Relapse Patterns and Tailored Treatment Strategies for Malignant Pleural Mesothelioma Recurrence after Multimodality Therapy.

To date, there have been no established therapies for recurrent malignant pleural mesothelioma (MPM) after multimodality treatment. Aims of this retrospective study are to analyze the recurrence pattern, its treatment and to identify the predictors of best oncological outcomes for relapsed MPM, comparing extrapleural pneumonectomy (EPP) vs. pleurectomy/decortication (PD). Study population: 94 patients with recurrence of MPM after multimodality treatment underwent macroscopic complete resection (52.1% with EPP and 47.9% with PD) between July 1994 and February 2020. Distant spread was the most frequent pattern of recurrence (71.3%), mostly in the EPP group, while the PD group showed a higher local-only failure rate. Post-recurrence treatment was administered in 86.2%, whereas best supportive care was administered in 13.8%. Median post-recurrence survival (PRS) was 12 months (EPP 14 vs. PD 8 months, p = 0.4338). At multivariate analysis, predictors of best PRS were epithelial histology (p = 0.026, HR 0.491, IC95% 0.263-0.916), local failure (p = 0.027, HR 0.707, IC95% 0.521-0.961), DFS ≥ 12 months (p = 0.006, HR 0.298, IC95% 0.137-0.812) and post-recurrence medical treatment (p = 0.046, HR 0.101, IC95% 0.897-0.936). The type of surgical intervention seems not to influence the PRS if patients are fit enough to face post-recurrence treatments. In patients with a prolonged disease-free interval, in the case of recurrence the most appropriate treatment seems to be the systemic medical therapy, even in the case of local-only relapse.