 Analysis of the cell pellet will be carried out applying the sensitive massively parallel sequencing method published by Kinde et al. 2. Mutations in the following genes will be analysed: AKT1, APC, BRAF, CTNNB1, EGFR, FBXW7, KRAS, NRAS, PTEN, PIK3CA, PPP2R1A, and TP53. 