title: Sequential Validation of Blood-Based Protein Biomarker Candidates for Early-Stage Pancreatic Cancer.
abstract: CA19-9, which is currently in clinical use as a pancreatic ductal adenocarcinoma (PDAC) biomarker, has limited performance in detecting early-stage disease. We and others have identified protein biomarker candidates that have the potential to complement CA19-9. We have carried out sequential validations starting with 17 protein biomarker candidates to determine which markers and marker combination would improve detection of early-stage disease compared with CA19-9 alone.
  
  
  
  Candidate biomarkers were subjected to enzyme-linked immunosorbent assay based sequential validation using independent multiple sample cohorts consisting of PDAC cases (n = 187), benign pancreatic disease (n = 93), and healthy controls (n = 169). A biomarker panel for early-stage PDAC was developed based on a logistic regression model. All statistical tests for the results presented below were one-sided.
  
  
  
  Six out of the 17 biomarker candidates and CA19-9 were validated in a sample set consisting of 75 PDAC patients, 27 healthy subjects, and 19 chronic pancreatitis patients. A second independent set of 73 early-stage PDAC patients, 60 healthy subjects, and 74 benign pancreatic disease patients (combined validation set) yielded a model that consisted of TIMP1, LRG1, and CA19-9. Additional blinded testing of the model was done using an independent set of plasma samples from 39 resectable PDAC patients and 82 matched healthy subjects (test set). The model yielded areas under the curve (AUCs) of 0.949 (95% confidence interval [CI] = 0.917 to 0.981) and 0.887 (95% CI = 0.817 to 0.957) with sensitivities of 0.849 and 0.667 at 95% specificity in discriminating early-stage PDAC vs healthy subjects in the combined validation and test sets, respectively. The performance of the biomarker panel was statistically significantly improved compared with CA19-9 alone (P < .001, combined validation set; P = .008, test set).
  
  
  
  The addition of TIMP1 and LRG1 immunoassays to CA19-9 statistically significantly improves the detection of early-stage PDAC.
authors.affiliation: Departments of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Michela
authors.initials: M
authors.lastname: Capello
authors.affiliation: Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Leonidas E
authors.initials: LE
authors.lastname: Bantis
authors.affiliation: International Agency for Research on Cancer (IARC) Lyon, France.
authors.forename: Ghislaine
authors.initials: G
authors.lastname: Scelo
authors.affiliation: Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: International Agency for Research on Cancer (IARC) Lyon, France.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: Departments of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Dilsher S
authors.initials: DS
authors.lastname: Dhillon
authors.affiliation: Departments of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Nikul J
authors.initials: NJ
authors.lastname: Patel
authors.affiliation: Departments of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Deepali L
authors.initials: DL
authors.lastname: Kundnani
authors.affiliation: Departments of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.affiliation: Division of Medical Oncology, Duke University, Durham, NC, USA.
authors.forename: James L
authors.initials: JL
authors.lastname: Abbruzzese
authors.affiliation: Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Anirban
authors.initials: A
authors.lastname: Maitra
authors.affiliation: Pancreas Center, University of California San Francisco, Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Tempero
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: Randall
authors.initials: R
authors.lastname: Brand
authors.affiliation: Department of Surgery, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Firpo
authors.affiliation: Department of Surgery, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Sean J
authors.initials: SJ
authors.lastname: Mulvihill
authors.affiliation: Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Katz
authors.affiliation: International Agency for Research on Cancer (IARC) Lyon, France.
authors.forename: Paul
authors.initials: P
authors.lastname: Brennan
authors.affiliation: Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Ziding
authors.initials: Z
authors.lastname: Feng
authors.affiliation: Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Ayumu
authors.initials: A
authors.lastname: Taguchi
authors.affiliation: Departments of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Samir M
authors.initials: SM
authors.lastname: Hanash
mesh_terms: D000368:Aged; D000951:Antigens, Neoplasm / Q000097:blood; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D021441:Carcinoma, Pancreatic Ductal / Q000097:blood* / Q000473:pathology; D016022:Case-Control Studies; D024102:Collagen Type VIII / Q000097:blood; D043170:Collagen Type XVIII; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D037181:Lectins, C-Type / Q000097:blood; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000473:pathology; D050500:Pancreatitis, Chronic / Q000097:blood; D000073718:Pancreatitis-Associated Proteins; D012372:ROC Curve; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000097:blood; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000097:blood*
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; C000612902:COL18A1 protein, human; D024102:Collagen Type VIII; D043170:Collagen Type XVIII; D006023:Glycoproteins; C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; C015246:LRG1 protein, human; D037181:Lectins, C-Type; D000073718:Pancreatitis-Associated Proteins; C000612141:REG3A protein, human; D047888:Receptors, Tumor Necrosis Factor, Type I; C560822:TIMP1 protein, human; C506235:TNFRSF1A protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1