Does overweight impact on the prognosis of patients with renal cell carcinoma? A single center experience of 683 patients.

BACKGROUND AND OBJECTIVES

An increased incidence of renal cell carcinoma (RCC) in obese patients has been reported by several authors. We investigated the association of body mass index (BMI) with prognosis of patients with RCC.

METHODS

From January 1994 to December 2000, 693 operations for RCC in 683 consecutive patients were performed at our institution. Patients' BMI at operation was evaluated, overall, tumor-specific and progression-free survival was investigated using the Kaplan-Meier method, for multivariate analysis the Cox regression model was used.

RESULTS

Four hundred seventeen patients were males, 266 females. Mean age was 62 years (range 16-88). BMI was available in 609 (89.2%). 371/609 (60.9%) of patients exhibited a BMI greater than 25. After a mean follow-up of 41.5 months, 86 (12.6%) patients died from metastatic RCC, and 29 (4.3%) were alive with metastatic disease. A significant advantage regarding overall (P = 0.015) and progression-free (0.017) but not tumor-specific survival (P = 0.057) was found for patients with a BMI of more than 25 compared to normal-weight patients. In multivariate analysis, BMI showed no significant association with tumor-specific survival.

CONCLUSIONS

Patients with a BMI of more than 25 had a better outcome compared to patients with normal weight in univariate analysis but not multivariate analysis.