NCAM1 and squamous cell carcinoma: NSCLC with immunopositivity for LCNEC markers (CD56, Chromogranin or Synaptophysin), adenocarcinoma markers (TTF-1 or NapsinA) or squamous cell carcinoma markers (p40, p63 or CK5/6) is excluded under the current criteria and now reclassified as either a neuroendocrine tumor, adenocarcinoma with solid pattern or nonkeratinizing squamous cell carcinoma, respectively, according to the new 2015 WHO classification [1, 2].