Free DNA and carcinoembryonic antigen serum levels: An important combination for diagnosis of colorectal cancer

Emanuela Flamini, Laura Mercatali, Oriana Nanni, Daniele Calistri, Roberta Nunziatini, Wainer Zoli, Paola Rosetti, Nice Gardini, Arturo Lattuneddu, Giorgio Maria Verdecchia, Dino Amadori

Research output: Contribution to journalArticlepeer-review


Purpose: The identification of new molecular markers for the early detection of colorectal cancer has become an important objective. We compared the sensitivity and specificity of free circulating DNA with that of the more conventional carcinoembryonic antigen (CEA) and evaluated the two markers in combination. Experimental Design: The study was carried out on 75 healthy donors and 75 colorectal cancer patients. Free DNA was determined in serum with quantitative PCR analysis. The diagnostic accuracy of each assay was calculated using receiver operating characteristic (ROC) curves. The diagnostic relevance of the two-marker combination was analyzed by the logistic regression model. Results: Median free DNA concentration was ∼5-fold higher in patients than in healthy donors (P <0.001). The area under the ROC curve was 0.86, and when 12.5 ng/mL was used as cutoff, 81.3% sensitivity and 73.3% specificity were observed for the overall series. As CEA and free DNA provided independent diagnostic information, they were also considered in combination. ROC curve analysis of the combined CEA and free DNA algorithms showed a higher diagnostic capacity (area under the ROC curve, 0.92) than that of markers considered singly, with 84% sensitivity and 88% specificity. Conclusions: Free circulating DNA, especially when used in combination with CEA, represents a potentially useful tool for the diagnosis of early-stage colorectal cancer.

Original languageEnglish
Pages (from-to)6985-6988
Number of pages4
JournalClinical Cancer Research
Issue number23
Publication statusPublished - Dec 1 2006

ASJC Scopus subject areas

  • Cancer Research
  • Oncology


Dive into the research topics of 'Free DNA and carcinoembryonic antigen serum levels: An important combination for diagnosis of colorectal cancer'. Together they form a unique fingerprint.

Cite this