The VENTANA ROS1 (SP384) Rabbit Monoclonal Primary Antibody, the first and only in vitro diagnostic ROS1 immunohistochemistry (IHC) assay detects the presence of ROS1 protein in tissue, and may be useful in identifying ROS1-positive cancer cases. Guidelines from the College of American Pathologists and the National Comprehensive Cancer Network recommend ROS1 testing for confirmed lung adenocarcinoma cases.