Intensity modulated radiation therapy after extra-pleural pneumonectomy for malignant pleural mesothelioma is feasible without fatal pulmonary toxicity and provides good survival

Our plain-English summary of Intensity modulated radiation therapy after extra-pleural pneumonectomy for malignant pleural mesothelioma is feasible without fatal pulmonary toxicity and provides good survival, by S. Jhavar, J. Pruszynski, A. Gowan, et al (Asia-Pacific Journal of Clinical Oncology, 2018).

The study

• Authors: S. Jhavar, J. Pruszynski, A. Gowan, T. Boyle, N. Deb, M. Patel
• Journal: Asia-Pacific Journal of Clinical Oncology
• Published: 2018;14(2):e88-e94
• Cited by: 3 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Aim: To analyze patterns of failure, toxicity, relapse-free survival (RFS), and overall survival (OS) in malignant pleural mesothelioma (MPM) patients treated with intensity-modulated radiation therapy following extrapleural pneumonectomy (EPP).

Methods: We reviewed 18 charts of patients with MPM from 2005 to 2014 who underwent EPP followed by hemithoracic intensity-modulated radiation therapy. Intensity-modulated radiation therapy dose delivery adhered to published lung dose constraints. Kaplan-Meier curves were used to assess the RFS and OS. Median survival times are reported for both RFS and OS.

Results: Median age was 65 years (range: 40-76 years). Chemotherapy was administered in four neo-adjuvant and seven adjuvant patients. Pathological American Joint Committee on Cancer stages II, III, IV, surgical margin, lympho-vascular space, pericardium, and chest wall involvement were seen in 3, 12, 3, 9, 7, 12 and 3 patients, respectively. The majority of the patients received 45 Gy in 25 fractions. The mean lung dose was 7.14 Gy (range: 5 Gy-9.3 Gy). The mean V20 was 2.23%. At a median follow-up of 3 years, eight patients were alive (44%); 10 experienced relapse (56%). Median RFS and OS were 24.4 months (95% CI: >16.3 months) and 38.2 months (95% CI: 17.4-78.1 months), respectively. Acute toxicities were fatigue, dermatitis, nausea, esophagitis/dysphagia, cough, and dyspnea on exertion. No grade III, IV, or fatal pulmonary toxicities were observed.

Conclusion: Intensity-modulated radiation therapy following EPP for MPM resulted in RFS and OS comparable to the published literature without significant toxicity.

© 2017 John Wiley & Sons Australia, Ltd.

In plain English

This retrospective cohort study reviewed the charts of 18 patients with malignant pleural mesothelioma treated in 2005 to 2014 at Baylor Scott and White Health, Texas. All had extrapleural pneumonectomy (EPP) surgery, then intensity-modulated radiation therapy (IMRT) to that side of the chest. The study did not report the patients' asbestos exposure. Seventeen of the 18 were men, and the median age was 65. Most patients (14) received 4500 cGy in 25 fractions. Four had chemotherapy before surgery and seven after. No patient required an interruption of radiation treatment because of acute side effects. No grade III acute side effects and no grade III or fatal lung toxicity were observed. Milder effects included fatigue, skin inflammation, nausea, swallowing problems, cough and breathlessness on exertion. At a median follow-up of 3 years, 8 patients (44%) were alive and 10 (56%) had relapsed. Median overall survival was 38.2 months (95% confidence interval 17.4 to 78.1 months), and median relapse-free survival was 24.4 months (95% confidence interval: more than 16.3 months). The authors concluded that survival was comparable to published results without significant toxicity. They noted that their study was retrospective, small and based on carefully selected patients.

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, single-institution cohort study (chart review)
• Who was studied: 18 patients with malignant pleural mesothelioma treated from 2005 to 2014 at Baylor Scott and White Health, Temple, Texas, USA, with extrapleural pneumonectomy followed by hemithoracic IMRT. 17 were male, and the median age was 65 years (range 40 to 76).
• Exposure: The exposure studied was treatment, not asbestos. Patients had extrapleural pneumonectomy, then IMRT (static IMRT in 17 patients, Rapid Arc in 1). Most (14 of 18) received 4500 cGy in 25 fractions. Other patients received schedules from 5000 cGy to 5750 cGy. Chemotherapy was given before surgery in 4 patients and after surgery in 7. Asbestos exposure of these patients was not reported.
• Main results:
  • Of the 18 patients, 17 were male (94.4%).
  • Chemotherapy was given before surgery in 4 patients (22%) and after surgery in 7 patients (39%).
  • The mean lung dose was 7.14 Gy (range 5 to 9.3 Gy). The mean V20, the share of normal lung receiving 20 Gy or more, was 2.23%.
  • No patient required interruption of treatment due to acute toxicity, and no grade III acute toxicities were seen.
  • Grade I or II acute toxicities included fatigue, dermatitis, nausea, esophagitis/dysphagia, cough, and dyspnea on exertion.
  • No grade III or fatal pulmonary toxicity was observed among the 18 patients.
  • At a median follow-up of 3 years, 8 of 18 patients were alive (44%) and 10 had experienced relapse (56%).
  • The authors reported that most relapses were loco-regional, at sites including the mediastinal nodes, contralateral lung/pleura, diaphragm, or the edges of the radiation field.
  • Median overall survival was 38.2 months (95% CI: 17.4 to 78.1 months).
  • Median relapse-free survival was 24.4 months (95% CI: greater than 16.3 months).
  • Survival rates were 66% (12/18) at 2 years, 50% (9/18) at 3 years, and 33% (6/18) at 5 years.
• The authors' conclusion: The authors concluded that IMRT following extrapleural pneumonectomy for malignant pleural mesothelioma resulted in relapse-free and overall survival comparable to the published literature, without significant toxicity.
• Limitations the authors state:
  • The study was retrospective, which the authors called its main limitation.
  • The number of patients was small.
  • Follow-up did not follow a protocol, and toxicity data came from the history and physical examination findings recorded in the charts.
  • Results could be biased by careful patient selection and rigorous presurgical work-up, so they may not apply to surgically unfit patients.

Topics

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

Medical terms in this study, explained in our Lexicon: Pneumonectomy, Pleural Mesothelioma, Overall Survival, Intensity-Modulated Radiation Therapy (IMRT), Extrapleural Pneumonectomy (EPP), Kaplan-Meier Curve, Median Survival, Chemotherapy.

Related studies

• Patterns of failure, toxicity, and survival after extrapleural pneumonectomy and hemithoracic intensity-modulated radiation therapy for malignant pleural mesothelioma — D.R. Gomez, D.S. Hong, et al. (2013)
• Long-term outcomes of intensity-modulated radiotherapy following extra-pleural pneumonectomy for malignant pleural mesothelioma — Y. Matsuo, K. Shibuya, et al. (2017)
• Extra-pleural pneumonectomy in the era of image-guided intensity-modulated radiotherapy — M. Trovo, D. Franceschini, et al. (2019)
• High-dose-rate surface brachytherapy to boost elongated, curvilinear incisional scars after extrapleural pneumonectomy for malignant pleural mesothelioma treated with adjuvant intensity-modulated radiation therapy — L.A. Doyle, T.N. Showalter, et al. (2010)
• Current readings: improvements in intensity-modulated radiation therapy for malignant pleural mesothelioma — K.E. Rosenzweig (2013)
• Intensity-modulated radiotherapy after extrapleural pneumonectomy in the combined-modality treatment of malignant pleural mesothelioma — A. Chi, Z. Liao, et al. (2011)

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