The comparative analysis of TTF-1 vs. Napsin-A for their sensitivity and specificity for the distinction of pulmonary adenocarcinomas from other tumors (except thyroidal cancers) in a subset of 4567 cancers with data for both TTF-1 and Napsin-A revealed a higher sensitivity for TTF-1 (94.1%) while the specificity was higher for Napsin-A (97.8%, Table 3). The gene discussed is NAPSA; the disease is cancer.