Clinical characteristics and prediction model of long time survival of patients with stage M1 Siewert type II esophagogastric junction adenocarcinoma.

Background: We aimed to study the clinical manifestations of the patients with stage M1 Siewert type II esophagogastric junction adenocarcinoma and more than 1-year overall survival and establish a prognosis prediction model.

Methods: From the SEER database, 638 patients were chosen between 2011 and 2017. Patients were separated into two groups, including the long-time survival group (≥1 year), and the shorter time survival group (<1 year). The analysis of differences in clinical characteristics (age, race, sex, stage T, stage N, grade, surgery, distant metastasis, survival status and time) between the different groups was performed by using the chi-square test. The predictors of overall survival was selected by using the Cox regression. The calibration curves and C-index were used to verify the nomogram.

Results: The chi-square test showed that the proportion of patients with the age of ≥65 years in the long time survival group was lower than the short time survival group (P=0.008). The proportion of patients who received surgery was higher in the long time survival group (13.5% 5.3%, P<0.001). There was a significantly lower proportions of bone metastasis in the long time survival group (P=0.036). Multivariate analyses indicated factors such as age, surgery, bone, liver, and lung metastasis were associated with prognosis. The C-index of the nomogram was 0.860.

Conclusions: Age, surgery, bone, liver, and lung metastasis were related to the overall survival of a patient with stage M1 Siewert type II esophagogastric junction adenocarcinoma. We constructed a nomogram to help predict 1-year overall survival for a patient with stage M1 Siewert type II esophagogastric junction adenocarcinoma.