Nomogram for predicting the prognosis of metastatic thymic epithelial tumors.

BACKGROUND

The majority of patients diagnosed with thymic epithelial tumors (TETs) are often at an advanced stage that precludes cure. This study aimed to develop a nomogram to predict the prognosis of metastatic TETs.

METHODS

Patients diagnosed as metastatic TETs in Sun Yat-sen University Cancer Center from July 2000 to November 2021 were retrospectively reviewed. A nomogram was developed to predict the prognosis of metastatic TETs. The performance of the nomogram was assessed by the concordance index (C-index), calibration curves, and decision curve analysis curves. Based on the nomogram scores, patients were divided into different prognostic groups.

RESULTS

A total of 254 patients were enrolled. The median overall survival (OS) was 53.03 months [95% confidence interval (CI): 40.56-65.51]. Univariate and multivariate analyses showed that World Health Organization (WHO) histologic classification type C, Masaoka-Koga stage IVb, Karnofsky performance status (KPS) score 70-80, and baseline serum albumin level <40 g/L were independent poor prognostic factors of OS. These factors were then taken into the development of nomogram model. The C-index was 0.68 (95% CI: 0.59-0.79), indicating good performance. The risk groups were categorized by nomogram scores with a threshold at 112 score. The median OS in the high-risk group was much shorter than that of the low-risk group [28.60 versus 74.17 months, hazard ratio (HR): 2.44; 95% CI: 1.65-3.62; P<0.001].

CONCLUSIONS

WHO histologic classification, Masaoka-Koga stage, KPS score, and baseline serum albumin level were identified as independent prognostic factors of OS in metastatic TETs. This study developed a nomogram model effectively predicting the prognosis of metastatic TETs.