European Journal of Epidemiology

, Volume 22, Issue 9, pp 577–588 | Cite as

Timing of blood extraction in epidemiologic and proteomic studies: results and proposals from the PANKRAS II Study

  • Miquel Porta
  • José Pumarega
  • Olga Ferrer-Armengou
  • Tomàs López
  • Joan Alguacil
  • Núria Malats
  • Esteve Fernàndez
  • for the PANKRAS II Study Group


There are no consensus guidelines or standards for epidemiologic and ‘-omics’ studies using blood biomarkers on how to report the timing of extraction of blood samples. However, disease-induced changes in blood concentrations of exogenous and endogenous compounds may bias studies. The aim of the present report is to describe the timing of blood collection with respect to a variety of relevant clinical events in the PANKRAS II Study, and to suggest ways to display graphically the quantitative information. Subjects were 167 incident cases of exocrine pancreatic cancer prospectively recruited in five teaching hospitals in eastern Spain. Over 80% of patients had blood extracted during the first 6 months since onset of cancer symptoms, and 82% within the first month of admission to a study hospital. Over 80% of cases had blood drawn after an ultrasound, a CT scan or an ERCP, 25% after a laparotomy, and 37% after treatment onset. All three intervals from blood extraction to diagnosis, to treatment onset and to interview had a median of 0 days, and 88% of cases had blood drawn within 2 weeks of diagnosis. Over 72% of cases had concentrations of total lipids in the medium, normal range. Results suggest ways to report intervals involving blood biomarkers and may contribute to develop consensus guidelines and standards on the collection of blood samples in epidemiologic and ‘-omics’ research.


Pancreatic neoplasms Blood extraction Lipids/blood Epidemiology Molecular Research design/organization and administration Proteomics Genomics “-omics” research Epidemiology/methods Epidemiology/standards 



Multicentre prospective study on the role of K-ras and other genetic alterations in the diagnosis, prognosis and etiology of pancreatic and biliary diseases


Exocrine pancreatic cancer


Confidence interval


Standard deviation


Computerized axial tomography


Endoscopic retrograde colangiopancreatography


Transparietohepatic cholangiography


Tumour-node-metastasis system


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Miquel Porta
    • 1
    • 2
    • 3
  • José Pumarega
    • 1
    • 3
  • Olga Ferrer-Armengou
    • 1
  • Tomàs López
    • 1
    • 3
  • Joan Alguacil
    • 1
    • 3
    • 4
  • Núria Malats
    • 1
  • Esteve Fernàndez
    • 5
  • for the PANKRAS II Study Group
  1. 1.Clinical & Molecular Epidemiology of Cancer Unit, Institut Municipal d’Investigació MèdicaUniversitat Autònoma de BarcelonaBarcelonaSpain
  2. 2.School of MedicineUniversitat Autònoma de BarcelonaBarcelonaSpain
  3. 3.CIBER en Epidemiología y Salud Pública (CIBERESP)BarcelonaSpain
  4. 4.Department of Environmental Biology & Public HealthUniversity of HuelvaHuelvaSpain
  5. 5.Institut Català d’OncologiaBarcelonaSpain

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