Pulmonary segmental resection (segmentectomy) is a challenging operation due to the difficulty in identifying intersegmental planes within a single pulmonary lobe. We evaluated the safety, feasibility and added value of a novel operative technique that utilizes near-infrared fluorescence (NIF) with indocyanine green (ICG) dye to clearly delineate intersegmental planes and facilitate pulmonary segmentectomy.

Patients aged >18 years presenting with T1aN0 NSCLC confined to one bronchopulmonary segment were eligible to participate in this prospective Phase I study. The tumor-containing target segment was first isolated from blood supply by division of the segmental vein, artery and bronchus. Then the “predicted” intersegmental plane was marked with cautery. An ICG bolus of 25mg was injected systemically, allowing the entire lung to fluoresce, except for the target segment which remained dark. The “true” intersegmental plane was then identified as the line between the fluorescent and dark parenchyma. The operation was concluded if the excised segment contained the tumor with clear margins; otherwise, the patient received a completion lobectomy. The procedure was successful if the patient scored 7/7 on a pre-defined evaluation scale. The distance between the “true” versus “predicted” intersegmental plane was measured to determine the added margin length achievable by NIF. Descriptive statistics were generated.

Twenty patients have been enrolled in this study to date (Target: n=30). Median tumor size was 2.3 cm (SD 1.22 cm). Eight patients (8/20, 40%) proceeded directly to lobectomy. Twelve patients (12/20, 60%) underwent NIF-guided procedure, with 11/12 (92%) successfully completing a segmentectomy, and 1/12 (8%) proceeding to completion lobectomy for positive margins. The median added margin length was +2.1 cm (SD 1.6 cm). Median hospital stay was 3.6 days (SD 1.6). There were no mortalities or complications greater than Grade II.

NIF can enhance the visualization of intersegmental planes, allowing for easier segmentectomy with added margin length.

Feasibility, Safety, and Added Margin Length of Near-Infrared Fluorescence Guided Robotic Pulmonary Segmentectomy for Early Stage Lung Cancer: A Phase I Study