患有小肾癌（SRM）的患者在积极监测（AS）期间经受良好的无转移生存（MFS）和癌症特异性生存（CSS），但有观察到总体生存（OS）的差异，这可能是由于选择了年龄较大/有共病的患者进行AS。很少有研究评估临床平衡组中的AS与原发治疗，我们从机构数据库（2000-2020）中识别了年龄在55-75岁且肾肿瘤小于4cm（T1a）的患者。 我们对AS和肾切除术亚组的患者进行了精确匹配，包括年龄、性别、ECOG表现状态、活检状况和组织学。主要结果为OS和事件无进展生存（EFS）组合，其中包括OS、CSS、MFS、进展或系统疗法，我们在Cox比例风险模型中进行了测试。 我们识别了377名患者（205名AS，172名肾切除术）。在匹配后，队列是平衡的（n = 110;平均年龄为64岁，77%为男性，75%的ECOG分数为0）。在每个组中，47%进行了活检（以明显细胞组织学为主）。肾切除组预测的5年OS为96%，AS组为95%（肾切除术对AS的HR为0.83，95%置信区间（CI）为0.13-5.32；P = 0.8），相应的5年EFS率为93%和96%（HR 1.88，95% CI 0.35-10.15；P = 0.5）。在年龄和整体健康状况匹配良好的SRM病例中，我们观察到AS的5年OS率和EFS率比以前报道的要高；这些率与肾切除术后的结果没有显着差异。我们人群的匹配特征类似于当代队列的治疗组，结果支持AS在年轻、健康的患者中的安全性。 患者摘要：虽然已经表明针对小肾肿瘤的积极监测对于年龄较大和衰弱的患者是安全的，但其在年轻、健康的患者中的安全性尚未得到确认。我们比较了年龄在55-75岁的接受手术或积极监测的患者的结果，他们的年龄和整体健康状态相似。总体而言，5年后死亡的概率很低，两组之间没有显著差异，这表明积极监测在常规临床实践中是安全的。版权所有©2023年欧洲泌尿外科协会。由Elsevier B.V.出版。保留所有权利。

While patients with a small renal mass (SRM) on active surveillance (AS) experience excellent metastasis-free survival (MFS) and cancer-specific survival (CSS), differences in overall survival (OS) observed may be explained by selection of older/comorbid patients for AS. Few studies have evaluated AS versus primary intervention in clinically balanced groups. We identified patients aged 55-75 yr with an SRM (≤4 cm, T1a) in our institutional database (2000-2020). Patients from AS and nephrectomy subgroups were matched exactly for age, sex, Eastern Cooperative Oncology Group (ECOG) performance status, biopsy status, and histology. The primary outcomes were OS and an event-free survival (EFS) composite that included OS, CSS, MFS, progression, or systemic therapy, which we tested in Cox proportional-hazards models. We identified 377 patients (205 AS, 172 nephrectomy). The cohort was balanced after matching (n = 110; mean age 64 yr, 77% male, and 75% ECOG score 0). In each arm, 47% were biopsied (predominantly clear-cell histology). The predicted 5-yr OS was 96% for the nephrectomy group and 95% for the AS group (hazard ratio for nephrectomy vs AS [HR] 0.83, 95% confidence interval [CI] 0.13-5.32; p = 0.8), with corresponding 5-yr EFS rates of 93% and 96% (HR 1.88, 95% CI 0.35-10.15; p = 0.5). Among SRM cases well matched for age and overall health status, we observed higher 5-yr OS and EFS rates for AS than previously reported; the rates were not significantly different from those after nephrectomy. The matched characteristics of our population are similar to those for treatment arms in contemporary cohorts and the results support the safety of AS in younger, healthier patients. PATIENT SUMMARY: While it has been shown that active surveillance for small kidney tumors is safe in older and more frail patients, its safety in younger, healthier patients has not been confirmed. We compared outcomes for patients aged 55-75 yr who were managed with surgery or active surveillance, and were similar in age and overall health. The probability of death after 5 years was low overall and not significantly different between the groups, suggesting that active surveillance is safe in routine clinical practice.Copyright © 2023 European Association of Urology. Published by Elsevier B.V. All rights reserved.