Predictive factors for benign lesions in partially or radically resected kidneys in a single independent cancer center

Objective: To assess the incidence and predictive factors of benign renal lesions in surgical specimens obtained at our institution.

Methods: We carried out a retrospective assessment of 96 renal nodules, diagnosed by dynamic multi-detector row helical computed tomography, and resected by either radical or partial nephrectomy between January 2004 and November 2011. The incidence of benign lesions in 1-cm increments of diameter was determined and the predictive factors for these lesions were then evaluated.

Results: Of the 96 nodules, histology confirmed that 13 (13.5%) were benign. The incidence of benign lesions was 25.0% for nodules <1 cm, 23.8% for nodules 1-1.9 cm, 11.5% for nodules 2-2.9 cm, 7.7% for nodules 3-3.9 cm, and 7.1% for nodules ≥4 cm. Multivariate analysis showed that younger age (<60 years; odds ratio [OR] = 5.23), female gender (OR = 4.78), and smaller nodule size (<3 cm; OR = 6.14) were significant predictive factors for benign lesions.

Conclusions: The incidence of benign lesions in this study (13.5% of total cases) was relatively low compared with recent studies from Western countries that reported an incidence of 15-20%. Significant predictive factors for benign lesions included younger age, female gender, and smaller tumor size.