Nomograms predict survival of patients with small bowel adenocarcinoma: a SEER-based study.

Abstract

Small bowel adenocarcinoma (SBA) is a rare malignant tumor with a poor prognosis. Most patients with SBA are diagnosed with advanced-stage disease. Due to the lack of randomized controlled trials and prospective studies, it is difficult to predict the prognosis of patients with SBA. Thus, this study aimed to establish a prognostic nomogram for evaluating the prognosis of SBA patients. The clinical features and follow-up data of all patients diagnosed with SBA during 2004-2016 were summarized from the Surveillance, Epidemiology, and End Results (SEER) database. We separated these patients into training and validation groups. Multivariate Cox regression analyses were performed to identify independent prognostic variables for predicting cancer-specific survival (CSS) and overall survival (OS). According to the independent risk factors, we established nomograms and used the calibration curves to evaluate the accuracy. The data of 3301 patients with SBA were collected from the SEER database. The multivariate analysis showed that age, marital status, tumor site, grade, TNM stage and surgical history were associated with CSS and OS (P < 0.05). Based on these results, we established nomograms of CSS and OS that can predict the 3- and 5-year survival rates of SBA patients (C-index > 0.7). The calibration curves showed that the predicted survival was very close to the actual survival. We analyzed the independent risk factors for prognosis of SBA patients, and established nomograms to predict the 3- and 5-year survival rates of OS and CSS. These new prognostic tools can help clinicians to predict the survival of patients with SBA, further to guide treatment strategy.