Inflammatory markers that are increased in obesity, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were associated with increased risk of incident ccRCC, but whether these inflammatory pathways play a causal role in the pathogenesis of ccRCC has not been definitively established [114,115]. Here, IL6 is linked to nonpapillary renal cell carcinoma.