PD-0022 - Decline in CA19-9 during chemotherapy predicts survival in four independent cohorts of patients with inoperable cholangiocarcinoma.

Date 27 June 2014
Event World GI 2014
Session Poster discussion session IV - Miscellaneous
Topics Biomarkers
Hepatobiliary Cancers
Presenter Mie Grunnet
Citation Annals of Oncology (2014) 25 (suppl_2): ii5-ii13. 10.1093/annonc/mdu164
Authors M. Grunnet1, I. Christensen2, U. Lassen1, L.H. Jensen3, M. Lydolph4, J. Knox5, M. McNamara5, M. Jital6, J. Bridgewater6, J. Valle7, M. Mau-Sørensen1
  • 1Rigshospitalet - Copenhagen University Hospital, Copenhagen/DK
  • 2The Finsen Laboratory, Rigshospitalet, Copenhagen/DK
  • 3Vejle Hospital, Vejle/DK
  • 4Dept. Of Clinical Biochemistry and Immunology, National Institute for Health Data and Disease Control, Copenhagen/DK
  • 5Dept. of Medical Oncology Princess Margaret Hospital, Toronto/CA
  • 6University College London Cancer Institute, London/UK
  • 7University of Manchester, Dept. Medical Oncology, The Christie Hospital, NHS Foundation Trust, Manchester/UK

Abstract

Introduction

Plasma carbohydrate associated antigen (CA19-9) has been approved by the FDA as a tumor biomarker for the monitoring of treatment effect in pancreatic cancer. However, the value of plasma CA19-9 as a biomarker of response to chemotherapy in cholangiocarcinoma is unclear. The aim of this study was to determine if a decline in CA19-9 (CA19-9 response) during chemotherapy is predictive of survival in patients with inoperable cholangiocarcinoma.

Methods

Patients with inoperable cholangiocarcinoma treated at a University Hospital were consecutively included in a training set (n = 212). Three validation data sets were established including patients from 1) a Danish County Hospital (n = 60), 2) a Canadian cohort (n = 196) and 3) the randomized ABC-02 trial (n = 410). Patients with a baseline CA19-9 level above 1.5 times the upper limit of normal and at least one CA19-9 value measured ten to twelve weeks after the start of chemotherapy were included in the analysis. Multivariate Cox regression analyses were performed.

Results

Patients meeting the criteria to be included in the analyses were 46 in the training set and 27, 52 and 128 in the three validation sets respectively. Multivariate analysis included radiological response, performance status and age. A hazard ratio (HR) of 0.77 (95%CI: 0.63-0.93, p = 0.008) for death in CA19-9 responders (CA19-9 as a continuous variable) was reached in the training set. The predictive value of CA 19-9 response with regard to overall survival was confirmed in all three validation data sets (HR = 0.77, 95%CI: 0.59-0.99, p = 0.04, HR= 0.79; 95%CI: 0.65-0.96, p = 0.02 and HR = 0.88; 95%CI: 0.80-0.98 p = 0.02 respectively).

Conclusion

CA19-9 response seen 10-12 weeks after start of chemotherapy is a robust predictor of survival in patients with inoperable cholangiocarcinoma in four independent data sets.