Serum and tissue CEA in colorectal cancer: clinical relevance.

Purpose: This article is an analysis of the information derived from the determination of tumor-tissue concentration of CEA in patients with colorectal cancer. To ascertain the relationship between tumor marker content with the histologic aspects and serologic levels of CEA of this neoplam.
Materials and Methods: 136 patients with colorectal adenocarcinoma and 41 with colorectal benign processes are analyzed and followed during an average time of 27 months. The CEA of the serum were obtained preoperatively and postoperatively and measured by radioimmunoassay (RIA). Tissular CEA levels were determined with RIA. The histological characteristics are analyzed (Dukes classification, grade of differentiation, index of atypia, microscopic vascular and lymphatic involvement.
Results: 1) The cut off point of the tissular CEA with the best sensitivity and specificity for the diagnosis of normal mucosa is 386 ng/mg and for tumoral tissue is 1160 ng/mg. 2) There is no correlation between tissue and serologic CEA value. 3) The tissular level of CEA have a significant statistical correlation with Dukes stage (p < 0.003); other histological characteristics were no significative. 4) There are significant statistical correlations between serologic CEA and relapse but no with survival rates.
Conclusions: 1) Serologic CEA levels depend on numerous factors. 2) There aren't correlations between preoperative serologic levels and tissular CEA levels. 3) Tissular CEA do not predict what patients will have an elevated serologic CEA level in relapse.