Updated Post-Recurrence Survival Outcomes in Patients Undergoing Pleurectomy/Decortication for Pleural Mesothelioma

A. Nakamura¹, M. Hashimoto¹, A. Kuroda¹, K. Takegahara¹, A. Fukuda¹, S. Matsumoto¹, N. Kondo¹, S. Hasegawa², S. Funaki^1
1Hyogo Medical University, Nishinomiya, Hyogo ²Takarazuka City Hospital, Takarazuka, Hyogo

Purpose: Most patients with pleural mesothelioma (PM) experience recurrence. We have previously described clinical outcomes with recurrence after pleurectomy/decortication (P/D) for PM. The purpose of this study is to update our results with a larger cohort of recent patients and to determine post-recurrence survival, prognostic factors, and recurrence patterns after P/D.

Methods: We conducted a retrospective cohort study of 251 patients who underwent neoadjuvant chemotherapy with platinum plus pemetrexed followed by P/D at our hospital between January 2012 and December 2022. Eligibility criteria of multimodality treatment were age epithelioid histologic subtype on pleural biopsy, clinical stage T1-3N0-1M0, Eastern Cooperative Oncology Group performance status of 0 to 1, and no major comorbidity. After multimodality treatment, patients were monitored every 3 months using CT until death. Recurrent diagnoses were determined by a cancer board. A patient who relapsed was administered appropriate treatment according to the patient's condition. Survival and recurrence were calculated using the Kaplan-Meier method with the log-rank test. Clinical factors related to post-recurrence survival were assessed using multivariate analysis with the Cox proportional hazards model.

Results: Of 251 patients, 190 (75.7%) developed recurrence (median follow-up, 30.9 months). The 1- and 3-year recurrence-free survival rates were 77.6% and 27.0%, respectively (median recurrence-free survival time, 21.1 months). The 1- and 3- year overall survival rates were 94.0% and 60.2%, respectively (median survival time, 44.1 months). With regard to initial recurrence, 122 patients (64.2%) developed local recurrence, 16 (8.4%) developed distant recurrence, and 52 (27.4%) developed both local and distant recurrences. One hundred sixty-one patients (84.7%) underwent a post-recurrence treatment. Initial post-recurrence treatment included chemotherapy (n=142), surgery (n=9), radiofrequency ablation (n=5), radiotherapy (n=5). The 1-year post-recurrence survival rate was 60.6% (median post-recurrence survival time, 18.0 months). Multivariate analysis revealed that post-recurrence treatment (hazard ratio, 0.15; 95% confidence interval, 0.085-0.26; P < 0001), local recurrence only (hazard ratio, 0.49; 95% confidence interval, 0.34-0.72; P = 0.003), and disease-free interval more than 12 months (hazard ratio, 0.4; 95% confidence interval, 0.26-0.6; P < 0.0001) were the independent, favorable, and significant prognostic factors of post-recurrence survival.

Conclusion: Most patients who had recurrence after P/D received post-recurrence treatment. Post-recurrence treatment, local recurrence only, and disease-free interval were important prognostic factors of post-recurrence survival. In patients who underwent P/D, the post-recurrence survival was an acceptable outcome.

Identify the source of the funding for this research project: None.