Does overweight influence the prognosis of renal cell carcinoma? Results of a multicenter study

Abstract

Objectives: To assess the impact of overweight on prognosis of renal cell carcinoma patients. Patients And Methods: A total of 2030 patients who underwent surgery for renal cell carcinoma from 1990 to 2011 in three University Medical Centers were included in this retrospective analysis. For all patients, height and weight measurements at the time of diagnosis were available for review. The median (mean) follow up was 56.6 months (66.0 months). Results: A low body mass index was significantly associated with poor tumor differentiation, histology, microscopic vascular invasion and metastatic disease at the time of diagnosis. A lower-than-average body surface area -stratified according to the European average for men (1.98 m 2 ) and women (1.74 m 2 ) -was significantly related to older age, poor tumor differentiation, the histological subtype and microscopic vascular invasion. In addition, a low visceral fat area calculated in a subgroup of 133 evaluable patients was associated with a higher risk of advanced disease (pT3-4 and/or N/M+) at diagnosis. The tumor-specific 5-year survival rate was 71.3, 78.7 and 80.1%, for patients with a body mass index of, <25, 25-30 and Ն30. Multivariate analysis confirmed body mass index as an independent prognostic factor. Conclusion: Our findings suggest that overweight represents an independent prognostic factor in renal cell carcinoma patients. Further research should address the question of why obese people have a higher incidence of renal cell carcinoma, but at the same time a significantly better prognosis than other patients, particularly in the case of localized disease.

Association between visceral and subcutaneous adiposity and clinicopathological outcomes in non-metastatic clear cell renal cell carcinoma

“…Furthermore, regardless of BMI, women appear to have higher levels of SFA and fat mass than men. 8,10,16,17,28 Similarly, in the current study the correlation between BMI and VFA (r = 0.542) was relatively weak when compared to that of BMI and SFA (r = 0.804) and BMI and TFA (r = 0.846). In addition, women had higher SFA but lower VFA than men, but did not differ from men with regard to BMI or TFA.…”

“…In a recent metaanalysis, higher BMI was inversely associated with mortality (HR 0.57; 95% CI 0.43-0.76 when comparing the highest and the lowest BMI). 3,16 Visceral adiposity has been inconsistently associated with clinicopathological characteristics of RCC. Naya and colleagues reviewed 117 male patients treated with nephrectomy for ccRCC.…”

“…13 Similarly, Steffens and colleagues noted that a higher than median VFA was associated with lower tumour stage, whereas patients with low VFA suffered more frequently from advanced disease at diagnosis. 16 More recently, Zhu and colleagues evaluated the association between visceral obesity and Furhman grade in patients with clinical T1a RCC. Unlike previous reports, they demonstrated that high VFA% was associated with a higher grade of RCC.…”

“…4,12 While the reported effects of BMI on RCC have been uniform, reports concerning the effect of visceral adiposity on the pathological and clinical outcomes of RCC are inconsistent. [13][14][15][16][17] Moreover, most previous studies evaluating the predictive value of visceral fat in non-metastatic RCC were conducted among Asian populations, which have relatively lower BMIs than Western populations, and may display a different relationship between BMI and body fat. 18,19 The aim of the current study was to evaluate whether visceral fat area (VFA) and subcutaneous fat area (SFA) were related to tumour characteristics and treatment outcomes in a group of surgically treated, non-metastatic, clear cell RCC (ccRCC) patients from the United States.…”

Editorial Comment to Does overweight influence the prognosis of renal cell carcinoma? Results of a multicenter study

“…This article clearly showed evidence that obesity is a fair prognostic factor for renal cell carcinoma patients with organ‐confined disease . Such findings have been accumulating recently enough to convince somewhat mysterious phenomenon.…”