Supplementary Material for: Successful EGFR Mutation Detection in Cytological Specimens of Lung Cancer with Challenging Biopsies by Integrating Virtual Bronchoscopy Navigation and Endobronchial Ultrasound Guidance with Highly Sensitive Next-Generation Sequencing: A Case Report

Introduction: This case report presents the successful detection of an EGFR exon 19 deletion using virtual bronchoscopic navigation (VBN) and endobronchial ultrasound with guide sheath (EBUS-GS) brushing, integrated with highly sensitive next-generation sequencing (NGS), even in challenging biopsy scenarios. The growing prevalence of driver gene alterations in non-small cell lung cancer necessitates effective bronchoscopic technology and reliable multiplex gene NGS panels. However, data regarding the optimal bronchoscopic techniques when using highly sensitive NGS panels are limited. Herein, we report a case utilizing VBN-guided EBUS-GS brushing as an exploratory approach to address this challenge.
Case presentation: A 71-year-old man was evaluated for a band-like lesion near the left pleura during spinal cord infarction. Transbronchial specimens were obtained from lesions invisible on conventional chest radiography and X-ray fluoroscopy using VBN and EBUS-GS brushing. Cytological brushing specimens revealed lung adenocarcinoma, and highly sensitive NGS identified an EGFR exon 19 deletion. He was diagnosed with stage IB disease and underwent radical radiotherapy owing to his fragile condition. If recurrence occurs, the patient will be treated with an EGFR inhibitor.
Conclusion: VBN-guided EBUS-GS brushing, a minimally invasive approach, combined with highly sensitive NGS has the potential to provide accurate molecular diagnoses to more patients with lung cancer, thereby offering opportunities for personalized treatment. Our findings warrant further investigation to determine optimal bronchoscopic technologies for obtaining tumor specimens.