Comparison of Survival by Multimodal Treatment Regimen Among Malignant Pleural Mesothelioma Patients in an Integrated Health System.

BACKGROUND: Optimal therapy for malignant pleural mesothelioma (MPM) remains unclear. We compared overall survival in patients with MPM after various multimodal treatment regimens including combinations of immunotherapy, chemotherapy, and surgery. PATIENTS AND METHODS: We examined MPM patients treated within our integrated health system from January 1, 2009 to December 31, 2020. Patients were grouped based on treatment regimen: chemotherapy alone (CT), immunotherapy with or without chemotherapy (iCT), surgery with chemotherapy (sCT), and surgery with immunotherapy and chemotherapy (siCT). We analyzed baseline characteristics and overall patient survival among these groups and several subgroups. RESULTS: One hundred seventy-nine patients were included. Among the study groups, there was no difference in age, sex, race/ethnicity, Charlson Comorbidity Index, or Eastern Cooperative Oncology Group performance status. Patients treated with CT (N = 109), iCT (N = 35), sCT (N = 26), and siCT (N = 9) had median (95% confidence interval) survivals of 11.7 (9.9-16.3), 18.2 (14.5-29.8), 20.7 (11.6-37.2), and 22.6 (19.7-37.8) months, respectively (P < .001). Median survival among patients with and without immunotherapy was 19.7 (17.4-29.8) and 12.3 (10.6-17.3) months, respectively (P = .023). Median survival among patients with and without surgery was 21.7 (17.6-34.8) and 13.6 (11.5-17.3) months, respectively (P = .007). Patients with biphasic/sarcomatoid subtypes who received immunotherapy experienced 76.2% (55.8%-100.0%) 12 month survival vs. 13.6% (4.8%-39.0%) among those who did not (P < .001). CONCLUSION: MPM patients receiving surgery and immunotherapy as part of multimodal treatment regimens experienced the longest survival. Surgery and immunotherapy are each associated with survival. Further investigations are warranted to assess the benefit of immunotherapy within multimodal treatment regimens for MPM.

Improving outcomes in malignant pleural mesothelioma in an integrated health care system.

Background: Malignant pleural mesothelioma (MPM) is a rare and aggressive tumor that should be managed by an experienced surgical and multidisciplinary group. Our objective was to determine the impact of proficient surgeons and MPM bi-disciplinary review on outcomes of patients with MPM. Methods: Through this cohort study, electronic medical records of 368 adult patients with MPM from 1/1/2009 to 12/31/2020 were reviewed and compared before and after MPM surgeries were regionalized to specialized surgeons and bi-disciplinary review of MPM patient treatment options. We used the Kaplan-Meier method and log-rank tests to compare survival rates by period, by treatment type, and by stage. Patients were followed from cancer diagnosis date until they died or end of study follow-up, whichever occurred first. We also conducted Cox proportional hazards regression model to examine the overall survival (OS) with adjustments for age, histology, stage, and Charlson comorbidity index (CCI). Results: Despite similar staging, more patients received any MPM directed treatment from 2015-2020 compared with those patients from 2009-2014. Specifically, there was an increase in patients who received pleurectomy/decortication (PD) from 2015-2020 compared to those who received PD in 2009-2014. Patients with similar age, CCI, stage, and histology had an increase in OS of 12 months with multimodality therapy (surgery, systemic therapy, +/- radiation) compared to those patients who received no treatment. Conclusions: Consolidating mesothelioma surgery to a specialized surgical team and regular bi-disciplinary review of MPM cases to determine appropriate multimodality therapy, increases the incorporation of surgical treatments in the management of patients with MPM.