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

Background/Objectives: Ground-glass pulmonary nodules are often nonpalpable and not visible during thoracoscopic surgery, making accurate localization important for achieving adequate pathological margins. However, no clinically validated localization-error threshold has been established. We evaluated the association between Dmn and pathological margin adequacy after image-guided thoracoscopic pulmonary nodule resection and sought to identify a clinically relevant localization-accuracy threshold. Methods: We retrospectively reviewed 169 patients in a predefined peripheral-lesion cohort who underwent cone-beam computed tomography-guided pulmonary nodule localization using hook-wire placement or dye marking in a hybrid operating room, followed by thoracoscopic wedge resection. Dmn was defined as the shortest three-dimensional Euclidean distance from the localization needle tip to the tumor margin. Pathological margin adequacy was defined as a resection margin equal to or greater than the maximum tumor diameter. Logistic regression was used to identify predictors of pathological margin inadequacy, and receiver operating characteristic analysis was performed to determine the optimal Dmn cutoff. Results: Dmn was independently associated with pathological margin inadequacy (odds ratio, 1.617; 95% confidence interval, 1.356-1.928; p < 0.001). Receiver operating characteristic analysis yielded an area under the curve of 0.827 and an optimal Dmn cutoff of 4.90 mm, with a sensitivity of 71.0% and specificity of 94.2%. Pathological margin inadequacy occurred more frequently in patients with Dmn ≥ 4.9 mm than in those with Dmn < 4.9 mm (73.3% vs. 6.5%, p < 0.001). Conclusions: In this single-center cohort, a Dmn of approximately 4.9 mm was associated with pathological margin inadequacy after cone-beam computed tomography-guided pulmonary nodule localization and thoracoscopic wedge resection. This value may serve as a candidate intraoperative warning threshold for margin reassessment; however, prospective external validation is required before routine clinical implementation.