CARCINOEMBRYONIC ANTIGEN IN 228 PATIENTS WITH CARCINOMA OF T H E LUNG K . G . V I N C E N T , MD,* T. M. C H U , PHD,+T. B. FERGEN,* A N D M. OSTRANDER~
Two hundred and twenty-eight patients who were treated for carcinoma of the lung were followed a n d their plasma CEA levels assessed at intervals during the course of the disease. In addition, plasma samples were taken from 487 healthy blood donors for comparison as a control. CEA assay is not selective or specific enough, at this time, to be used for screening purposes even though 68% of the patients who have lung cancer will have a n elevated concentration of CEA regardless of the histological cell type. In patients with plasma levels of CEA above 15 ng/ml the prognosis is uniformly poor. CEA in the authors’ view does have value as a prognostic marker capable of suggesting the successful resection of a tumor and to a lesser degree confirming the clinical objective response to the radiotherapy or chemotherapy. It was found that the presence of CEA was not necessarily related to the volume of the tumor or the site of organ metastasis, but reflects the metabolic properties and characteristics of the individual tumor as it occurs in the patient. Cancer 36:2069-2076, 1975.
11E I N C R E A S I N G I N C I D E N C E OF L U N G CANCER
with its relatively poor response to present means of therapy provides the clinician with a formidable problem. A means of detecting the presence of a lung tumor at an early clinical stage or the means of assessing the completeness of a surgical resection or the effectiveness of radiation or chemotherapy would be of infinite value. A carcinoembryonic antigen (CEA) thought to be specific for adenocarcinoma of the colon was described by Gold and Freedman5 in 1965. Subsequent studies have demonstrated that CEA concentrations appear to be elevated in the presence of malignant tumors other than those of gastrointestinal A technique of radioimmunoassay capable of detecting plasma levels of CEA in nanogram range was described by Thomson13 in 1969. Hansen6 in 1970 described the use of zirconylphosphate gel, the method that we have used for radioimmunoassay of CEA.
Many investigators have conducted clinical evaluations of CEA during the past 4 years, 126.96.36.199.11,15 We believe it is now possible to give some appraisal of the value of CEA in the assessment of the lung cancer patient. In this investigation we are looking to answer, in part, the following questions: 1) Based on data from various control population groups, what concentration of CEA should be regarded as normal? 2) Can CEA concentrations be used to screen a high risk population for patients that may be developing lung cancer and what prognostic clinical significance, if any, can be associated with the initial CEA concentration found in the lung cancer patient? 3) Can the progress of the disease or the remission of the disease be followed with CEA being used as a marker or as a monitor? 4) Is the concentration of CEA related to the tumor volume or to specific sites of metastasis? MATERIALS A N D METHODS
Irom the Roswell Park hlemorial Institute, Buffalo, NY 14203. * Chief. 1)epartment of ‘l‘horacic Surgery. ’ .\ssocxitr (:hief