Impact of Pleural Lavage Cytology Positivity on Early Recurrence After Surgery for Non-Small Cell Lung Cancer

Objective: The aim of this study was to elucidate the impact of pleural lavage cytology positivity on early recurrence in patients operated on non -small cell lung cancer (NSCLC). Methods: This is a multicentre prospective cohort study of 684 patients undergoing an anatomical lung resection for NSCLC between October 2015 and October 2017 at 12 national centres. A pleural lavage was performed before and after lung resection. The association between the different predictors of early recurrence and PLC positivity was performed using univariate and multivariate logistic regression models. A propensity score analysis was performed by inverse probability weighting (IPSW) using average treatment effect (ATE) estimation to analyse the impact of PLC positivity on early recurrence. Results: Overall PLC positivity was observed in 15 patients (2.2%). After two years, 193 patients (28.2%) relapsed, 182 (27.2%) with a negative PLC and 11 (73.3%) with a positive PLC (p < 0.001). Factors associated to early recurrence were adenocarcinoma histology (OR = 1.59, 95%CI 1.06-2.38, p = 0.025), visceral pleural invasion (OR = 1.59, 95%CI 1.04-2.4, p = 0.03), lymph node involvement (OR = 1.84, 95%CI 1.14-2.96, p = 0.013), advanced pathological stage (OR = 2.12, 95%CI 1.27-3.54, p = 0.004) and PLC positivity (OR = 4.14, 95%CI 1.25-16.36, p = 0.028). After IPSW, PLC positivity was associated with an increased risk of early recurrence (OR = 3.46, 95%CI 2.25-5.36, p < 0.001). Conclusions: Positive pleural lavage cytology was found to be the strongest predictor of early recurrence. (c) 2023 SEPAR. Published by Elsevier Espana, S.L.U. All rights reserved.