NRAS and neoplasm: With a cut-off of 10 % allele frequency for variant calling, the most frequently mutated genes, respective sequence variants occurring in at least 2 tissue specimens of primary tumour and/or liver and/or lung metastases were: TP53 (10/14 cases), APC (8/14 cases), KRAS (8/14 cases), SMAD4 (2/14 cases) as well as FGFR3 (1/14 cases) and PIK3CA (1/14 cases) and NRAS (1/14 cases) (Table 2).