Figure 1.

Design of the study. The full cohort comprised 38 cancer specimens that were collected and sampled in parallel to allow standard fixation (i.e., at room temperature) and cold formalin fixation (i.e., at 4°C). Following processing and tissue sectioning the H&E slides were reviewed to identify the tumor area that was mesodissected for DNA extraction. Two independent cohorts were prospectively collected: Cohort A, whose sampled were collected 6 years prior to the study and DNA extraction performed at present time; Cohort B, whose samples were collected at time of the present study with contextual DNA extraction. For 14 samples from Cohort B, i.e., corresponding to those samples for which at least 6 months elapsed from collection, two DNA extractions were performed: at baseline (at time of collection/fixation) and after 6 months of storage/archival. On the total 90 DNA samples we performed fluorometric and spectrophotometric quantifications and we ran a qPCR with the DEPArray™ FFPE QC Kit. RT, room temperature; NBF, neutral buffered formalin; EtOH, ethanol.