Sensitivity, specificity, percentage of true positives and percentage of true negatives, accuracy, Youden’s J statistic, and positive and negative likelihood ratio values for staining with markers conventionally used for the differential diagnosis of adenocarcinoma (CK7, TTF1, and Napsin A) and squamous cell carcinoma (CK5/6, p40, and p63). The gene discussed is NAPSA; the disease is adenocarcinoma.