This includes the study of cyst fluids and serum for the characteristic presence of carcinoembryonic antigen (CEA), cancer antigen 19.9 (CA19.9), cancer antigen 72.4 (CA72.4), cancer antigen 15.3 (CA15.3), pancreatic amylase, and mucin antigens, along with other cyst characteristics [11, 12]. The gene discussed is CEACAM5; the disease is cyst.