Open AccessA cross‐sectional study comparing a blood test for methylated BCAT 1 and IKZF 1 tumor‐derived DNA with CEA for detection of recurrent colorectal cancer
Author(s) -
Young Graeme P.,
Pedersen Susanne K.,
Mansfield Scott,
Murray David H.,
Baker Rohan T.,
Rabbitt Philippa,
Byrne Susan,
Bambacas Libby,
Hollington Paul,
Symonds Erin L.
Publication year - 2016
Publication title -
cancer medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 53
ISSN - 2045-7634
DOI - 10.1002/cam4.868
Subject(s) - medicine , mcnemar's test , carcinoembryonic antigen , colorectal cancer , blood test , gastroenterology , guideline , odds ratio , oncology , cancer , pathology , statistics , mathematics
Recurrence will develop in 30–50% of colorectal cancer ( CRC ) cases despite apparent clearance following treatment. Carcinoembryonic antigen ( CEA ) is the only guideline‐recommended blood test for monitoring cases for recurrence, but its sensitivity and specificity are suboptimal. This observational study compared a novel 2‐gene (methylated BCAT 1 and IKZF 1 DNA ) blood test with CEA for detection of recurrent CRC . We conducted a paired comparison of the BCAT 1 / IKZF 1 test with CEA (cut‐off 5 ng/ mL ) in blood from patients in remission after treatment for primary CRC and undergoing surveillance. Blood collected in the 12 months prior to or 3 months after complete investigational assessment of recurrence status were assayed and the results compared by McNemar's test. Of 397 patients enrolled, 220 underwent satisfactory assessment for recurrence and 122 had blood testing performed within the prescribed period. In 28 cases with recurrent CRC , CEA was positive in 9 (32%; 95% CI 16–52%) compared to 19 (68%; 95% CI 48–84%) positive for methylated BCAT 1/ IKZF 1 ( P = 0.002). All samples that were CEA positive were also BCAT 1/ IKZF 1 positive. In 94 patients without clinically detectable recurrence, CEA was positive in 6 (6%, 95% CI 2–13%) and BCAT 1/ IKZF 1 in 12 (13%, 95% CI 7–21%), P = 0.210. The odds ratio of a positive CEA test for recurrence was 6.9 (95% CI 2–22) compared to 14.4 (5–39) for BCAT 1/ IKZF 1 . The BCAT 1/ IKZF 1 test was more sensitive for recurrence than CEA and the odds of recurrence given a positive test was twice that of CEA . The BCAT 1/ IKZF 1 test should be further considered for monitoring cases for recurrence.