KRAS and Patent ductus arteriosus: However, a retrospective analysis of 117 patients with archival tumors available for KRAS mutation testing noted superior OS with erlotinib in KRAS wild-type (KRASWT) vs. KRAS-mutated (KRASMUT) PDA (6.1 vs. 4.5 months, HR = 0.66, p = 0.34) [10].