Phase II Study to Evaluate the Impact of SBRT (Stereotactic Body Radiation Therapy) and/or SRS (Stereotactic Radiosurgery) on Oligoresidual Disease in EGFR Mutation Patients Treated with Osimertinib as First-Line Systemic Intervention. All candidates must exhibit a partial response after 12 weeks of treatment with the third-generation tyrosine kinase inhibitor (alone or in combination with chemotherapy) and a maximum of five (5) residual lesions in a maximum of two (2) organs. The primary outcome will be progression-free survival (PFS), and secondary outcomes will include overall survival (OS), proportion of patients without progression at months 12 and 36, safety, and overall response rate (ORR). Additionally, an exploratory analysis will be conducted on the prognostic value of liquid biopsy (supplementary information), considering baseline presence of mutations (determined by Next Generation Sequencing tests) and reduction or negativization of allelic fraction (AF).
Be older than 18 years of age.
Be capable of giving informed consent to participate in the study.
Have histological confirmation compatible with EGFR mutant non-small cell lung cancer (NSCLC) and metastatic disease (with or without histological confirmation of metastatic lesions).
Have confirmation of the presence of common EGFR mutations (exon 19 deletion, L858R/exon 21, or G719X) through any locally and internationally accepted standard tests.
Severe comorbidities contraindicating radiation therapy.
Bone metastases in the femur with a high risk of fracture.
Complete response to Osimertinib treatment (no oligoresidual disease for ablative treatment).
Inability to treat all oligoresidual lesions with ablative intent.