IL6 and melanoma: Furthermore, low baseline soluble PD-L1 levels have been associated with a superior objective response rate with nivolumab in NSCLC, melanoma, and renal cell cancer [19,20,21], and lower baseline interleukin 6 (IL-6) levels have been associated with longer PFS and OS in NSCLC patients treated with anti-PD-(L)1 therapy [22].