NCAM1 and infection: New neuroendocrine markers such as PGP9.5 and INSM1 have also been proven to have high positivity rates in cervical SCNEC, and even higher specificity and sensitivity than traditional markers (CD56, CgA, Syn).[8,9] Cervical neuroendocrine carcinoma is associated with HPV infection, especially with a high prevalence of HPV16/18 infections, most of which show positive P16 staining.[10] In 4 cases, P16 was diffusely and strongly expressed.