A computed tomography-based study of the non-surgical N staging system for esophageal carcinoma / 中华放射肿瘤学杂志

ABSTRACT

Objective To improve the non?surgical N staging system for esophageal carcinoma ( EC) . Methods A retrospective analysis was performed in 501 patients newly diagnosed with esophageal squamous cell carcinoma who received radiotherapy in our hospital from 2009 to 2013. The impacts of the supraclavicular lymph nodes and mediastinal lymph nodes on the overall survival ( OS) rate were analyzed. The original non?surgical N staging system was improved and the proposed N staging system was evaluated. The OS rates were calculated using the Kaplan?Meier method and analyzed using the log?rank test. The univariate and multivariate analyses were performed using the log?rank test and Cox regression model, respectively. Results The 3?and 5?year sample sizes were 404 and 205, respectively. In all patients, the 1?, 3?, and 5?year OS rates were 64?9%, 26?5%, and 18?3%, respectively;the 1?, 3?, and 5?year distant metastasis?free ( DMF) rates were 86?2%, 68?9%, and 67?3%, respectively;the 1?, 3?, and 5?year local control rates were 72?7%, 53?1%, and 43?6%, respectively. The univariate analysis showed that the incidence, 3?year OS rate, and 3?year DMF rate of supraclavicular lymph node metastases in patients with cervical and upper?thoracic EC were significantly higher than those in patients with middle?thoracic and lower?thoracic EC ( 25?7% vs. 14?2%, P=0?034;24?2% vs. 11?5%, P=0?016;84?8% vs. 69?2%, P=0?007) . The multivariate analysis also showed that the number of metastatic lymph nodes was an independent prognostic factor for the OS and DMF rates in patients ( P= 0?000;P= 0?007 ) . Conclusions It is reasonable to classify upper?thoracic EC with supraclavicular lymph node metastasis into stage N1 diseases. The proposed N staging system with the factor of the number of metastatic lymph nodes is more scientific and objective than the original N staging system.