Three Decades of Malignant Pleural Mesothelioma: An Academic Center Experience

Our plain-English summary of Three Decades of Malignant Pleural Mesothelioma: An Academic Center Experience, by A. Nasser, A. Baird, M.D. Saint-Pierre, et al (Clinical Lung Cancer, 2021).

The study

• Authors: A. Nasser, A. Baird, M.D. Saint-Pierre, K. Amjadi, S. Laurie, P. Wheatley-Price
• Journal: Clinical Lung Cancer
• Published: 2021;22(5):441-448
• Cited by: 2 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Malignant pleural mesothelioma (MPM) remains a challenging disease to manage. In the past few decades, extrapleural pneumonectomy (EPP), pemetrexed-based chemotherapy, and indwelling pleural catheters were introduced to MPM care with variable levels of efficacy and evidence.

Patients And Methods: This was a retrospective review of patients diagnosed with MPM between January 1991 and March 2019. The primary outcome was overall survival (OS). Data were examined by decade to assess trends in MPM demographics, management, and OS. A subgroup analysis was then conducted to examine the impact of EPP, pemetrexed, and indwelling pleural catheters on OS.

Results: The study included 337 patients; 309 patients had died at last follow-up (91.7%). Median age at diagnosis and the proportion of female patients increased from 65.8 years (interquartile range [IQR], 57.1-73.7) and 11.6% female from 1991 to 1999 to 75 years (IQR, 68.1-80.6) and 20.5% female from 2010 to 2019. Median OS was largely unchanged in the three study periods: 9.0 months (95% confidence interval [CI], 6.9-12.7) in the 1991-1999 cohort, 9.3 months (95% CI, 7.6-13.2) in the 2000-2009 cohort, and 10.1 months (95% CI, 7.9-13.6) in the 2010-2019 cohort. Controlling for a number of demographic and prognostic factors, EPP (hazard ratio [HR] = 0.50; 95% CI, 0.3-0.9; P = .02), pemetrexed-based chemotherapy (HR = 0.59; 95% CI, 0.40-0.87; P = .007), and indwelling pleural catheters (HR = 0.3; 95% CI, 0.13-0.71; P = .006) were each associated with improvements in OS.

Conclusion: Despite the small incremental improvements in survival shown by the three interventions we examined, prognosis remains guarded for MPM patients. Better modalities of management are needed.

Copyright © 2021. Published by Elsevier Inc.

In plain English

This retrospective review covered 337 patients with malignant pleural mesothelioma treated at an academic cancer center in eastern Ontario, Canada, from January 1991 to March 2019. Of these, 178 (52.8%) had known asbestos exposure. By last follow-up, 309 (91.7%) had died. Median overall survival was 9.03 months (95% CI, 6.9-12.7) in 1991-1999, 9.3 months (7.56-13.2) in 2000-2009 and 10.1 months (7.85-13.6) in 2010-2019. Median age at diagnosis rose from 65.8 to 75 years, and the share of women rose from 11.6% to 20.5%. After adjustment for other factors, two treatments were each associated with longer survival. These were extrapleural pneumonectomy (23 patients; hazard ratio 0.5, 95% CI 0.28-0.9) and pemetrexed-based chemotherapy (hazard ratio 0.59, 95% CI 0.40-0.87; not statistically significant before adjustment). Among 92 patients diagnosed June 2012 to March 2019, the 46 with indwelling pleural catheters also survived longer after adjustment (hazard ratio 0.3, 95% CI 0.13-0.71). The authors cautioned that causality cannot be inferred and that surgery patients were highly selected. They also noted that longer survivors may have been likelier to get catheters. The authors concluded that treatment advances had a modest association with survival.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Retrospective review of patient records at a single tertiary academic center
• Who was studied: 337 patients with biopsy-proven malignant pleural mesothelioma treated at one cancer center in eastern Ontario, Canada, from January 1991 to March 2019. Patients with testicular or peritoneal mesothelioma were excluded. 284 (84.3%) were men.
• Exposure: The study examined treatments, not asbestos doses: extrapleural pneumonectomy (EPP), pemetrexed-containing chemotherapy and indwelling pleural catheters. Known asbestos exposure was recorded for 178 of 337 patients (52.8%). Fiber types, products and jobs were not reported.
• Main results:
  • 178 of the 337 patients (52.8%) had known asbestos exposure.
  • By last follow-up, 309 of 337 patients (91.7%) had died.
  • Median overall survival was largely unchanged across the three periods: 9.03 months (95% CI, 6.9-12.7) in 1991-1999, 9.3 months (7.56-13.2) in 2000-2009 and 10.1 months (7.85-13.6) in 2010-2019. Table 1 labels these intervals as 95% CI.
  • Median age at diagnosis rose from 65.8 years in the earliest decade to 72.2 years in the middle decade and 75 years in the last decade.
  • Between the first and last decades, the percentage of female patients rose from 11.6% to 20.5%.
  • The 23 patients who had extrapleural pneumonectomy had a median overall survival of 27.5 months (95% CI, 13-124). Patients who did not have EPP had a median of 9.23 months.
  • After adjusting for age, stage, sex, performance status, histology and other prognostic factors, EPP was associated with improved survival (HR = 0.5; 95% CI, 0.28-0.9; P = .02).
  • Among patients who received chemotherapy, the unadjusted difference in median survival between pemetrexed and non-pemetrexed chemotherapy was not statistically significant (P = .438). The text gives 14.2 months for the pemetrexed group and 12.7 months for the non-pemetrexed group, but Table 2 lists them the other way round.
  • After adjustment for baseline and prognostic factors, pemetrexed-containing chemotherapy was associated with improved overall survival compared with non-pemetrexed chemotherapy (HR = 0.59; 95% CI, 0.40-0.87; P = .007).
  • Catheter data covered only the 92 patients diagnosed between June 2012 and March 2019, of whom 46 (50.0%) had an indwelling pleural catheter. Their survival was 14.2 months, compared with 7.3 months in the other patients. The catheter group was less likely to have stage III or IV disease (30.4% vs. 76.1%).
  • In this 2012-2019 group, after adjustment, indwelling pleural catheters were associated with longer overall survival (HR = 0.3; 95% CI, 0.13-0.71; P = .006).
• The authors' conclusion: The authors concluded that, despite advances in treatment for malignant pleural mesothelioma, these advances have had a modest association with overall survival.
• Limitations the authors state:
  • The study was retrospective, so causality cannot be inferred.
  • The study was limited to the eastern Ontario region.
  • Patients who had EPP were a highly selected group: younger, fitter and with limited disease.
  • The pemetrexed and non-pemetrexed groups were fundamentally different, because the non-pemetrexed patients came from an earlier era.
  • The catheter association may not be causal: patients who lived longer may have been more likely to get catheters. Catheter data were reliably available only from June 2012 onward.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma.

Medical terms in this study, explained in our Lexicon: Pleural Mesothelioma, Extrapleural Pneumonectomy (EPP), Pemetrexed (Alimta), Chemotherapy, Indwelling Pleural Catheter, Overall Survival, confidence interval, Hazard Ratio.

Related studies

• The Thoracic Surgery Service at Memorial Sloan Kettering Cancer Center — V.W. Rusch (2015)
• Three decades of experience in the surgical multi-modality management of pleural mesothelioma — H. Luckraz, M. Rahman, et al. (2010)
• 18F-FDG PET/CT in the management of patients with malignant pleural mesothelioma being considered for multimodality therapy: experience of a tertiary referral center — H.S. Elliott, U. Metser, et al. (2018)
• Treatment Patterns and Outcomes of Patients With Advanced Pleural Mesothelioma at an Academic Referral Centre — S. Schmid, L. Zhan, et al. (2022)
• Evolution of locoregional treatment for peritoneal carcinomatosis: single-center experience of 308 procedures of cytoreductive surgery and perioperative intraperitoneal chemotherapy — T.C. Chua, W. Liauw, et al. (2011)
• Three decades of pleural cancer and mesothelioma registration in Austria where asbestos cement was invented — M. Neuberger, C. Vutuc (2003)

Browse more research in Clinical Lung Cancer, or return to medical research.