**2. Harmonization of sample collection and derivative preservation**

To guarantee the integrity of biomarkers to be tested and to avoid bias, pre-analytical variables must be carefully considered [6]. In fact, many studies are being conducted to elucidate the effects of pre-analytical variables on analytical profiles. In this sense, a study has been recently published to determine acceptable delays to fixation for formalin-fixed paraffin-embedded (FFPE) tissue samples [7]. In order to mitigate their impact in the complex frame of multicenter projects, biobanks contribute through supervised materials and sample handling and continuous and overlapped checkpoints.
