Barbareschi et al (18) diagnosed and classified LCLC via the detection of the squamous markers, P63, CK5 and desmocollin 3, the glandular epithelial markers, TTF-1, Napsin A and CK7, and the neuroendocrine markers, Syn, CgA and CD56. The gene discussed is TTF1; the disease is lung large cell carcinoma.