NRAS mutations (G12D/R, G13R, Q61K/R/L) were detected in 13 of 71 (18%) progressive tumors and KRAS mutations (G12C, G12R, Q61H) in 5 of 71 (7%) progressive tumors (Supplementary Fig. S3). Mutant BRAF amplification (2-15 fold or 4-75 copies) was detected in 11 of 57 (19%) progressive tumors, mutant BRAF alternative splice variants were detected in 6 of 48 (13%) progressive tumors. MEK1 activating mutations (K57N (22), C121S) were detected in 2 of 71 (3%) progressive tumors, recurrent CDKN2A loss in 3 of 44 or 7% of progressive tumors. AKT1/3 mutations (Q79K, E17K) were discovered in 2 of 44 progressive tumors. Mutations in PIK3CA, PIK3CG and in PIK3R2, PTEN, PHLPP1 were detected in 10 of 44 progressive tumors.