of 131 esophageal cancer patients with preoperative chemotherapy and radical surgery were included. Various indicators (tumor thickness, tumor length, tumor CT value, total number of lymph nodes, and long axis and short axis sizes of largest lymph node) on CT images before and after neoadjuvant chemotherapy were recorded. A support vector machines model based on these CT indicators was built to predict lymph node metastasis.

Results

Support vector machines model diagnosed lymph node metastasis better than preoperative short axis size of largest lymph node on CT. The area under the receiver operating characteristic curves were 0.887 and 0.705, respectively.

Conclusions

The support vector machine model of CT images can help diagnose lymph node metastasis in esophageal cancer with preoperative chemotherapy.

Evaluation of the 7(th) edition of the UICC-AJCC tumor, node, metastasis classification for esophageal cancer in a Chinese cohort

BACKGROUND

To assess and evaluate the prognostic value of the 7(th) 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 6(th) 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 6(th) and 7(th) 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 6(th) edition and the 7(th) edition (P<0.001). According to the 7(th) 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 7(th) edition staging system. Based on the 7(th) 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 6(th) and 7(th) edition staging system.

CONCLUSIONS

The 7(th) 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.