AUTHOR=Xu Long , Chen Xiaoxia , Huo Hong , Liu Yongye , Yang Xiaodan , Gu Dejian , Yuan Mingming , Zhang Min , Chen Rongrong , Wang Jiayin , Zheng Zhendong 

TITLE=Case Report: Detection of Double ROS1 Translocations, SDC4-ROS1 and ROS1-GK, in a Lung Adenocarcinoma Patient and Response to Crizotinib

JOURNAL=Frontiers in Medicine

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.649177

DOI=10.3389/fmed.2021.649177

ISSN=2296-858X

ABSTRACT=<p><italic>ROS1</italic> rearrangement, identified in ~2% of non-small cell lung cancer (NSCLC), has defined a distinctive molecular subtype. Patients with <italic>ROS1</italic> fusion have been shown to be highly sensitive to treatment with crizotinib. However, the efficacy of crizotinib in NSCLC patients with double <italic>ROS1</italic> fusions remains to be elucidated. Here, we report a 40-year-old male diagnosed with stage IIIA lung adenocarcinoma. Two <italic>ROS1</italic> fusions [SDC4-<italic>ROS1</italic> (EX2:EX32) and <italic>ROS1</italic>-GK (EX31:EX13)] were detected simultaneously in tumor tissue of this patient by next-generation sequencing. Crizotinib was administered, and the patient showed a partial response in lung lesions. Nevertheless, a brain lesion was found at 8 months after treatment. The slightly short duration of response may be related to the presence of <italic>ROS1-GK</italic> rearrangement. This case proved that patients with <italic>SDC4-ROS1</italic> and <italic>ROS1-GK</italic> fusions may be sensitive to crizotinib, but short progression-free survival of this case showed that the presence of ROS1-GK rearrangement may affect the efficacy of crizotinib. A large-scale investigation on the efficacy of <italic>ROS1</italic> inhibitors in patients with complex <italic>ROS1</italic> fusions should be conducted in the future.</p>