Fig. 4.

Tumor PD-L1 assessed on lymph node (LN) metastases and skin/subcutaneous (SC) metastases and its association with survival outcome of the first PD-1-based ICI therapy. (A) Frequencies of different types of tissue samples used for tumor PD-L1 quantification in the cohort of patients assessed on metastases; (B) frequencies of tumor PD-L1 expression determined on LN versus skin/SC metastases. (C, D) Kaplan–Meier survival curves showing progression-free (PFS) and overall survival (OS) dependent on tumor PD-L1 expression assessed on LN (C) and skin/SC (D) metastases. (E, F) Multivariate Cox regression analysis of PFS and OS considering tumor PD-L1 expression determined on LN (E) and skin/SC (F) metastases.