The role of half-life of carcinoembryonic antigen (CEA) in prognosis prediction of colorectal cancer patients with preoperatively elevated CEA.
OBJECTIVE
Carcinoembryonic antigen (CEA) monitoring plays an important role in the management of malignancies, especially in colorectal cancer (CRC). The half-life (T1/2) of CEA has also been applied as a new predictor in the surveillance of some malignancies. This study was to examine the preoperative and early postoperative levels of CEA in CRC patients and calculate postoperative T1/2 of CEA to evaluate its potential role in prognosis prediction.


METHODS
In this retrospective study, 98 CRC patients who had preoperatively elevated levels of CEA (>or=5 microg/L) and serum CEA surveillance after radical operation were included. Postoperative T1/2 of CEA was calculated. Its correlation to prognosis was analyzed.


RESULTS
Of the 98 patients, 21 had local recurrence or distant metastasis (recurrence group), 77 had no recurrence (non-recurrence group). The median value of preoperative CEA level was significantly higher in recurrence group than in non-recurrence group (23.9 microg/L vs. 12.3 microg/L, P=0.010); the median value of postoperative T1/2 of CEA was significantly longer in recurrence group than in non-recurrence group (6.2 days vs. 4.7 days, P=0.042); the later the TNM stage was, the poorer the prognosis was (P<0.001). The 3-year disease-free survival (DFS) rate and overall survival (OS) rate were significantly higher in the patients with postoperative T1/2 of CEA of <4.8 days than in those with T1/2 of >or=4.8 days (87% vs. 66%, P=0.017; 90% vs. 80%, P=0.032). The patients at earlier TNM stage had survival benefits both in DFS and OS: the 3-year DFS rates in stage I, II, and III patients were 100%, 93%, and 55%, respectively (P<0.001); the 3-year OS rates were 100%, 98%, and 77%, respectively (P=0.192). In Cox regression analysis, both TNM stage and postoperative T1/2 of CEA were confirmed to be independent prognostic factors of CRC patients with preoperatively elevated CEA level.


CONCLUSIONS
In addition to TNM stage, the T1/2 of CEA may be an independent prognostic factor in CRC patients with preoperatively elevated CEA level. The patients with longer T1/2 of CEA after radical operation have poorer prognosis.
State Key Laboratory of Oncology in South China, Guangzhou, Guangdong 510060, P. R. China.
Shu-Qiang
SQ
Yuan
Zhi-Wei
ZW
Zhou
De-Sen
DS
Wan
Gong
G
Chen
Zhen-Hai
ZH
Lu
Guo-Qiang
GQ
Wang
Zhi-Zhong
ZZ
Pan
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002272:Carcinoembryonic Antigen / Q000378:metabolism*; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000401:mortality* / Q000473:pathology; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D012189:Retrospective Studies
D002272:Carcinoembryonic Antigen