CEA reduction after cryotherapy for liver metastases from colon cancer predicts survival

Serum carcinoembryonic antigen (CEA) levels in 33 Australian patients with hepatic metastases from colorectal cancer were measured before and after treatment with hepatic cryotherapy and intra-arterial chemotherapy. Pre-operative and monthly postoperative CEA measurements were made and the lowest postoperative reading was recorded as a percentage fall from the pre-operative level. There was a highly significant association between the maximum percentage fall in CEA and survival. A 50% increase in the maximum percentage fall in CEA level was associated with one-tenth the risk of death (95% CI RR 0.03 to 0.32, Cox regression). It is estimated that an increase in the maximum percentage fall in CEA of 50% from 25 to 75% was associated with an increase in the median survival from 240 days to over 2 years.