ALK and squamous cell carcinoma: ALK rearrangements were observed in 6.92% (55 articles: 918/13275), 0.92% (26 articles: 16/1746), 11.54% (13 articles: 9/78) and 5.97% (13 articles: 4/67) patients with lung adenocarcinomas, squamous carcinomas, adenosquamous carcinomas and large cell carcinomas, respectively (Table S3).