CARCINOEMBRYONIC ANTIGEN
Recently, studies have been made of the use and limitations of CEA in diagnosis, detection, and treatment monitoring of patients with pancreatic cancer and related diseases, including acute and chronic pancreatitis. in cancer of the pancreas (1). Subsequently, in an attempt to study cell mediated immunity t o CEA, Lejtenyi, Freedman, and Gold looked for but did not find evidence of lymphocyte transformation to CEA in a few patients with pancreatic cancer (2). In 1969, Thomson and co-workers described a serum assay for CEA but reported it positive in only one patient with carcinoma of the pancreas and metastases (3). This laboratory reported 100% CEA positivity in the first 13 cases studied (4), and subsequently 85% positivity in 28 cases (5). A high percentage of CEA positivity in patients with pancreatic cancer has been widely confirmed (6)(7)(8)(9). Just as with colon cancer, however, it became apparent that the high frequency of positivity was related, in part at least, to the fact that many pancreatic cancer Gold and Freedman first demonstrated tumor "specific" carcinoembryonic antigens