Establishment and validation of prognostic nomograms to predict the overall and cancer-specific survival in patients with hepatic malignant vascular tumors.

Objective: To characterize the clinicopathologic features and to investigate the prognostic nomograms for overall survival (OS) and cancer-specific survival (CSS) in patients with Hepatic malignant vascular tumors (HMVT).

Method: Patients diagnosed with HMVT between 1973 and 2015 were screened from the Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier (KM) was used for survival analysis. The univariate and multivariate Cox analyses were performed to identify independent predictors. Furthermore, the prognostic nomograms were established and evaluated.

Results: A total of 510 HMVT patients were collected, and randomly divided into HMVT-training (N=308) and validation cohort (N=202) groups. The 3- and 5-year OS for overall HMVT were 21.3% and 19.8%, and the corresponding CSS was 29.8% and 27.7% respectively. Age at diagnosis, grade, tumor size, and histological type were identified as prognostic factors for OS and CSS in patients with HMVT. However, sex was just for predicting CSS, and T stage was only an indicator of OS. These factors were further utilized to construct the nomograms for OS and CSS in the HMVT-training cohort showing credible performance with the C-index of 0.763 and 0.762, respectively. Moreover, the AUC value for 1-, 3-, 5-year OS was 0.873, 0.905 and 0.898, and the corresponding value for CSS was 0.808, 0.794 and 0.788 respectively. Additionally, the calibration curves demonstrated a favorable agreement between the predicted and actual 1-, 3- and 5-year survival rates both in the training and validated cohorts.

Conclusion: This was the largest population-based study to describe the clinicopathologic characteristics in patients with HMVT. Moreover, we established and validated prognostic nomograms that indicated an accurate prediction for 1-, 3- and 5-year of OS and CSS.