Plasma Molecular Profiling in ALK Inhibitor Resistant NSCLC

Inclusion Criteria: * Patients with advanced ALK fusion oncogene positive lung adenocarcinoma that have progressed after 1-2 ALK inhibitors, with at least one prior line of 2nd generation ALKi (i.e. Ceritinib, Alectinib, Brigatinib or Ensartinib) * The availability of sufficient plasma * Age ≥ 21 years * WHO performance status ≤ 2 * Life expectancy of ≥ 21 weeks * Patients should have adequate organ function for potential consideration into clinical trials (routine blood tests are valid within 14 days before enrollment): 1. Adequate bone marrow function as shown by: ANC ≥ 1.0x10\^9/L, Platelets ≥ 75x10\^9/L, Hb ≥ 7.5 g/dL 2. Alanine aminotransferase (ALT) and aspirate aminotransferase (AST) normal range (or ≤ 3.0xULN if liver metastases are present) * Willing to provide signed informed consent * Patients whom do not fulfill the above criteria may be discussed on a case-by-case basis within the study team, for potential enrolment Exclusion Criteria: * Received more than 2 prior ALK inhibitors (ALKi) * Symptomatic or uncontrolled brain metastases requiring concurrent treatment inclusive but not limited to surgery and radiation. Stable/ tailing doses of corticosteroids is permitted