AVPR2 and head and neck squamous cell carcinoma: The results showed that there were 128 cases of C1, 379 cases of C2, 2 cases of C3, 2 cases of C4, 3 cases of C6 and no cases of C5, and AVPR2 expression was related to different immune subtypes in HNSCC (P = 8.37E-03) (Fig. 4).