Introduction/Background Uterine papillary serous carcinoma (UPSC) has aggressively biological behavior and leads to poor prognosis. However, clinicopathologic risk factors to predict cancer-specific survival of patients with stage I-II UPSC were still unclear. This study was undertaken to develop a prediction model of survival in patients with early-stage UPSC.

Methodology Using SEER database, we identified 964 patients with FIGO stage I-II UPSC who underwent at least hysterectomy between 2004–2015. Using proportional subdistribution hazards regression to compare cancer-specific death (CSD) for all patients. Based on the results of univariate and multivariate analysis, the variables were selected to construct a predictive model; and the prediction results of the model were visualized by nomogram to predict the cancer-specific survival and the response to adjuvant therapy of stage I-II UPSC patients.

Results The median age of the cohort is 67 years old. 17.1% (n=165) of the patients died of UPSC, while 8.6% of the patients died from other causes. On multivariate analysis, age (HR=1.45, P=0.021), tumor size (HR=1.81, P=0.014) and number of regional nodes removed (HR=0.52, P=0.003) were significantly associated with cumulative incidence of CSD. In the age≥67 years cohort, FIGO stage I-II was a risk factor for CSD (HR=1.83, P=0.036), and ≥ 10 lymph nodes removed was a protective factor (HR=0.50, P=0.01). Both combination of adjuvant chemotherapy and radiotherapy and adjuvant chemotherapy alone decreased the CSD of patients with stage I-II UPSC older than 67 years (HR=0.47, P=0.022; HR=0.52, P=0.024, respectively). The prediction model had great risk stratification ability as high-risk group had higher cumulative incidence of CSD than low-risk group (P<0.001). In the high-risk group, patients with adjuvant chemoradiotherapy had improved CSD compared with patients who did not receive any adjuvant therapy (P=0.037).

Conclusion Our prediction model has a good performance in predicting cancer-specific survival of early-stage UPSC patients and contributes to guide clinical treatment decision.

Disclosure Nothing to disclose