ERBB4 and gastric adenocarcinoma: We detected hotspot mutations in ERBB3 (V104M/L and S846I) and ERBB4 (L798R/P), albeit with lower frequency than in ERBB2. These hotspots have been previously reported in e.g. gastric adenocarcinomas (GA) and CRC but, to our knowledge, not in SBA [46].