Fig. 2. Flowchart representing the process from collecting tissue samples to NGS results.

Upper row represents the newly obtained tissue samples collected through new biopsies. The bottom row represents the archived tissue samples formerly obtained during the disease. Tumour tissue contains all the samples received for assessment. Formalin-fixed paraffin-embedded (FFPE) specimen insufficient includes those samples in which tumour tissue is not present at macroscopic evaluation. At the pathological assessment, material was judged microscopically by a specialised pathologist. No tumour present contains all samples without (previous) evidence of containing vital tumour cells. Next DNA was isolated, before next-generation sequencing was performed. The last numbers represent the tissue samples with a minimal tumour content of 30% as required and were considered valid.