This is an an interventional study to explore the mechanism of cerebrospinal fluid immune microenvironment in patients with advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer with brain metastases treated with Iruplinalib.

Inclusion Criteria:

• Histologically or cytologically confirmed diagnosis of advanced non-small cell lung cancer(NSCLC) that is anaplastic lymphoma kinase (ALK)-postive as assessed by the next-generation sequencing (NGS) test.
• Confirmed diagnosis of brain metastases or suspected brain metastases
• Iruplinalib is proposed for treatment
• Eastern Cooperative Oncology Group(ECOG) Performance Status of 0-1
• Adequate organ and marrow function

Exclusion Criteria:

• Have serious gastrointestinal disease or other uncontrolled internal diseases and infections
• The presence of mental illness or substance abuse at the time of screening that may have affected compliance with the trial
• The presence of pleural fluid or ascites that requires treatment or is judged by the investigator to be uncontrollable at the time of screening
• Arterial/venous thrombosis events occurred within 6 months prior to administration, such as cerebrovascular accidents, deep vein thrombosis, and pulmonary embolism