What test is used to monitor colorectal cancer?

The carcinoembryonic antigen (CEA) test is specifically used to monitor colorectal cancer. CEA is a type of glycoprotein that is present in higher levels in some individuals with colorectal cancer, making it a useful biomarker in the diagnosis and management of this condition. After a patient has been treated for colorectal cancer, CEA levels can be monitored to check for recurrence of the disease. An increase in CEA levels may indicate that cancer has returned or that there are issues with the treatment efficacy.

In contrast, CA-125 is primarily associated with ovarian cancer and is not a marker for colorectal cancer. The complete blood count (CBC) is a general test that provides information about overall health and can indicate various conditions but is not specific for colorectal cancer. Similarly, PSA is a test used mainly to screen for prostate cancer and is not relevant in the monitoring of colorectal cancer. Hence, CEA is the appropriate test to monitor colorectal cancer progression or recurrence.