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Page 4 of 10 Finzel et al. J Cancer Metastasis Treat 2018;4:21 I http://dx.doi.org/10.20517/2394-4722.2018.10

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Figure 1. Patient and variant categories. (A) Patient categories. Fully shared: patient having all the variants (1&2) detected in both the
solid and liquid biopsies; partially shared: patient having different variants detected in the solid and/or liquid biopsies (4&5), and some
variants that are shared (3); only in solid: patient having variants (6&7) only detected in the solid biopsy; only in liquid: patient having
variants (8&9) detected only in the liquid biopsy; (B) Variant categories. Shared: variants that are detected in both the solid and liquid
biopsy. These variants can be from “fully shared” patients or common variants from “partially shared” patients; solid: variants that are
detected only in the solid biopsy. These can be from “only solid” patients or variants present only in tissue biopsy in “partially shared”
patients; liquid: variants that are detected only in the liquid biopsy. These can be from “only liquid” patients or variants present only in
blood in “partially shared” patients

Clinical value of the detected aberrations
To evaluate the impact of the variants on the function of the proteins and on clinical benefit, a literature
search was performed to identify in vitro studies, Food and Drug Administration (FDA) labels, guidelines
and published retrospective and prospective clinical studies pertaining to genomic alterations in each gene
and their association with functional impact on the protein and outcomes in cancer patients. Based on this
research, variants were classified into four categories.

For the purposes of this study, the data shown refer only to the 27 genes of the panel comprising the liquid
biopsy part of OncoSTRAT&GO™ [Supplementary Table 3], which are also included in the solid biopsy panel.

RESULTS
We analysed data from 351 patients who were molecularly characterized from May 2016 to November 2017
using the OncoSTRAT&GO™ profiling solution, which combines the analysis by NGS of genetic variants in
the solid and liquid (blood) biopsies.

Different genetic information revealed in the solid vs. the liquid biopsy
Patients with no variant detected in the tissue or the blood biopsy represented 11% of the total population
and were excluded from further analysis. We classified the remaining patients (n = 313) into four categories
according to the mutation discrepancies found between their solid and liquid biopsies [Figure 1A]. This
analysis showed that 41% of the patients carried mutations that were detected only in the solid biopsy, while
for 4% of the cases, variants were found only in the blood. On the other hand, 41% of samples had partially
shared mutations, and only 14% of the samples fully shared the gene variants in both biopsies [Figure 2].
These results suggest that in 86% of the patients, solid and liquid biopsies provide different information
regarding genetic alterations.

Since the category “partially shared” includes patients who share variants in the two biopsies, we further
performed a classification at the variant level by grouping the mutations in three categories: shared, solid
and liquid [Figure 1B]. This analysis indicated that in the majority of the cases (60%), tissue and blood
biopsies analysis showed discrepant patterns: 51% of the variants were detected only in the solid biopsy, while