The patient was diagnosed with lung adenocarcinoma...biopsy tissue sample revealed a CD74–ROS1 gene fusion...patient started the first-line therapy with ceritinib (450 mg orally once a day). Two months later, he achieved a partial response...However, the disease progressed at the end of July as PET-CT revealed multiple lymph nodes metastases and bone destruction...A second NGS assay found a possible resistance mutation of c.6012T>G (p.F2004L) (MAF 1.65%) in ROS1 kinase domain in the plasma circulating tumor DNA in addition to the ROS1 fusion.