The impact of carcinoembryonic antigen flare in patients with advanced colorectal cancer receiving first-line chemotherapy.
BACKGROUND
Carcinoembryonic antigen (CEA) flare may have a favourable response to chemotherapy, but its impact on survival is unknown. This study aimed to evaluate the incidence of CEA flare and its impact on objective response rate (ORR), progression-free survival (PFS) and overall survival (OS).


METHODS
Patients with histologically proven advanced colorectal cancer undergoing first-line chemotherapy with three or more serial CEA measurements (one at baseline and two or more during treatment) were included. Patients were grouped according to CEA kinetic as flare (F), decreasing CEA, normal baseline CEA, stable CEA and increasing CEA (I).


RESULTS
From January 2000 to February 2008, 837 patients were screened of whom 670 were eligible. CEA flare occurred in 78 (11.6%) patients. On multivariate analysis, compared with patients with increasing CEA, patients with CEA flare had a significantly better ORR [I versus F: 11% versus 73%; risk ratio (RR): 27.96; 95% confidence interval (CI): 9.55-81.88; P < 0.001], PFS (median 3.1 versus 8.3 months; RR: 0.38; 95% CI: 0.26-0.56; P < 0.001) and OS (median 10.9 versus 17.7 months; RR: 0.53; 95% CI: 0.34-0.82; P < 0.001).


CONCLUSIONS
Compared with patients with rising CEA, flare was an independent favourable predictive and prognostic factor for tumour response and survival.
Strimpakos
A S
AS
Department of Medicine, Royal Marsden Hospital, London and Surrey, UK.
Cunningham
D
D
Mikropoulos
C
C
Petkar
I
I
Barbachano
Y
Y
Chau
I
I
D000230:Adenocarcinoma / Q000097:blood* / Q000188:drug therapy* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D002272:Carcinoembryonic Antigen / Q000097:blood*; D015179:Colorectal Neoplasms / Q000097:blood* / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000077146:Irinotecan; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D011379:Prognosis; D015996:Survival Rate; D055815:Young Adult
D002272:Carcinoembryonic Antigen; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D000077146:Irinotecan; D002166:Camptothecin