Serum CA19-9 response as a surrogate for clinical outcome in patients receiving fixed-dose rate gemcitabine for advanced pancreatic cancer.

Journal Article

The use of serial serum measurements of the carbohydrate antigen 19-9 (CA19-9) to guide treatment decisions and serve as a surrogate end point in clinical trial design requires further validation. We investigated whether CA19-9 decline represents an accurate surrogate for survival and time to treatment failure (TTF) in a cohort of 76 patients with advanced pancreatic cancer receiving fixed-dose rate gemcitabine in three separate studies. Statistically significant correlations between percentage CA19-9 decline and both overall survival and TTF were found, with median survival ranging from 12.0 months for patients with the greatest degree of biomarker decline (> 75%) compared with 4.3 months in those whose CA19-9 did not decline during therapy (P < 0.001). Using specific thresholds, patients with > or = 25% decline in CA19-9 during treatment had significantly better outcomes than those who did not (median survival and TTF of 9.6 and 4.6 months vs 4.4 and 1.5 months; P < 0.001). Similar results were seen using both 50 and 75% as cutoff points. We conclude that serial CA19-9 measurements correlate well with clinical outcomes in this patient population, and that decline in this biomarker should be entertained for possible use as a surrogate end point in clinical trials for the selection of new treatments in this disease.

Full Text

Duke Authors

Cited Authors

  • Ko, AH; Hwang, J; Venook, AP; Abbruzzese, JL; Bergsland, EK; Tempero, MA

Published Date

  • July 2005

Published In

Volume / Issue

  • 93 / 2

Start / End Page

  • 195 - 199

PubMed ID

  • 15999098

Electronic International Standard Serial Number (EISSN)

  • 1532-1827

International Standard Serial Number (ISSN)

  • 0007-0920

Digital Object Identifier (DOI)

  • 10.1038/sj.bjc.6602687

Language

  • eng