Serum CA 19-9 as a marker of resectability and survival in patients with potentially resectable pancreatic cancer treated with neoadjuvant chemoradiation.
OBJECTIVE
The role of carbohydrate antigen (CA) 19-9 in the evaluation of patients with resectable pancreatic cancer treated with neoadjuvant therapy prior to planned surgical resection is unknown. We evaluated CA 19-9 as a marker of therapeutic response, completion of therapy, and survival in patients enrolled on two recently reported clinical trials.


METHODS
We analyzed patients with radiographically resectable adenocarcinoma of the head/uncinate process treated on two phase II trials of neoadjuvant chemoradiation. Patients without evidence of disease progression following chemoradiation underwent pancreaticoduodenectomy (PD). CA 19-9 was evaluated in patients with a normal bilirubin level.


RESULTS
We enrolled 174 patients, and 119 (68%) completed all therapy including PD. Pretreatment CA 19-9 <37 U/ml had a positive predictive value (PPV) for completing PD of 86% but a negative predictive value (NPV) of 33%. Among patients without evidence of disease at last follow-up, the highest pretreatment CA 19-9 was 1,125 U/ml. Restaging CA 19-9 <61 U/ml had a PPV of 93% and a NPV of 28% for completing PD among resectable patients. The area under the receiver-operating characteristics curve of pretreatment and restaging CA 19-9 levels for completing PD was 0.59 and 0.74, respectively. We identified no association between change in CA 19-9 and histopathologic response (P = 0.74).


CONCLUSIONS
Although the PPV of CA 19-9 for completing neoadjuvant therapy and undergoing PD was high, its clinical utility was compromised by a low NPV. Decision-making for patients with resectable PC should remain based on clinical assessment and radiographic staging.
Katz
Matthew H G
MH
Department of Surgery, The University of California, Orange, CA, USA. katzmh@uci.edu
Varadhachary
Gauri R
GR
Fleming
Jason B
JB
Wolff
Robert A
RA
Lee
Jeffrey E
JE
Pisters
Peter W T
PW
Vauthey
Jean-Nicolas
JN
Abdalla
Eddie K
EK
Sun
Charlotte C
CC
Wang
Huamin
H
Crane
Christopher H
CH
Lee
Jeffrey H
JH
Tamm
Eric P
EP
Abbruzzese
James L
JL
Evans
Douglas B
DB
D000230:Adenocarcinoma / Q000097:blood / Q000401:mortality / Q000628:therapy; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018395:CA-19-9 Antigen / Q000097:blood*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000401:mortality* / Q000628:therapy; D016577:Pancreaticoduodenectomy; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
D018395:CA-19-9 Antigen