Furmonertinib Combined With Intrathecal Chemotherapy and Stereotactic Radiotherapy (SRT) for EGFR-Mutated NSCLC Patients With Brain Parenchymal and Leptomeningeal Metastases

This study tests a combination treatment for people with advanced lung cancer that has spread to the brain — specifically combining a targeted drug (furmonertinib), chemotherapy injected directly into the fluid around the spine (intrathecal chemotherapy), and focused radiation (stereotactic radiotherapy). **You may be eligible if...** - You are between 18 and 75 years old - You have been diagnosed with lung adenocarcinoma (a type of non-small cell lung cancer) that is advanced or metastatic - Your tumor has a specific genetic mutation called EGFR (either 19Del or L858R) - Your cancer has spread to both the brain tissue and the lining around the brain (leptomeningeal metastases) - You have not received prior systemic cancer treatment **You may NOT be eligible if...** - You do not have the specific EGFR mutation - You have already received systemic anti-cancer treatment - You have poor overall health or organ function Talk to your doctor to see if this trial is right for you.