Pre- and postoperative uses of CEA.

CEA plasma levels obtained prior to definitive surgery in patients with colorectal cancer in our hands have predictive ability. An elevated CEA greater than 2.5 ng/ml recorded by our laboratory means an increased risk of subsequent local recurrence or of later metastatic disease. The question as to whether or not this is additive as a prognostic variable when tested against careful histopathological staging remains. As a monitor, CEA will detect recurrence. Again, the problem as to how accurate this is remains. If we use two consecutive elevations of plasma CEA greater than 2.5 ng/ml as a criteria, we encounter about 15% false positives which must be weighed against finding disease significantly earlier in about one-third of the patients followed. Our data for second-look procedures indicate clearly that when used in patients with an elevated CEA laparotomy may be useful and further studies showed the presence of disease in 11 of 14 patients with an elevation following surgery for two consecutive tests were greater than 2.5 ng/ml. Two were operable. The significance of these findings is described.