Prognostic Score of Long-Term Survival After Surgery for Malignant Pleural Mesothelioma: A Multicenter Analysis

Our plain-English summary of Prognostic Score of Long-Term Survival After Surgery for Malignant Pleural Mesothelioma: A Multicenter Analysis, by G. Leuzzi, F. Rea, L. Spaggiari, et al (The Annals of Thoracic Surgery, 2015).

The study

• Authors: G. Leuzzi, F. Rea, L. Spaggiari, G. Marulli, I. Sperduti, G. Alessandrini, M. Casiraghi, P. Bovolato, G. Pariscenti, M. Alloisio, M. Infante, V. Pagan, P. Fontana, A. Oliaro, E. Ruffini, G.B. Ratto, G. Leoncini, R. Sacco, F. Mucilli, F. Facciolo
• Journal: The Annals of Thoracic Surgery
• Published: 2015;100(3):890-7
• Cited by: 18 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Despite ongoing efforts to improve therapy in malignant pleural mesothelioma, few patients undergoing extrapleural pneumonectomy experience long-term survival (LTS). This study aims to explore predictors of LTS after extrapleural pneumonectomy and to define a prognostic score.

Methods: From January 2000 to December 2010, we retrospectively reviewed clinicopathologic and oncological factors in a multicenter cohort of 468 malignant pleural mesothelioma patients undergoing extrapleural pneumonectomy. LTS was defined as survival longer than 3 years. Associations were evaluated using χ(2), Student's t, and Mann-Whitney U tests. Logistic regression, Cox regression hazard model, and bootstrap analysis were applied to identify outcome predictors. Survival curves were calculated by the Kaplan-Meier method. Receiver operating characteristic analyses were used to estimate optimal cutoff and area under the curve for accuracy of the model.

Results: Overall, 107 patients (22.9%) survived at least 3 years. Median overall, cancer-specific, and disease-free survival times were 60 (95% confidence interval [CI], 51 to 69), 63 (95% CI, 54 to 72), and 49 months (95% CI, 39 to 58), respectively. At multivariate analysis, age (odds ratio, 0.51; 95% CI, 0.31 to 0.82), epithelioid histology (odds ratio, 7.07; 95% CI, 1.56 to 31.93), no history of asbestos exposure (odds ratio, 3.13; 95% CI, 1.13 to 8.66), and the ratio between metastatic and resected lymph nodes less than 22% (odds ratio, 4.12; 95% CI, 1.68 to 10.12) were independent predictors of LTS. According to these factors, we created a scoring system for LTS that allowed us to correctly predict overall, cancer-specific, and disease-free survival in the total sample, obtaining two different groups with favorable or poor prognosis (area under the curve, 0.74; standard error, 0.04; p < 0.0001).

Conclusions: Our prognostic model facilitates the prediction of LTS after surgery for malignant pleural mesothelioma and can help to stratify the outcome and, eventually, tailor postoperative treatment.

Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

In plain English

This retrospective study reviewed records of 518 patients with malignant pleural mesothelioma who had extrapleural pneumonectomy (removing lung, pleura, half the diaphragm and pericardium) at nine Italian centers between 2000 and 2010. After excluding 50 deaths within 90 days, 107 of the remaining 468 (22.9%) survived at least 3 years. Comparisons used 395 patients followed at least 36 months. Among the 281 with recorded exposure histories, asbestos exposure was reported by 172 shorter-term survivors (83.1%; 35 reported none) and 53 three-year survivors (71.6%; 21 reported none). In multivariate analysis, independent predictors of 3-year survival were younger age, epithelioid tumor type (odds ratio 7.07; 95% CI 1.56 to 31.93), no history of asbestos exposure (odds ratio 3.13; 95% CI 1.13 to 8.66) and fewer than 22% of removed lymph nodes containing cancer (odds ratio 4.12; 95% CI 1.68 to 10.12). A 1-to-12-point score built from these factors exceeded 6 in 93.5% of 3-year survivors and 54.3% of shorter-term survivors. The authors concluded the score could help stratify outcomes; they cited the retrospective design and unstandardized treatment, and called for validation.

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 multicenter cohort study (review of clinical and surgical records) developing a prognostic score
• Who was studied: 518 patients with malignant pleural mesothelioma who had extrapleural pneumonectomy at nine Italian centers, January 2000 to December 2010. 50 who died within 90 days of surgery were excluded, leaving 468 (median age 61, range 31 to 79). The 395 patients with at least 36 months of follow-up were used for the outcome analysis, 107 of whom were long-term survivors. Asbestos exposure history was recorded for 281 of the 395.
• Exposure: History of asbestos exposure, recorded only as yes or no and studied as one of several predictors of survival after surgery. Fiber types, sources, jobs and doses were not reported.
• Main results:
  • 107 of the 468 patients (22.9%) survived at least 3 years after surgery.
  • Among the 281 patients with a recorded exposure history, asbestos exposure was reported by 172 short-term survivors (83.1%; 35 reported none) and by 53 long-term (3-year) survivors (71.6%; 21 reported none).
  • In multivariate analysis, no history of asbestos exposure was an independent predictor of surviving at least 3 years (odds ratio 3.13; 95% CI 1.13 to 8.66).
  • Epithelioid tumor type was an independent predictor of surviving at least 3 years (odds ratio 7.07; 95% CI 1.56 to 31.93).
  • A ratio of cancer-containing to removed lymph nodes below 22% was an independent predictor of surviving at least 3 years (odds ratio 4.12; 95% CI 1.68 to 10.12).
  • Younger age was an independent predictor of surviving at least 3 years (odds ratio 0.51 for the age variable; 95% CI 0.31 to 0.82).
  • For recurrence across the whole sample, only non-epithelioid tumor type (hazard ratio 3.02; 95% CI 1.63 to 5.59) and the lymph node ratio (hazard ratio 2.24; 95% CI 1.43 to 3.52) were independent predictors.
  • In the long-term survivor group, median overall, cancer-specific and disease-free survival were 60, 63 and 49 months. In the short-term group they were 14, 16 and 11 months.
  • The score ranged from 1 to 12 points, with an optimal cutoff of 6 points (area under the curve 0.74; standard error 0.04). 93.5% of long-term survivors scored above 6, compared with 54.3% of short-term survivors.
• The authors' conclusion: The authors concluded that younger age, no history of asbestos exposure, epithelioid histology and a low rate of cancer-containing lymph nodes are associated with better survival after extrapleural pneumonectomy. They said a score built from these factors could help clinicians stratify outcomes and possibly tailor treatment after surgery.
• Limitations the authors state:
  • The study was retrospective.
  • Treatment was not standardized across the participating centers.
  • The study had no data on genetic or molecular factors.
  • The score has not been validated; the authors call for larger prospective studies.

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), Disease-Free Survival, confidence interval, Multivariate Analysis, Odds Ratio, Epithelioid, Histology.

Related studies

• Extrapleural pneumonectomy for malignant mesothelioma: an Italian multicenter retrospective study — L. Spaggiari, G. Marulli, et al. (2014)
• Long-term Survival and Propensity Score Matched Outcomes of Bilateral vs. Unilateral Diaphragm Interventions in Cytoreductive Surgery plus Intra-peritoneal Chemotherapy — B. Singh, G. Singh, et al. (2018)
• Predictors of long-term survival following radical surgery for malignant pleural mesothelioma — A. Nakas, D. Waller (2014)
• Long term survival and perioperative propensity score matched outcomes of diaphragmatic resections compared to stripping in cytoreductive surgery + intra-peritoneal chemotherapy — B. Singh, G. Singh, et al. (2020)
• Does surgery improve survival of patients with malignant pleural mesothelioma?: a multicenter retrospective analysis of 1365 consecutive patients — P. Bovolato, C. Casadio, et al. (2014)
• Long-term survival outcomes of cytoreductive surgery and perioperative intraperitoneal chemotherapy: Single-institutional experience with 1225 cases — L.S. Kyang, N.A. Alzahrani, et al. (2019)

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