Ricaratterizzazione immuno-molecolare nel carcinoma polmonare non a piccole cellule in progressione: ruolo della toracoscopia medica e confronto con la prima procedura diagnostica e la biopsia liquida

Immune-molecular retyping (IMR) in NSCLC progression with medical thoracoscopy (MT): a valid option? Lung cancer - management, Pleura, Lung cancer P. Meneghin1, M. Daverio1, D. Scattolin1, G. Pasello2, F. Calabrese1, G. Bartolucci1, M. Damin1, D. Biondini1, M. Tinè1 1Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padova -Padova (Italy), 2Department of Surgery Oncology and Gastroenterology, University of Padova -Padova (Italy), BACKGROUND:biopsies for IMR of NSCLC are increasingly needed to personalize cancer treatment after disease progression. Due to its safety profile and the high quality of samples, MT is an attractive option. Moreover, this indication for MT is not currently codified. AIM:to assess the potential advantages of MT in IMR in terms of diagnostic and therapeutic quality and completeness compared to the first diagnostic sample and liquid biopsy(LB). METHODS:MT performed for IMR in our center (2021-2023) were reviewed. Pathological data of IMR of NSCLC were analyzed and compared with the results of histological samples at diagnosis and, when available, LB. RESULTS: 14 patient(pts) underwent MT for IMR in known NSCLC (70±11 years, 58% males) diagnosed by bronchoscopy (n=3 bronchial and n=3 transbronchial biopsies, n=5 EBUS-TBNA) or CT-guided needle biopsy (n=8). The first diagnosis were 13 adenocarcinomas(ADCs) and 1 squamous cell carcinoma(SCC). Pleural biopsies confirmed all histologic cases of ADCs, while in the SCC MT diagnosed a sarcomatoid mesothelioma. However, in 10/18 cases (55%) the Immune-Molecular (IM) status changed, in particular the mutational status of biomarkers in EGFR (3/18 cases), ALK-ROS1 (4/18 cases), MET (1/18 cases), KRAS (1/18 cases). PD-L1 percentage expression changed in 6/18 (61%), of them 4 became positive. MT provided an extended biomarker panel in 10/13 cases, wider than first (1/13; p=0.0003). LB was performed in 5 pts, but 2/5 could not identify molecular mutations found in MT. Only one complication was registered over 14 MT (extended subcutaneous emphysema). CONCLUSIONS: MT is a valid option for immune-molecular retyping in NSLC with pleural progression.