Active surveillance of renal masses, which includes serial imaging with the possibility of delayed treatment, has emerged as a viable alternative to immediate therapeutic intervention in selected patients. Active surveillance is supported by evidence that many benign masses are resected unnecessarily, and treatment of small cancers has not substantially reduced cancer-specific mortality. These data are a call to radiologists to improve the diagnosis of benign renal masses and differentiate cancers that are biologically aggressive (prompting treatment) from those that are indolent (allowing treatment deferral). Current evidence suggests that active surveillance results in comparable cancer-specific survival with a low risk of developing metastasis. Radiology is central in this. Imaging is used at the outset to estimate the probability of malignancy and degree of aggressiveness in malignant masses and to follow up masses for growth and morphologic change. Percutaneous biopsy is used to provide a more definitive histologic diagnosis and to guide treatment decisions, including whether active surveillance is appropriate. Emerging applications that may improve imaging assessment of renal masses include standardized assessment of cystic and solid masses and radiomic analysis. This article reviews the current and future role of radiology in the care of patients with renal masses undergoing active surveillance.

© RSNA, 2021

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肾脏肿块的主动监测，包括可能延迟治疗的连续成像，已成为对选定患者立即治疗干预的可行替代方案。许多良性肿块被不必要地切除的证据支持主动监测，并且小癌症的治疗并没有显着降低癌症特异性死亡率。这些数据呼吁放射科医生改进对良性肾脏肿块的诊断，并将具有生物侵袭性（促进治疗）的癌症与惰性（允许延迟治疗）区分开来。目前的证据表明，主动监测可产生相当的癌症特异性存活率，并且发生转移的风险较低。放射学是其中的核心。成像最初用于估计恶性肿块的恶性概率和侵袭性程度，并跟踪肿块的生长和形态变化。经皮活检用于提供更明确的组织学诊断并指导治疗决策，包括主动监测是否合适。可以改善肾脏肿块成像评估的新兴应用包括囊性和实性肿块的标准化评估以及放射组学分析。本文回顾了放射学在接受主动监测的肾肿块患者护理中的当前和未来作用。包括主动监测是否合适。可以改善肾脏肿块成像评估的新兴应用包括囊性和实性肿块的标准化评估以及放射组学分析。本文回顾了放射学在接受主动监测的肾肿块患者护理中的当前和未来作用。包括主动监测是否合适。可以改善肾脏肿块成像评估的新兴应用包括囊性和实性肿块的标准化评估以及放射组学分析。本文回顾了放射学在接受主动监测的肾肿块患者护理中的当前和未来作用。

© 北美放射学会，2021

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