D110-11 Navigated Superselective Intrabronchial Brachytherapy as a Curative Treatment for Peripheral Lung Cancer in Special Groups

Introduction Radiotherapy is widely utilized in the management of lung cancer. However, conventional external beam radiotherapy often damages normal lung tissue, the chest wall, and mediastinal organs. We report a case of an elderly patient with locally recurrent pulmonary squamous cell carcinoma treated with navigated superselective intrabronchial brachytherapy (NSIB) four years after initial surgery. Case Report An 80-year-old male underwent radical surgical resection ten years ago for squamous cell carcinoma of the left upper lobe (T2aN1M0, Stage IIA). Due to advanced age and frail condition, he received no adjuvant therapy and was maintained on routine CT surveillance. Four years post-operatively, a new nodule was identified in the left lower lobe. After antibiotic therapy demonstrated no effect, the nodule showed significant enlargement on subsequent imaging one year later. Pathological diagnosis was confirmed via electromagnetic navigational bronchoscopy with endobronchial ultrasound-guided transbronchial lung biopsy. PET/CT revealed no distant metastasis, confirming local recurrence.Given the patient’s comorbidities, prior thoracic surgery, and refusal of conventional treatments including surgery, EBRT, or systemic therapy, NSIB was selected as the definitive treatment modality. The patient subsequently underwent three sessions of NSIB within one week.Follow-up chest CT one month post-treatment showed reduction in nodule diameter from 12.2 mm to 9.6 mm. Subsequent imaging demonstrated sustained stability in lesion size. At the 5-year follow-up, the nodule measured 9.8 mm with repeated PET/CT scans confirming absence of metabolic activity. Discussion This case demonstrates successful integration of navigational bronchoscopy with intrabronchial brachytherapy for lung cancer treatment. The patient tolerated the procedures well, and long-term follow-up showed maintained local control with no metabolic activity, suggesting curative treatment outcome.Compared to conventional radiotherapy, NSIB enables precise applicator placement through the tumor center, delivering high radiation doses to the tumor while maintaining rapid dose fall-off to surrounding tissues. This characteristic minimizes radiation exposure to normal structures and eliminates respiratory motion concerns. Unlike percutaneous approaches, NSIB offers inherent advantages including minimal invasiveness, procedural reproducibility, and reduced complication risks such as pneumothorax.NSIB achieved durable local control in this high-risk patient, providing a valuable treatment alternative for medically inoperable lung cancer cases. This approach represents a promising therapeutic strategy for selected patients who are not candidates for conventional treatment modalities.