Banki F et al. - In a study to compare the sensitivity and specificity of carcinoembryonic antigen (CEA) and plasma DNA in the diagnosis of recurrent esophageal cancer, it was found that elevated plasma DNA is an extremely reliable indicator of the presence of recurrent disease, and, in the majority of pts, it rises before clinical evidence of recurrence. In contrast, a normal CEA should be interpreted cautiously, because it does not exclude recurrent disease Methods
Plasma DNA was measured using polymerase chain reaction in 45 pts with esophageal cancer and 44 asymptomatic volunteers
The 95th percentile (19 ng/mL) in the volunteers was used to define normal
39 pts had localized cancer and underwent resection and 6 had disseminated disease at operation
Plasma DNA was measured preoperatively in all pts, with serum CEA measured in 31
Plasma DNA was measured sequentially during followup in 21 pts, including 7 who developed recurrence
CEA was measured in 14 of 21 pts who had sequential plasma DNA measured and in 6 of 7 pts with recurrence
CEA levels greater than 5.0 ng/mL were used as cut-off
Results
Plasma DNA was more sensitive than CEA for detecting unresectable esophageal cancer (100% vs 40%), but it had a lower specificity (22% vs 89%)
Positive predictive value (19% vs 40%) and negative predictive value (100% vs 89%) were similar for plasma DNA and serum CEA, respectively
Plasma DNA was more sensitive than CEA in detecting recurrent esophageal cancer (100% vs 33%)
Specificity and positive predictive values were 100% for both tests, but the negative predictive values were higher for plasma DNA
Plasma DNA rose before there was clinical evidence of recurrence in 67% vs only 17% for CEA
See all
