Lung adenocarcinomas are instead positive for nuclear thyroid transcription factor 1 (TTF-1) and Napsin-A and for other cytoplasmic epithelial markers, such as the carcinoembryonic antigen (CEA), the Epithelial Related Antigen (MOC31), EpCam (BEREP4), etc., and rarely for calretinin and podoplanin (D2-40). The gene discussed is CEACAM5; the disease is lung adenocarcinoma.