Clinically relevant tumors with near complete absence of PAX8 staining (< 1%) included for example all subtypes of breast cancers, gastric adenocarcinoma, prostatic adenocarcinoma, hepatocellular carcinomas, cholangiocarcinoma, gallbladder adenocarcinoma, pulmonary adenocarcinoma, neuroendocrine neoplasms, and small cell carcinomas of various sites. The gene discussed is PAX8; the disease is gallbladder adenocarcinoma.