CD274 and neoplasm: In contrast to other reports we did however not find a correlation of HPV-status and PD-L1 expression levels (median PD-L1 expression: 35.7% vs. 35.4%, p=0.737) (57), nor did we observe a statistically significant association with overall CTL infiltration (58), albeit there was a trend towards stronger CTL infiltration in patients with strong tumor PD-L1 expression.