High serum carcinoembryonic antigen concentration in patients with colorectal liver metastases is associated with poor cell-mediated immunity, which is predictive of survival.

BACKGROUND: Carcinoembryonic antigen (CEA) inhibits lymphocyte function and patients with cancer have lower cell-mediated immunity (CMI) than the normal population. To test this association an investigation was made of the relationship between CMI score, CEA level and survival.
METHODS: CEA level, CMI score and other variables were compared with the survival time of 109 patients with colorectal liver metastases using Cox regression analysis.
RESULTS: There was a significant association between CMI and CEA categories (P = 0.04, chi 2 test). The odds of patients with normal CMI having a CEA level in the upper quartile observed for all patients were 22 per cent of those of patients with depressed CMI (odds ratio 0.22 (95 per cent confidence interval (c.i.) 0.03-0.90), mid-P corrected). The median survival time of patients with normal CMI scores was 943 days compared with 488 days for those with depressed CMI (P = 0.03, log rank test; P = 0.04, Peto). The mortality risk of patients with normal CMI at entry to the study was, in the first 2 years of treatment, 40 per cent of that of patients with depressed CMI (95 per cent c.i. for relative risk 0.20-0.82, Cox regression).
CONCLUSION: In patients with colorectal hepatic metastases, CMI is predictive of survival and a raised serum CEA level is associated with depressed CMI.