Carcinoembryonic Antigen Test: Understanding Its Role In Cancer Detection

The carcinoembryonic antigen (CEA) test is a type of tumor marker screening used to help detect and monitor certain types of cancer. It plays a key role in cancer diagnosis, staging, and post-treatment follow-up, especially for colorectal, rectal, gastric, and lung cancers.

CEA is a glycoprotein—a substance made of both protein and sugar—that is involved in cell adhesion. It is typically produced during fetal development, mainly by the gastrointestinal tract, pancreas, and liver. While healthy adults usually have low levels of CEA in their blood, elevated levels can be a sign of certain cancers or other conditions.

This test is commonly performed using methods such as chemiluminescent immunoassay (CLIA) or electrochemiluminescence immunoassay (ECLIA). These techniques help detect CEA levels with high accuracy and are frequently used to monitor cancer progression, assess treatment effectiveness, and detect recurrence or metastasis after surgery.

The normal reference range for CEA in CLIA is generally 0–5 ng/mL, while ECLIA typically shows a reference value of up to 3.4 ng/mL. If results exceed these ranges, further diagnostic tests may be necessary under a doctor's guidance to confirm or rule out cancer.

If cancer is diagnosed, treatment options may include surgery, chemotherapy, radiation therapy, or a combination of these. Alongside medical treatment, patients are advised to maintain a healthy lifestyle, manage stress, follow a balanced diet, exercise moderately, and ensure adequate rest to support overall well-being during the treatment process.