Objective: This study was undertaken to investigate the clinicopathological factors that influence the growth of a small renal mass (SRM) in patients subjected to a delayed surgery intervention.
Methods: We reviewed the clinical records of 37 patients with SRM 4 cm at diagnosis, who underwent delayed surgical intervention during surveillance from January 2000 to December 2013. Radiographic evaluation using computed tomography (CT) scan, magnetic resonance imaging (MRI) were performed at least every 6 months and the tumor size was determined at least twice.
Results: Histopathological analysis revealed that in 35 of the 37 patients the tumor was malignant in stage pT1aN0M0. There were 28 clear cell carcinomas and 7 non clear cell carcinomas. There was a significant difference in the time to tumor doubling (TTD) among clear cell carcinomas (p=0.033). There was also a significant difference in the tumor growth rate (mm/year) of clear cell carcinomas between male and female patients (p=0.028).
Conclusion: The growth rate of small renal mass was slow in the majority of our patients. Pathological grade and gender significantly influenced the growth of clear cell carcinomas.