To evaluate intermediate- and long-term oncological outcomes of active surveillance (AS) for localized renal masses (LRMs).
This systematic literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and registered on PROSPERO (CRD42021230416). Studies on AS for LRMs with at least 3 years' follow-up were eligible. Two review authors independently screened the literature, extracted data, and assessed risk of bias. The primary outcomes were metastasis rate, renal cell carcinoma (RCC)-specific mortality (RCC-SM) and all-cause mortality (ACM). Pooled estimates were obtained from random-effects models. Subgroup analyses were performed for small renal masses (SRMs; ≤4 cm) and non-SRMs (>4 cm).
We analysed 18 unique cohorts comprising 2066 patients. The pooled initial maximum tumour size was 2.8 cm (95% confidence interval [CI] 2.7-3.0) and the percutaneous biopsy rate was 28%. The pooled mean annual growth rate was 2.8 mm (95% CI 2.1-3.4). Within a pooled mean follow-up of 53 months, 2.1% (95% CI 1.0-3.6) of patients developed metastatic disease, 1.0% (95% CI 0.3-2.1) died from RCC and 22.6% (95% CI 15.8-30.2) died from any cause. For patients with SRMs (nine studies, n = 987), the pooled metastasis rate was 1.8% (95% CI 0.5-3.7), RCC-SM was 0.6% (95% CI 0-2.1), and ACM was 28.5% (95% CI 17.4-41.4). Across five studies reporting on outcomes of 239 patients with non-SRMs, the pooled metastasis rate was 5.1% (95% CI 0-17.3), RCC-SM was 2.1% (95% CI 0-8.9) and ACM was 29.1% (95% CI 13.6-47.3). This review is limited by non-standardized inclusion criteria, definitions and follow-up, data heterogeneity, limited patient numbers in sub-analyses and absence of high-quality studies.
Active surveillance is a safe intermediate- and long-term management option for well-selected patients with LRMs, especially those with SRMs. Limited data are available for non-SRMs, but current evidence would support further evaluation of this approach in selected patients. It is not possible to draw definitive conclusions until more high-quality data become available.
BJU international. 2021 May 31 [Epub ahead of print]
Tobias Klatte, Alessandro Berni, Sergio Serni, Riccardo Campi
Department of Urology, Royal Bournemouth Hospital, Dorset University Hospitals NHS Foundation Trust, Bournemouth, UK., Unit of Urological Robotic Surgery and Renal Transplantation, Careggi Hospital, University of Florence, Florence, Italy.