Subsequently, we employed a visual cutpoint (defined as the lowest expressing case where the signal is discernably present and specific above the background noise) to define CD200 tumor positivity; 29.7% of NSCLC cases and 33.3% of lung large cell neuroendocrine carcinoma (LCNEC) cases were found positive for CD200 within the tumor compartment (Figure 1A,B). Here, CD200 is linked to pulmonary large cell neuroendocrine carcinoma.