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Triggers for delayed intervention in patients with small renal masses undergoing active surveillance: a systematic
Riccardo Campi1,2,3, Francesco Sessa4,5, Francesco Corti4
1Department of Urology, Careggi Hospital, University of Florence, Florence, Italy - riccardo.campi@gmail.com.
Introduction:
Patients with small renal masses (SRM) can be exposed to overdiagnosis and overtreatment. As such, active surveillance (AS) is recommended by all Guidelines for selected patients. However, it remains underutilized. One key reason is the lack of consensus on the factors prompting delayed intervention (DI). Herein we provide an updated overview of the triggers for DI in patients with SRMs initially undergoing AS.
Evidence Acquisition:
A systematic review of the English-language literature was performed according to the PRISMA statement recommendations using the MEDLINE, Cochrane Central Register of Controlled Trials and Web of Science databases.
Evidence Synthesis:
Overall, 10 prospective studies including 1870 patients were included. Median patient age ranged between 64 and 75 years, while median tumor size between 1.7 cm to 2.3 cm. The proportion of cystic SRMs ranged from 0% to 30%. Baseline renal tumor biopsy was performed in 7-45.2% of patients. Among these, malignant histology was found in 28.5%-83.3% of cases. Overall, the median growth rate of SRMs ranged between 0.10 and 0.27 cm/year. The proportion of patients undergoing DI ranged between 7% and 44%, after a median AS period of 12-27 months. The most commonly performed type of DI was surgery. Of resected SRMs, 0% to 30% were benign. The actual triggers for DI were either tumor-related (renal mass growth, stage progression, development of local complications/symptoms) or patient-related (patient preference, improved medical conditions, or qualification for other surgical procedures). At a median follow-up of 21.7 - 57-6 months, the proportion of patients experiencing metastatic disease, cancer-specific and other-cause mortality was 0-3.1%, 0-4% and 0-45.6%, respectively.
Conclusions:
The available evidence shows that both tumor-related and patient-related factors are ultimate triggers for DI in patients with SRMs undergoing AS. However, the level of evidence is still low and further research is needed to individualize AS strategies according to both tumor biology and patient-related characteristics and values.
Insights
Active surveillance for small renal masses (SRMs) is underutilized due to unclear triggers for delayed intervention (DI). Both tumor and patient factors prompt DI, but more research is needed to personalize active surveillance strategies for SRMs.
Area of Science:
- Nephrology
- Urology
- Oncology
Background:
- Small renal masses (SRMs) often face overdiagnosis and overtreatment.
- Active surveillance (AS) is recommended but underutilized for SRMs.
- Lack of consensus on delayed intervention (DI) triggers hinders AS adoption.
Purpose of the Study:
- To provide an updated overview of triggers for delayed intervention (DI) in patients with small renal masses (SRMs) undergoing active surveillance (AS).
Main Methods:
- Systematic review of English-language literature.
- Searched MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science.
- Adhered to PRISMA statement recommendations.
Main Results:
- Included 10 prospective studies with 1870 patients; median age 64-75 years, tumor size 1.7-2.3 cm.
- Delayed intervention (DI) occurred in 7-44% of patients after 12-27 months of AS, most commonly via surgery.
- Triggers for DI included tumor growth, stage progression, complications, or patient-related factors; 0-30% of resected SRMs were benign.
Conclusions:
- Both tumor-related and patient-related factors trigger delayed intervention (DI) in small renal masses (SRMs) under active surveillance (AS).
- Current evidence level is low.
- Further research is necessary to individualize AS strategies based on tumor biology and patient values.
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