Almost exclusively a tumor specific antigen, with the exception of the testes and the placenta.
Expressed in 30-50% of non-small cell lung cancers.
Associated with increased expression with increasing stage in non-small cell lung cancer.
Overexpressed more often is squamous cell carcinoma of the lung than in adenocarcinoma of the lung.
Detected in tumor tissue by the use of reverse transcription polymerase chain reaction.