Renal oncocytoma growth rates before intervention

Area of Science:

• Nephrology
• Urologic Oncology
• Radiology

Background:

• Renal oncocytomas are benign kidney tumors.
• Distinguishing between benign and malignant renal masses can be challenging.
• Understanding the growth patterns of renal oncocytomas is crucial for management decisions.

Purpose of the Study:

• To quantify the growth rates of renal oncocytomas prior to treatment.
• To compare the growth of renal oncocytomas with known growth rates of renal cell carcinoma.

Main Methods:

• Retrospective analysis of 33 pathologically confirmed renal oncocytomas.
• Serial contrast-enhanced computed tomography (CT) scans over at least one year.
• Tumor measurements by two radiologists to calculate growth rates and interobserver variability.

Main Results:

• Oncocytomas grew from a mean initial size of 17 mm to 26 mm at treatment.
• The mean growth rate was 2.9 mm/year (median 2.7 mm/year).
• Interobserver variability was minimal, with an intraclass correlation coefficient of 0.99.

Conclusions:

• Renal oncocytomas exhibit growth rates similar to renal cell carcinoma.
• Tumor growth alone cannot differentiate benign from malignant renal masses.
• Active surveillance of small renal masses requires careful evaluation before proceeding to intervention.