Bridging Targeting Precision and Oncologic Safety: Localization Accuracy for Margin Adequacy in Cone-Beam Computed...

Area of Science:

• Thoracic surgery
• Medical imaging
• Oncology

Background:

• Ground-glass pulmonary nodules require precise localization for adequate resection margins.
• Current methods lack a validated threshold for localization accuracy in thoracoscopic surgery.
• Image-guided localization aims to improve pathological margin adequacy.

Purpose of the Study:

• To evaluate the association between the distance to the nodule margin (Dmn) and pathological margin adequacy.
• To identify a clinically relevant threshold for localization accuracy in image-guided pulmonary nodule resection.

Main Methods:

• Retrospective review of 169 patients undergoing cone-beam CT-guided localization (hook-wire or dye) followed by thoracoscopic wedge resection.
• Dmn defined as the shortest 3D Euclidean distance from needle tip to tumor margin.
• Pathological margin adequacy defined as resection margin ≥ maximum tumor diameter.

Main Results:

• Dmn was independently associated with pathological margin inadequacy (OR 1.617, p < 0.001).
• An optimal Dmn cutoff of 4.9 mm was identified (AUC 0.827), with 71.0% sensitivity and 94.2% specificity.
• Margin inadequacy was significantly higher for Dmn ≥ 4.9 mm (73.3%) compared to Dmn < 4.9 mm (6.5%, p < 0.001).

Conclusions:

• A Dmn of approximately 4.9 mm is associated with pathological margin inadequacy in cone-beam CT-guided pulmonary nodule localization.
• This Dmn value may serve as a candidate intraoperative warning threshold for margin reassessment.
• Prospective external validation is necessary before routine clinical implementation.