Establishment of a prognostic nomogram for evaluating non-adjuvant therapy in patients with stage I to III esophageal cancer: a population-based study.

BACKGROUND

According to reports from China, esophageal cancer ranked sixth in terms of morbidity and accounted for 6.26% of all cancer cases in China. This study aimed to establish an effective prognostic nomogram for non-adjuvant therapy in patients with stage I to III esophageal cancer.

METHODS

We took up cases from 2010 to 2015 from the Surveillance, Epidemiology, and End Results (SEER) database and used R language software to perform Kaplan-Meier survival curve and multivariate Cox regression analysis. Furthermore, we established the nomogram for non-adjuvant therapy patients with stage I to III esophageal cancer to predict 3- and 5-year esophageal cancer-specific survival rate. The prognostic ability of the nomogram was assessed using the C-index, area under the receiver operating characteristic (ROC) curve, and calibration chart.

RESULTS

The esophageal cancer-specific survival rate of cancer in the lower third of the esophagus was significantly higher than that of cancers in the upper-third of the esophagus as per the Kaplan-Meier curve. Based on the multivariate Cox regression analysis, sub variables such as advanced age, stage II and III, squamous cell carcinoma, moderately differentiated (grade II), poorly differentiated (grade III), and undifferentiated (grade IV) cancer significantly increased risk of prognosis in all patients. With a total of 150 points in the nomogram, the 3- and 5-year esophageal cancer-specific survival rates were 50% and 40% respectively. The value of C-index of this model was 0.851 and the value of the area under receiver operating curve projected 1-, 3-, and 5-year esophageal cancer-specific survival rates of 0.884, 0.874, and 0.856, respectively.

CONCLUSIONS

The established nomogram had good prediction ability for non-adjuvant therapy patients with stage I to III esophageal cancer.