为了评估从临床分期局限型到局部晚期pT3a的病理分期对肾细胞癌（RCC）患者的生存影响，以及该情况下各种手术方法的肿瘤学安全性，并开发一种基于机器学习的现代临床相关模型，用于个体术前预测pT3a分期上升。回顾性分析了2000年至2019年在法国多机构肾癌数据库UroCCR中接受部分肾切除（PN）或根治性肾切除（RN）治疗的cT1/cT2a RCC患者的临床数据。在训练/测试分裂后，将七种机器学习算法应用于该队列以开发pT3a上分期的预测模型。经过G计算，比较PN和RN对于pT3a肿瘤的无疾病生存（DFS）和总生存（OS）率的生存曲线。共纳入了4395名患者，其中667名患者（15％，337名PN和330名RN）患有pT3a上分期的RCC。UroCCR-15预测模型的接受者操作特征曲线下面积为0.77。经过混杂因素调整的生存分析显示，对于pT3a肿瘤，PN与RN的DFS或OS没有差异（DFS：风险比[HR] 1.08，P=0.7；OS：HR 1.03，P>0.9）。我们的研究表明，机器学习技术在评估和预后上分期的RCC中可以发挥有用的作用。在偶然上升的情况下，即使对于大肿瘤大小，PN也不会影响肿瘤学结果。©2023 The Authors.由John Wiley＆Sons Ltd代表BJU International出版的BJU International。

To assess the impact of pathological upstaging from clinically localized to locally advanced pT3a on survival in patients with renal cell carcinoma (RCC), as well as the oncological safety of various surgical approaches in this setting, and to develop a machine-learning-based, contemporary, clinically relevant model for individual preoperative prediction of pT3a upstaging.Clinical data from patients treated with either partial nephrectomy (PN) or radical nephrectomy (RN) for cT1/cT2a RCC from 2000 to 2019, included in the French multi-institutional kidney cancer database UroCCR, were retrospectively analysed. Seven machine-learning algorithms were applied to the cohort after a training/testing split to develop a predictive model for upstaging to pT3a. Survival curves for disease-free survival (DFS) and overall survival (OS) rates were compared between PN and RN after G-computation for pT3a tumours.A total of 4395 patients were included, among whom 667 patients (15%, 337 PN and 330 RN) had a pT3a-upstaged RCC. The UroCCR-15 predictive model presented an area under the receiver-operating characteristic curve of 0.77. Survival analysis after adjustment for confounders showed no difference in DFS or OS for PN vs RN in pT3a tumours (DFS: hazard ratio [HR] 1.08, P = 0.7; OS: HR 1.03, P > 0.9).Our study shows that machine-learning technology can play a useful role in the evaluation and prognosis of upstaged RCC. In the context of incidental upstaging, PN does not compromise oncological outcomes, even for large tumour sizes.© 2023 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.