Limitations of Carcinoembryonic Antigen (CEA) Testing in Oncology

Established Indications for CEA

• The American Society of Clinical Oncology (ASCO) recommends CEA only for colorectal cancer: pre‑operative staging, postoperative surveillance (every 3 months for stage II‑III disease), and monitoring of metastatic disease during systemic therapy【1】【2】.
• According to ASCO, CEA exhibits high specificity but very low sensitivity for colorectal cancer screening, rendering it unsuitable for cancer detection in asymptomatic general populations【1】【2】.
• For breast cancer, CEA may be employed solely to monitor metastatic disease during active treatment; it is not indicated for screening or initial diagnosis【3】.

Lack of Utility in Renal Cell Carcinoma (Kidney Cancer)

• CEA has no validated role in the diagnosis, staging, or surveillance of renal cell carcinoma and should be omitted from work‑up algorithms for suspected kidney cancer【1】【2】.

Non‑Specific Elevations and False‑Positive Sources

• Elevated CEA levels can arise from benign conditions such as inflammatory bowel disease, chronic liver disease, pancreatitis, and tobacco use, leading to false‑positive results【3】.
• Age‑related increases in CEA are common, and the marker may be raised in multiple non‑malignant states, further limiting its specificity【3】.

Recommended Diagnostic Approach When Kidney Cancer Is Suspected

• In patients with a suspected renal malignancy, the preferred initial evaluation is contrast‑enhanced CT or MRI of the abdomen and pelvis; CEA testing should not be ordered【3】.

Evidence strength: All statements above are derived from guideline recommendations (ASCO) or expert consensus; specific grading (e.g., Class I, Level A) was not provided in the source material.