Impact of CT-guided hookwire localization on tumor spread through air spaces in stage IA lung adenocarcinoma

Background: It remains undetermined whether preoperative computed tomography (CT)-guided hookwire localization would result in elevated risk of tumor spread through air spaces (STAS) in stage IA lung adenocarcinoma.Methods: A total of 1836 patients who underwent lobectomy were included. To eliminate the potential impact of confounding factors on producing STAS, propensity score-matching (PSM) was used to create two balanced subgroups stratified by implementation of hookwire localization. We also introduced an external cohort including 1486 patients to explore the effect of hookwire localization on the incidence of STAS and patient survival after sublobar resection (SR). For proactive simulation of hookwire localization, 20 consecutive lobectomy specimens of p-stage IA lung adenocarcinoma were selected.Results: Ex vivo tests revealed that mechanical artifacts presenting as spreading through a localizer surface (STALS) could be induced by hookwire localization but be distinguished by CD68 and AE1/3 antibody-based immunohistochemistry. The distance of STALS dissemination tended to be shorter compared with real STAS (P = 0.000). After PSM, implementation of hookwire localization was not associated with elevated STAS incidence, nor worse survival in p stage IA patients undergoing lobectomy irrespective of STAS. Conclusions: CT-guided hookwire localization might induce mechanical artifacts presenting as STALS which could be distinguished by immunohistochemistry, but would not affect survival in p-stage IA disease. Surgeons can be less apprehensive about performing hookwire localization in relation to STAS on stage IA disease suitable for SR.