Active Surveillance for Small Renal Masses: When Less is More

Area of Science:

• Urology
• Oncology
• Nephrology

Background:

• Increasing detection of small renal masses (SRMs) necessitates defined management strategies.
• Active surveillance (AS) is a viable initial option for patients with SRMs.

Purpose of the Study:

• To establish selection criteria for AS in SRMs.
• To outline appropriate imaging and surveillance frequencies.
• To define triggers for delayed intervention (DI) and assess oncologic outcomes.

Main Methods:

• Systematic review of English language articles from PubMed.
• Inclusion criteria focused on evidence level, sample size, study design, and relevance.
• Keywords included "surveillance," "renal mass," "renal cell carcinoma," and "kidney cancer."

Main Results:

• Selection for AS considers patient factors, tumor characteristics, and patient preferences.
• Cross-sectional imaging is preferred; initial surveillance imaging every 3-4 months can be spaced out if growth is slow.
• Delayed intervention is indicated for rapid growth (>0.5cm/yr), increased size (>3-4cm), malignant biopsy, symptoms, or patient preference.

Conclusions:

• Initial AS is safe for most patients with SRMs (≤4cm).
• Management requires balancing risks and benefits, integrating patient and tumor factors.
• Adherence to close follow-up ensures oncologic outcomes are not compromised by AS.