Case Report: CEA Elevation Can Be a Marker of Increased Inflammation During Treatment with Oxaliplatin.

Oxaliplatin is a platinum-based chemotherapy that is an integral part of several regimens for colorectal cancer. We present the case of a patient, a 58-year-old male, who had initially presented aged 56 years with rectal bleeding for several months. His serum carcinoembryonic antigen (CEA) level at the time of diagnosis was 4.6 ng/ml. His CEA level increased significantly during oxaliplatin-based chemotherapy and declined to a near normal level after completion of therapy. There was no evidence of disease during this time and he remains disease-free. Oxaliplatin has been shown to cause an inflammatory response which appears to be one of the mechanisms of toxicity and high CEA levels have been correlated with increased inflammation. We postulate that this patient's rising CEA level was secondary to an inflammatory response to oxaliplatin-based therapy, which is further supported by the subsequent decrease after completion of chemotherapy. To our knowledge, this is the first published case of oxaliplatin-induced rising CEA level.