Prognostic nomogram for disease-free survival in patients with renal adenocarcinoma

Abstract

Objective: The aim of this study was to develop a postoperative prognostic nomogram for disease-free survival in patients with renal adenocarcinoma.

Materials and methods: A total of 224 patients with organ-confined or locally advanced renal adenocarcinoma were treated with radical or partial nephrectomy. The variables included in the model were age, histological type, pathological stage, Fuhrman grade and DNA ploidy. Tumor recurrence was defined as any clinical evidence of recurrence. The probability of progression-free survival was calculated using the Kaplan-Meier estimate, and multivariate analysis was performed using a Cox regression. The nomogram was created using the data obtained from the Cox regression.

Results: Tumor recurrence was detected in 89 patients (39.74%). The median progression-free time in these patients was 9.55 months (range 0-133). Of these patients, 70.9% relapsed during the first 2 years, and only 15 patients (6.9%) were alive but ill at the end of the study. The probability of progression-free survival at 5 and 10 years was 66.64 and 61.97%, respectively. We performed a statistical validation of the model with accurate predictions that were discriminated with a confidence interval of 0.75 (comparing the predicted and actual probability). According to the nomogram obtained, patients with low-grade, diploid, organ-confined tumors would be candidates for follow-up not exceeding 5 years due to the low probability of recurrence (<40 points).

Conclusion: The nomogram we developed is clinically relevant and can provide prognostic information for both patients and researchers. In addition, it can be used by researchers during the monitoring protocols that categorize patients based on their relative risk of disease progression.