Abstract
In recent years, perioperative immune checkpoint inhibitors have become indicated for early-stage lung cancer, emphasizing the importance of high-resolution endoscopic evaluation of preoperative drug therapy. At the initial evaluation, a male patient in his 60s presented with a primary lesion obstructing the right upper lobe bronchus. After three courses of neoadjuvant immunochemotherapy, chest computed tomography and endoscopic examinations showed a near-complete response. Narrow-band imaging indicated that subepithelial vascular regularity and distribution patterns were within normal limits. However, autofluorescence imaging (AFI) revealed a magenta-colored area on the bronchial epithelium corresponding to the initial lesion site. Two months later, the magenta coloration faded, suggesting pathological normalization of the bronchial epithelium thickening. AFI enabled visualization of tumor progression in the bronchi otherwise completely obstructed by the lesion, potentially offering valuable information to determine bronchial resection lines during surgery.