2204P Clinical predictors and inflammatory markers for malignant pleural mesothelioma prognosis: A retrospective study in a Spanish Medical Oncology Unit

Malignant pleural mesothelioma (MPM) is a rare thoracic malignancy with bad prognosis. Asbestos exposure has been described as the main risk factor with a key role in its pathogenesis. The aim of this study is to identify the impact of systemic inflammation biomarkers as clinical prognostic factors for MPM. Patients (pts) diagnosed of MPM from 2004 to 2023 from a Medical Oncology Intercenter Unit in Malaga (Spain) were enrolled. We analyzed epidemiologic, clinical and pathological characteristics and correlated them with survival outcomes. Among the 140 pts, median age was 70 years (range 23-94), ECOG 0-1 in 76,4% (n=104), mainly males (70,7%, n=99). 95 pts (67,9%) were epithelioid subtype. Median follow up was 21,6 months (mo) (range 1-217). Median overall survival (OS) 13,5 mo (CI 95% 9,6-17,4), progression-free survival (PFS) 10,1 mo (CI 95% 7,2-13). 19 pts (13,6%) were considered for surgery. In non-resectable pts (n=121, 86,4%), age over 65, malnutrition and ECOG 2-4 at diagnosis were associated to poor OS (21,6 mo CI95% 14,4-28,8; 7,1 mo, CI95% 5,8-8,2; 4,7 mo, CI95% 3-6,5 respectively). Inflammatory biomarkers including high LDH or CRP, neutrophilia, Lung Immune Prognostic Index (LIPI) intermediate-poor, and high dNLR suggested a trend towards poor survival (9,5 mo CI 95% 3,5-15,4; 8,5 mo CI 95% 4,5-12,5; 7,1 mo CI 95% 1,5-3,9; 9,5 mo CI95% 4,5-14,4; 9,5 mo CI95% 4,8-14, respectively; p>0.5). Anemia, moderate-to-severe value of neutrophil to lymphocyte ratio (NLR≥6) and not receiving immunotherapy were significantly associated with worse prognosis. Multivariate analysis showed age and NLR value as independent prognostic factors (p<0.01). Host inflammation status at diagnosis may be a subrogate biomarker of survival for MPM, even for pts not receiving immunotherapy. Modulating the immune system and inflammatory pathways appear as promising strategies for increasing effectiveness in MPM treatment.Table: 2204PUnivariate analysisMultivariate analysisHRCI 95%PHRCI 95%PAge ≤650,560,36-0,880,010,440,23-0,820,01ECOG1,651,3-2,60,00--0,37Malnutrition0,470,29-0,740,00--0,78Anemia9,860,76-0,960,01--0,29High C reactive protein1,870,77-4,520,16---Neutrophilia2,380,31-18,410,40---High LDH1,470,93-2,340,09---NLR (absent-mild vs moderate severe)0,50,28-0,900,020,300,14-0,610,00dLNR (high vs normal)0,910,58-1,420,69---LIPI score (good vs intermediate-poor)1,470,96-2,270,07---Immunotherapy0,480,24-0,960,04--0,62 Open table in a new tab