Skip to main content
. 2017 Jul 7;8(49):85234–85251. doi: 10.18632/oncotarget.19076

Figure 8. Droplet digital PCR accurately assesses MYCN and ALK copy numbers from neuroblastoma patient plasma and the corresponding primary tumor biopsy.

Figure 8

MYCN (A) and ALK (B) copy numbers were determined by ddPCR from retrospectively collected biomaterial samples from 10 neuroblastoma patients. Black bars show numbers determined from genomic DNA isolated from the tumor biopsy (single measurements). Red bars show values determined from cell-free DNA in the corresponding 200 µl plasma sample (single measurements). MYCN and ALK status determined at diagnosis (shown below bar graphs in A and B) were provided from patient records and were determined by FISH or qPCR (indicated) analysis. Dashed lines indicate the thresholds used for FISH analysis of the neuroblastoma biopsy in the German NB2004 trial protocol: diploid MYCN (2 copies), MYCN gain (≥ 3 copies) and MYCN amplification (> 8 copies). Correlation analysis of copy numbers determined from plasma-derived cell-free DNA (y-axis) and tumor biopsy genomic DNA (x-axis) is shown for MYCN (C) and ALK (D). Spearman correlation coefficients (r) and p-values are indicated.