Carcinoembryonic antigen (CEA) is a primary prognostic marker and can detect colorectal cancer (CRC) recurrence; however, it has low sensitivity.  Carbohydrate antigen 19-9 (CA 19-9) can be used as a supplemental tumour marker along with CEA.  The purpose of this study was to determine whether preoperative CA 19-9 added to CEA helped predict long-term prognosis and whether follow-up CA 19-9 added to CEA had additional benefits in diagnosing the recurrence of CRC.


 Data on demographics, preoperative and follow-up CEA and CA 19-9 levels, recurrence and survival were obtained and analysed with respect to tumour marker levels to ascertain their prognostic and diagnostic values.


 The 5-year relapse-free survival rates were 72.2% ± 0.8%, 52.5% ± 2.2%, 55.5% ± 3.2% and 32.1% ± 2.3% in the normal CEA and CA 19-9, high CEA, high CA 19-9, and high CEA and high CA 19-9 groups, respectively (all P < 0.001).  Patients whose elevated CEA or CA 19-9 levels reduced to normal levels had better survival outcomes than those with postoperatively elevated levels.  Elevated follow-up CA 19-9 and CEA levels were related to higher incidences of distant metastasis (CA 19-9, 14.0% vs. 23.1%, P = 0.004; CEA, 12.6% vs. 30.1%, P < 0.001) but not to local recurrence.  Combined follow-up CEA and CA 19-9 increased the sensitivity for recurrence to 31.4%, with a 5% difference from the sensitivity of CEA alone.  CA 19-9 is a valuable prognostic and diagnostic marker for CRC when used adjunctively with CEA and can be a supplementary marker with CEA to improve sensitivity, especially with elevated preoperative CA 19-9.
CEA
Carbohydrate antigen 19-9 (CA 19-9) can be used as a supplemental tumour marker along with CEA.  The purpose of this study was to determine whether preoperative CA 19-9 added to CEA helped predict long-term prognosis and whether follow-up CA 19-9 added to CEA had additional benefits in diagnosing the recurrence of CRC.


 Data on demographics, preoperative and follow-up CEA and CA 19-9 levels, recurrence and survival were obtained and analysed with respect to tumour marker levels to ascertain their prognostic and diagnostic values.


 The 5-year relapse-free survival rates were 72.2% ± 0.8%, 52.5% ± 2.2%, 55.5% ± 3.2% and 32.1% ± 2.3% in the normal CEA and CA 19-9, high CEA, high CA 19-9, and high CEA and high CA 19-9 groups, respectively (all P < 0.001).  Patients whose elevated CEA or CA 19-9 levels reduced to normal levels had better survival outcomes than those with postoperatively elevated levels.  Elevated follow-up CA 19-9 and CEA levels were related to higher incidences of distant metastasis (CA 19-9, 14.0% vs. 23.1%, P = 0.004; CEA, 12.6% vs. 30.1%, P < 0.001) but not to local recurrence.  Combined follow-up CEA and CA 19-9 increased the sensitivity for recurrence to 31.4%, with a 5% difference from the sensitivity of CEA alone.  In the subgroup with high preoperative CA 19-9 levels, sensitivity increased by 18.2% overall.


 CA 19-9 is a valuable prognostic and diagnostic marker for CRC when used adjunctively with CEA and can be a supplementary marker with CEA to improve sensitivity, especially with elevated preoperative CA 19-9.
CA 19-9