The role of sarcopenia and adiposity in prognosis of pleural mesothelioma: A CT-based analysis.

Abstract

8053 Background: Pleural mesothelioma (PM) is a rare malignancy associated with asbestos exposure and characterized by an aggressive clinical course and poor prognosis. Identifying clinical and biological prognostic markers is of significant clinical importance. Recently, computed tomography (CT) based body composition parameters have been investigated for their association with survival outcomes in cancer patients; however, their prognostic value in PM remains unclear. This study aimed to evaluate the impact of clinical characteristics and CT-derived body composition parameters on survival in patients with PM. Methods: This retrospective study included 73 patients diagnosed with pleural mesothelioma. CT images were used to calculate the subcutaneous adipose tissue index (SATI), visceral adipose tissue index (VATI), total abdominal adipose tissue index (TATI), skeletal muscle index (SMI), and psoas muscle index (PMI). Patients were classified as sarcopenic or non-sarcopenic based on SMI. Results: The median age was 60 years, and 57.5% of patients were male. Most patients had good performance status (ECOG 0–1), and the epithelioid subtype was the most common histology. Approximately one-third of patients had a history of smoking or prior surgery. In univariate analysis, age ≥60 years was significantly associated with increased mortality. In multivariate analysis, age ≥60 years (HR 2.45) and male sex (HR 2.13) were identified as independent poor prognostic factors. Non-sarcopenic patients had a significantly lower risk of mortality compared with sarcopenic patients (HR 0.37). Additionally, higher TATI values were associated with increased mortality risk (HR 2.26). Kaplan–Meier analysis demonstrated significantly shorter OS in patients aged ≥60 years (Table). Conclusions: In patients with pleural mesothelioma, advanced age and male sex are associated with poorer survival, whereas preserved skeletal muscle mass is associated with improved outcomes. Increased abdominal adiposity is linked to higher mortality risk. CT-based body composition parameters may provide useful prognostic information in patients with PM. Evaluation of the association between parameters and survival using univariate and multivariate analyses. Univariate analysis Multivariate analysis P value HR 95% CI P value HR 95% CI Age (<60y / ≥60y) 0.005 2.27 1.27-4.05 0.005 2.45 1.31-4.61 Gender (female*/male) 0.06 1.65 0.96-2.83 0.011 2.13 1.19-3.81 ECOG PS (0-1*/2-3) 0.35 1.43 0.66-3.07 Histological subtypes (epithelioid / non-epithelioid) 0.26 1.42 0.76-2.66 Stage (I-III*/IV) 0.43 1.26 0.70-2.27 SMI cm 2 /m 2 (sarcopenia*/normal) 0.21 0.70 0.41-1.21 0.007 0.37 0.18-0.76 TATI cm 2 /m 2 (low*/high) 0.30 1.36 0.75-2.48 0.04 2.26 1.03-4.97