This bill aims to expand Medicare coverage to include lung cancer biomarker testing for individuals diagnosed with the disease. It specifically amends the Social Security Act to add this testing as a covered service under Medicare Part B. The legislation defines "lung cancer biomarker testing" as a test performed on or after January 1, 2027, to identify specific biomarkers such as genes, proteins, or other molecules from a patient's tissue, blood, or bodily fluids. This testing is crucial for guiding personalized treatment decisions for lung cancer patients. A significant provision of the bill is the requirement for Medicare to pay 100 percent of the reasonable charges for these lung cancer biomarker tests. This ensures that beneficiaries will not face out-of-pocket costs for this essential diagnostic service.