Activating MAPK pathway mutations including KRAS c.35G>A (p.G12D; COSM521) and GNAS c.601C>T (p.R201C; COSM27887) were identified in two tumor samples (2/15, 13%), with these mutations co-occurring in both tumors (NECC015, NECC012). The gene discussed is GNAS; the disease is neoplasm.