ERBB3 and adenocarcinoma: In 38 cases of adenocarcinoma, excluding three cases of rare subtypes, the median OS was 21.0 months (95% CI: 15.6–32.2) in the HER3 (2+/3+) group and 17.1 months (95% CI: 8.9–27.8) in the HER3 (0/1 +) group.