MTOR and Hyponatremia: In a large series of 1,661 mRCC patients receiving VEGF or mTOR targeted therapy as first-line treatment, hyponatremia (<135 mmol/L) was associated with a significantly lower OS (7.0 vs. 20.9 months), time to treatment failure (2.9 vs. 7.4 months), and DCR (54.9% vs. 78.8%) compared with normonatremia (p < 0.0001 for all comparisons) (15).