PDCD1 and nasopharyngeal carcinoma: In advanced nasopharyngeal carcinoma (NPC), the progression-free survival (PFS) of PD-1 inhibitor immunotherapy alone was 4.7 months and the 6-month PFS rate was 50% [14], while PD-1 inhibitors combined with chemotherapy achieved an objective effective rate of up to 91%, a disease control rate as high as 100%, and an 86% 6-month PFS [15].