PIK3CA mutations and PTEN loss are negatively associated with survival in mCRCs patients treated with panitumumab or cetuximab...PTEN loss was similarly associated with shorter PFS (P = 0.0681) that reached statistical significance if this variable was combined with PIK3CA mutations (loss of PTEN and/or PIK3CA mutation; P = 0.0066; Fig. 1D–E)...PTEN loss of expression was significantly associated with worse OS (P = 0.0048), as was the combination of PTEN loss with PIK3CA mutations (P = 0.0161; Fig. 2D–E).