526P Integrin beta-6 (IB6) in focus: Contemporary real-world evidence on prevalence in non-small cell lung cancer (NSCLC)

classification, and staging was based on the 8th TNM system.Overall survival (OS) and disease-free survival (DFS) were compared. Results:The cohort included 173 males (68.7%) and 79 females (31.3%), with a median age of 62.8 years.STAS was present in 148 patients (58.8%).STAS positivity was significantly associated with histological subtype (p = 0.002), being enriched in micropapillary tumors (12.2% vs 1.9%), while lepidic-predominant tumors were more often STAS negative.Lymphovascular and visceral pleural invasion were significantly more frequent in STAS-positive cases (p < 0.01).STAS was also associated with lymph node metastasis, particularly N2 disease (p = 0.013).The worst prognosis was observed in STAS-positive patients undergoing sublobar resection, with a 50% mortality rate, reduced OS (p < 0.014), and increased risk of death (HR 3.37; 95% CI 1.10-10.3).STAS positivity did not significantly affect OS after lobar resection.DFS did not differ between resection types.Conclusions: STAS is a strong adverse prognostic factor in pulmonary adenocarcinoma, particularly after sublobar resection.STAS status should be considered when determining surgical extent and postoperative management.Further studies are needed to clarify its role in staging and treatment strategies.