Association between leptin level and renal cell carcinoma susceptibility and progression: A meta-analysis.

OBJECTIVES

It is well-documented that obesity participated in the development of renal cell carcinoma (RCC). Leptin is closely associated with obesity. This study is aimed to investigate the relationship between leptin level and RCC susceptibility and progression.

METHODS

A meta-analysis was conducted to explore the association between leptin level and RCC susceptibility and progression. The studies were retrieved from electronic databases during January 1990-September 2017 with keywords. The qualified studies were screened with inclusion and exclusion criteria. A random effects model was applied to calculate the pooled standard mean differences and the corresponding confidence intervals.

RESULTS

Ten studies were finally included in this meta-analysis. The serum leptin level in male RCC was significantly lower than that of in female RCC in overall populations, Asians, and Caucasians while no marked difference was noted between genders in the plasma samples. Plasma leptin level in Stage I-II RCC was significantly higher than that in the Stage III-IV. In addition, no significant difference was observed between following parameters, including RCC and non-RCC, clear and non-clear RCC, Grade I-II and Grade III-IV RCC, M0 and M1 RCC, N0 and N1 RCC, and size <4 cm and size >4 cm RCC. No evidence of publication bias was observed.

CONCLUSIONS

Our findings indicated that serum leptin level was lower in men with RCC than in women with RCC. Leptin level may not be related to the risk and progression of RCC. However, more studies should be performed in the future.