Maintenance pemetrexed after platinum pemetrexed chemotherapy and survival outcomes in malignant pleural mesothelioma in a multicenter real world study

Scientific Reports 2026 July 15 [Link]

Okan Aydin, Zehra Sucuoglu Isleyen, Mert Erciyestepe, Ahmet Emin Ozturk, Sermin Dinc Sonusen, Tugay Atasever, Simay Cokgezer, Ebru Cicek, Ayse Gul Satman Durmaz, Lamia Seker Can, Gozde Balkaya Aykut, Tuba Baydas, Miray Aydogan, Seval Ay Ersoy, Muhammed Mustafa Atci, Kayhan Erturk

Abstract

Malignant pleural mesothelioma (MPM) is an aggressive malignancy with poor prognosis, and the role of maintenance therapy after first-line platinum-pemetrexed chemotherapy remains unclear. We conducted a multicenter retrospective study including 96 patients with metastatic or unresectable MPM treated across eight tertiary oncology centers. Eligible patients had received at least four cycles of first-line platinum-pemetrexed and achieved disease control, after which they were either administered maintenance pemetrexed (n = 54) or observed without further treatment (n = 42). Maintenance pemetrexed was associated with significantly prolonged median progression-free survival (15.5 vs. 7.9 months; p < 0.001) and overall survival (22.3 vs. 16.4 months; p = 0.002) compared with observation. Multivariate analyses confirmed maintenance pemetrexed as an independent predictor of improved progression-free survival (HR 2.92; 95% CI 1.81-4.72; p < 0.001) and overall survival (HR 2.10; 95% CI 1.24-3.55; p = 0.005). Non-epithelioid histology was independently associated with worse outcomes. Subgroup analyses demonstrated that the survival benefit of maintenance pemetrexed persisted in patients achieving both partial response and stable disease after first-line chemotherapy. Importantly, maintenance therapy was well tolerated, with no discontinuations due to toxicity, highlighting its feasibility in routine practice. These real-world findings suggest that maintenance pemetrexed may be associated with improved survival outcomes in patients with MPM who achieve disease control after first-line therapy.