RT Journal Article
SR Electronic
T1 Non-solid neoplastic nodules are associated with low PD L1 expression
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP PA4816
DO 10.1183/13993003.congress-2019.PA4816
VO 54
IS suppl 63
A1 Giulia Maria Stella
A1 Chandra Bortolotto
A1 Filippo Antonacci
A1 Roberto Dore
A1 Manuela Coretti
A1 Ciuffreda Antonio
A1 Carnevale Sergio
A1 Morbini Patrizia
YR 2019
UL http://erj.ersjournals.com/content/54/suppl_63/PA4816.abstract
AB Few data are known on the molecular features characterizing neoplastic lesions presenting as non-solid nodules (NSN), the specific pattern of tumour presentation and growth. We retrospectively reviewed the CT scans of 36 patients who underwent transthoracic CT-guided fine needle aspiration of suspected NS pulmonary lesions from october 2016 to december 2017 who received a final diagnosis of malignancy. Exhaustive clinical and radiological features were available for each case. In all cases the diagnosis of adenocarcinoma (ADC) was reached. EGFR mutations were identified in 2 of the 28 cases (7%) with adequate material (one exon 19 deletion and L858R); no case showed ALK/EML1 or ROS1 translocations. PD-L1 immunostains could be evaluated in 30 cytological samples, while the remaining 7 did not reach the cellularity threshold for evaluation. TPS was <1% in 26 cases, >1%<50% in 3, and >50% in 1. All surgical samples showed TPS <1%. Of the 17 cases that could be evaluated on both samples, 15 were concordantly TPS 0, and 2 showed TPS >1%<50 on the biopsy samples. Overall PD-L1 immunostains documented the predominance of low/negative TPS, with high concordance in FNA and corresponding surgical samples. It can be hypothesized that lung ADC with NSN pattern and predominant in situ (i.e. lepidic) components represent the first steps in tumor progression, which have not yet triggered immune response, and/or have not accumulated a significant rate of mutations and neoantigen production, or that they belong to the infiltrated-excluded category of tumors. The negative prediction of response to immunomodulating therapy underlines the importance of rapid surgical treatment of these lesionsFootnotesCite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA4816.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).