The impact of gender and size on the pathology of small renal mass

Without surgery, it is hard to predict the histology of small (≦ 4 cm) renal masses (SRMs) based on images. This study attempted to investigate whether clinical parameters were correlated with the pathological presence of SRM carcinomas. We conducted a retrospective chart review of 60 patients with 61 suspicious SRMs on radiological examination who received radical nephrectomy (RN) or partial nephrectomy (PN) between January 2003 and February 2011 in the China Medical University Hospital (CMUH). The correlations between patient age, gender, tumor size, and pathological features were calculated and analyzed. Of the 61 SRMs, there were 51 (83.6%) renal cell carcinoma (RCC), seven (11.5%) angiomyolipoma, two (3.3%) oncocytoma, and one (1.6%) metanephric adenoma. Regarding the histological variants of these cases of RCC, 44 were categorized as the clear cell type, two as the papillary type, and five as the chromophobe type. The incidence of benign tumor was greater in females (p = 0.014) and tumor size 2 cm or less (p = 0.02), compared with males and tumor size more than 2 cm, respectively. Surgical intervention is generally recommended for medically fit patients.