EGFR and adenocarcinoma: 8 studies tested targeted therapies in molecularly enriched populations in accordance with EGFR status (immunocytochemistry positive [16]; wild-type [24, 31, 32]), KRAS status (wild-type) [25], expression of MET (immunocytochemistry 2+/3+) [29] and histological type (non-adenocarcinoma [21]; non-squamous cell carcinoma [22, 24, 32]).