Important prognostic factors in patients with malignant pleural mesothelioma, managed surgically

Our plain-English summary of Important prognostic factors in patients with malignant pleural mesothelioma, managed surgically, by V.W. Rusch, E.S. Venkatraman (The Annals of Thoracic Surgery, 1999).

The study

• Authors: V.W. Rusch, E.S. Venkatraman
• Journal: The Annals of Thoracic Surgery
• Published: 1999;68(5):1799-804
• Cited by: 194 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: The factors influencing outcome after resection of malignant pleural mesothelioma (MPM) are controversial. This analysis of a prospective surgical database identifies important prognostic factors.

Methods: Tumors were staged by the International Mesothelioma Interest Group staging system, and patients were followed until death. Prognostic factors were analyzed by log rank and Cox regression, and were considered significant if p was less than 0.05.

Results: From Oct 1983 to May 1998, 231 patients underwent thoracotomy, 115 had extrapleural pneumonectomy (EPP), and 59 pleurectomy/decortication (P/D). Among patients having EPP or P/D, 142 received adjuvant therapy. The median survival for stage I tumors was 29.9 months, for stage II 19 months, for stage III 10.4 months, and for stage IV 8 months. By multivariate analysis, stage, histology, gender, adjuvant therapy, but not the type of surgical resection, were significant.

Conclusions: The better survival previously reported for P/D compared with EPP is not seen in a large database with long follow-up. Stages I and II have better survival rates than generally assumed for MPM. Locally advanced T and N status, and nonepithelial histology, identify poor prognosis patients who should be considered for novel treatment regimens.

In plain English

This study analyzed a prospective surgical database at Memorial Sloan-Kettering Cancer Center. It covered 231 consecutive patients with malignant pleural mesothelioma who underwent exploratory chest surgery (thoracotomy) between October 1983 and May 1998. Known asbestos exposure was recorded for 138 of the 192 men and 5 of the 39 women. Of the 231 patients, 115 had all visible tumor removed by extrapleural pneumonectomy and 59 by pleurectomy/decortication. Median survival was 29.9 months for stage I, 19 months for stage II, 10.4 months for stage III and 8 months for stage IV tumors. Stage I and stage II did not differ significantly. Better survival was associated with pure epithelial tumors, no lymph node spread, female gender and adjuvant therapy. Stage, histology, gender and adjuvant therapy all remained significant in a multivariate analysis. The type of operation made no significant difference. The authors concluded that stage I and II tumors had better survival than previously assumed, and that surgery and adjuvant therapy may improve survival. They cautioned that few patients had T1 tumors or went without adjuvant therapy.

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: Analysis of a prospective surgical database (registry) of consecutive patients operated on by one surgeon, examining prognostic factors with univariate and multivariate (Cox proportional hazards) survival analysis
• Who was studied: 231 consecutive patients (192 men, 39 women; median age 62) with biopsy-proven malignant pleural mesothelioma who underwent thoracotomy at Memorial Sloan-Kettering Cancer Center, New York, from October 1983 to May 1998
• Exposure: The study examined prognostic factors (stage, T and N status, histology, gender, platelet count, type of surgery, adjuvant therapy) rather than asbestos exposure. Known asbestos exposure was reported for 138 of 192 men (71.8%) and 5 of 39 women (12.8%). No fiber types were named.
• Main results:
  • Of 231 patients, 174 (75%) had a complete resection: 115 by extrapleural pneumonectomy and 59 by pleurectomy/decortication
  • 30-day operative mortality was 3.5% (8/231) overall and 5.2% (6/115) among extrapleural pneumonectomy patients
  • Median survival was 29.9 months for stage I tumors
  • Stage I survival was not significantly different from the 19-month median for stage II (p = 0.163); stage II versus stage III differed significantly (p = 0.002)
  • Median survival was 10.4 months for stage III and 8 months for stage IV; this difference approached significance (p = 0.074)
  • Pure epithelial tumors had significantly better survival than the combined group of mixed, fibrosarcomatous and desmoplastic tumors (p less than 0.01)
  • N0 tumors (no lymph node metastases) had significantly better overall survival than tumors with nodal metastases
  • Among 109 patients with node counts, those with three or fewer positive nodes survived longer than those with four or more (p less than 0.01)
  • Female gender was associated with better overall survival (p less than 0.01)
  • Adjuvant therapy was associated with significantly better survival in completely resected patients (142 received it, 24 did not, among 166 with complete information)
  • Survival did not differ significantly between extrapleural pneumonectomy and pleurectomy/decortication
  • An elevated preoperative platelet count was not associated with poorer survival (p = 0.37)
  • In multivariate analysis, stage, histology, adjuvant therapy and gender were all significant
• The authors' conclusion: The authors concluded that stage I and II tumors have more favorable survival than previously assumed, and that surgical resection and adjuvant therapy may improve survival
• Limitations the authors state:
  • The small number of patients with T1 tumors made the T1 versus T2 comparison less reliable
  • The adjuvant therapy result needs caution because few patients received no postoperative treatment and the types of adjuvant therapy differed
  • The number of lymph nodes examined was not always recorded
  • Median follow-up was relatively short (9.6 months, range 0 to 95)
  • The finding on number of positive nodes is new and needs validation in larger numbers of patients

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, Mesothelioma, Staging, Thoracotomy, Extrapleural Pneumonectomy (EPP), Pleurectomy/Decortication (P/D), Adjuvant Therapy, Median Survival.

Related studies

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• Prognostic coronary surgery in a case of malignant mesothelioma previously managed with trimodality treatment — V. Dhurandhar, B.M. Robinson, et al. (2014)
• Extrapleural pneumonectomy for malignant pleural mesothelioma: outcomes of treatment and prognostic factors — T.D. Yan, M. Boyer, et al. (2009)
• Specimen weight and volume: important predictors of survival in malignant pleural mesothelioma — D.Y. Kircheva, A.N. Husain, et al. (2016)
• Low calretinin expression and high neutrophil-to-lymphocyte ratio are poor prognostic factors in patients with malignant mesothelioma undergoing extrapleural pneumonectomy — S.C. Kao, S. Klebe, et al. (2011)
• Poor Prognostic Factors in Patients with Malignant Pleural Mesothelioma Classified as Pathological Stage IB According to the Eighth Edition TNM Classification — T. Takuwa, M. Hashimoto, et al. (2018)

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