PDCD1 and melanoma: In melanoma, low IL-6 or high IL-17 at baseline were associated with severe irAEs following anti-CTLA-4 blockade while an aggregated CYTOX score consisting of 12 cytokines and chemokines, including IL-13, had a modest predictive performance (AUC = 0.68–0.70) for severe irAEs in patients treated with anti-PD-1 alone or in combination with anti-CTLA-4 inhibitors (9, 63, 64).