Survival after conservative (palliative) management of pleural malignant mesothelioma

Our plain-English summary of Survival after conservative (palliative) management of pleural malignant mesothelioma, by N. Merritt, C.J. Blewett, J.D. Miller, et al (Journal of Surgical Oncology, 2001).

The study

• Authors: N. Merritt, C.J. Blewett, J.D. Miller, W.F. Bennett, J.E. Young, J.D. Urschel
• Journal: Journal of Surgical Oncology
• Published: 2001;78(3):171-4
• Cited by: 67 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background And Objectives: Malignant mesothelioma is a lethal disease. Aggressive multimodality treatment protocols are reportedly associated with improved survival, but the apparent survival benefits may simply reflect patient selection and the variable natural history of this malignancy. Before embarking on our own protocol of experimental treatment for mesothelioma, we sought to identify important prognostic factors and document the survival of patients treated conservatively (with palliative intent only) in our region.

Methods: We performed a retrospective review of all patients with a diagnosis of malignant mesothelioma seen at our center between 1987 and 1999. Since curative intent treatment had not been given, we assumed that measured survival would largely reflect the natural history of the malignancy.

Results: There were 101 patients (80 males and 21 females). Mean age was 65 +/- 9.2 years. Symptoms of disease were present for a median time of 5 months before the diagnosis was established. The most common presenting symptoms were dyspnea (46 patients), chest pain (30 patients), and weight loss (22 patients). Sixty-eight patients (68%) had a history of asbestos exposure. Mesothelioma subtypes included epithelial (43 patients), sarcomatous (26 patients), mixed (19 patients), desmoplastic (4 patients), and unspecified (9 patients). All 101 patients were treated with palliative intent. Talc pleurodesis was performed in 70 patients. At the time of analysis, 90 patients had died and 11 remained alive. Median survival was 213 (95% CI 137-289) days. Survival for the three major histological subtypes was significantly different (log rank, P = 0.0016). Histological subtype (epithelial favorable) was the only significant independent prognostic factor (Cox proportional hazard regression, P = 0.0009).

Conclusions: Patients with epithelial mesothelioma survive longer than those with other histological subtypes. Conservatively managed patients with pleural malignant mesothelioma have a median survival of approximately 7 months. These data from conservatively treated patients can serve as baseline information for future studies of experimental treatments.

Copyright 2001 Wiley-Liss, Inc.

In plain English

This was a retrospective review of 101 patients (80 males, 21 females) diagnosed with malignant mesothelioma of the pleura between 1987 and 1999 at two centres in Hamilton, Ontario, Canada, all treated with palliative intent only. Talc pleurodesis was done in 70, radiotherapy in 30 and chemotherapy in 9. Sixty-eight patients (68%) had a history of asbestos exposure. No fiber types or jobs were reported. At analysis, 90 patients had died. Median survival from diagnosis was 213 days (95% CI 137 to 289). By subtype, median survival was 239 days (95% CI 58 to 420) for epithelial, 83 days (95% CI 39 to 127) for sarcomatous and 264 days (95% CI 191 to 337) for mixed mesothelioma. The epithelial group had the highest one-year and long-term survival. Epithelial histology was the only independent predictor of survival. Palliative treatments did not significantly affect survival. The authors concluded that median survival with conservative management was approximately 7 months and that these data can serve as a baseline for studies of experimental treatments. They could not stage patients or measure quality of palliation.

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 (case series) of patients' charts, with Kaplan-Meier survival analysis, log-rank comparisons and Cox proportional hazards regression
• Who was studied: 101 patients (80 males, 21 females; age at diagnosis 43 to 84 years, mean 65) diagnosed with malignant mesothelioma of the pleura at the Hamilton Regional Cancer Centre and St. Joseph's Hospital, Hamilton, Ontario, Canada, between 1987 and 1999. All were treated with palliative intent only.
• Exposure: Asbestos exposure was not the focus of the study. 68 of 101 patients (68%) had a history of asbestos exposure, with no fiber types, products, jobs or doses given. The treatments studied were palliative: talc pleurodesis (70 patients), radiotherapy for symptom control (30 patients, only 2 receiving over 20 Gy) and chemotherapy (9 patients).
• Main results:
  • All 101 patients: at the time of analysis, 90 had died and 11 were alive. Median survival was 213 days (95% CI 137 to 289).
  • Survival was measured from the date of diagnosis. The authors gave the median as 7 months from that date, and contrasted this with other studies that measured survival from symptom onset.
  • Median survival differed significantly by histological subtype (log rank, P = 0.0016): 239 days (95% CI 58 to 420) for epithelial, 83 days (95% CI 39 to 127) for sarcomatous and 264 days (95% CI 191 to 337) for mixed mesothelioma.
  • The mixed group had a slightly longer median survival, but patients with epithelial histology had the highest one-year and long-term survival.
  • In Cox regression, histology (epithelial favorable) was the only significant independent prognostic factor (P = 0.0009). No other factor explained the occasional patient who survived several years.
  • Palliative treatments (pleurodesis, radiotherapy, chemotherapy) had no significant impact on survival (P value printed as 0.59).
  • Subtype was specified in 92 of 101 patients: 43 epithelial, 26 sarcomatous, 19 mixed and 4 desmoplastic.
  • Symptoms were present for a median of 5 months before diagnosis. The most common presenting symptoms were dyspnea (46 patients), chest pain (30) and weight loss (22).
• The authors' conclusion: The authors concluded that conservatively managed patients with pleural malignant mesothelioma had a median survival of approximately 7 months, with epithelial histology the only significant prognostic factor. They considered this survival inferior to that reported after surgical resection, but noted that the apparent benefit of aggressive treatment could be explained by patient selection. They stated that their data serve as baseline information for future studies of experimental treatments.
• Limitations the authors state:
  • Patients were not rigorously staged at diagnosis and could not be staged reliably in retrospect, so no stage data are presented.
  • The authors could not properly assess the quality of palliation in their patients.
  • There were no precise data on regional versus systemic disease at the time of death.
  • The desmoplastic and unspecified subgroups were too small for survival comparisons.

Topics

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

Medical terms in this study, explained in our Lexicon: Palliative Care, Malignant Mesothelioma, Mesothelioma, Dyspnea, Asbestos Exposure, Desmoplastic Mesothelioma, Talc Pleurodesis, Median Survival.

Related studies

• Re-evaluating the role of palliative radiotherapy in malignant pleural mesothelioma — P. Jenkins, R. Milliner, et al. (2011)
• Symptom burden in mesothelioma patients admitted to home palliative care — S. Mercadante, D. Degiovanni, et al. (2016)
• High-dose palliative radiotherapy for malignant pleural mesothelioma — F. Foroudi, J.G. Smith, et al. (2017)
• Palliative treatment of malignant pleural effusions — D. Horn, D. Dequanter, et al. (2010)
• Nonselective transarterial chemoperfusion: a palliative treatment for malignant pleural mesothelioma — T.J. Vogl, S. Lindemayr, et al. (2013)
• Thoracoscopic palliative treatment of malignant pleural effusions: results in 273 patients — K. Arapis, R. Caliandro, et al. (2006)

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