Iacovelli et al. [39] found that lymph node metastases were more frequent in PCs expressing PD-L1 in ≥1% of tumor cells (93% vs. 65%; p = 0.05; n = 32); this difference became significant when considering a ≥5% cut-off for PD-L1 positivity (60% vs. 40%; p = 0.044). The gene discussed is CD274; the disease is neoplasm.