Prognostic significance of visceral obesity in patients with advanced renal cell carcinoma undergoing nephrectomy.

OBJECTIVES: To determine the effect of visceral obesity on the prognosis of advanced renal cell carcinoma patients undergoing nephrectomy.
METHODS: We reviewed clinicopathological data of 2187 patients who underwent nephrectomy for renal cell carcinoma (localized [T1-2, N0, M0], n = 1738 [79.5%]; advanced [T3-4, any N and M], n = 449 [20.5%]) at Samsung Medical Center, Seoul, Korea. The visceral fat area and subcutaneous fat area were determined at the level of the umbilicus on computed tomograms obtained before surgery. Patients were categorized as either viscerally obese or non-obese according to visceral fat area and visceral fat area/subcutaneous fat area ratio.
RESULTS: High visceral fat area (greater than 50 percentiles in each sex) was associated with longer cancer-specific survival (P = 0.01) or overall survival (P = 0.03), whereas visceral fat area/subcutaneous fat area ratio showed no influence on survival outcomes. By multivariate analysis adjusted with clinicopathological variables, low visceral fat area was an independent predictor of cancer-specific death and overall death (cancer-specific survival P = 0.004, hazard ratio = 2.19; overall survival P = 0.003, hazard ratio = 2.22), as well as old age (P = 0.01), radical nephrectomy (P = 0.002), high tumor grade (P = 0.01) and the presence of a sarcomatoid component (P < 0.001) in the subgroup analysis of advanced renal cell carcinoma.
CONCLUSION: High visceral fat area might represent a predictor of better prognosis in patients with advanced renal cell carcinomas undergoing nephrectomy.