Normalization of CEA Levels Post-Neoadjuvant Therapy is a Strong Predictor of Pathologic Complete Response in Rectal...

Area of Science:

• Oncology
• Gastroenterology
• Biomarker Research

Background:

• The predictive value of carcinoembryonic antigen (CEA) for pathological complete response (pCR) in rectal cancer remains debated.
• Understanding biomarkers that predict pCR after neoadjuvant chemoradiotherapy (nCRT) is crucial for treatment stratification.

Purpose of the Study:

• To investigate the association between CEA levels and pCR in rectal cancer patients.
• To determine if CEA can serve as a predictive biomarker for pCR post-nCRT.

Main Methods:

• Retrospective analysis of prospectively maintained data from rectal cancer patients undergoing resection post-nCRT.
• Patients categorized into pCR or no-pCR groups based on final pathology.
• CEA levels measured pre- and post-nCRT.

Main Results:

• Post-nCRT CEA levels were significantly lower in patients who achieved pCR (1.7 vs 2.4 μg/L, p < 0.01).
• Low post-nCRT CEA levels independently predicted pCR (OR 1.74, CI 1.06, 3.81).
• CEA normalization from an elevated baseline was a highly significant predictor of pCR (OR 64.8, CI 2.53, 18,371).

Conclusions:

• Post-nCRT CEA levels are a significant predictor of pCR in rectal cancer.
• Normalization of CEA after nCRT is a strong indicator of pCR.