This invention provides methods and compositions for diagnosis and treatment of ciliated hepatic foregut cysts (CHFC). In particular, the methods utilize one or more cancer-testis (CT) antigens as a marker for CHFC. The methods can involve the following steps: (a) obtaining a biological sample from a subject (b) measuring the level of a CT antigen (or the level of the CT antigen nucleic acid such as mRNA or DNA) in the sample, and comparing the sample CT antigen level (or the level of the CT antigen nucleic acid such as mRNA or DNA) to the level in normal healthy subjects. A sample CT antigen (or its mRNA or DNA) level in excess of the level in normal healthy subjects indicates CHFC.
