Author of

• 12736

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  P3.14 - Poster Session 3 - Mesothelioma (ID 197)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Mesothelioma
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/30/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 12740

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    P3.14-004 - Adjuvant Hemithoracic Radiotherapy After Extrapleural Pneumonectomy For Malignant Pleural Mesothelioma: Experience At The Sydney Cancer Centre (ID 1249)

    09:30 - 09:30  |  Author(s): R.H. Lin
    • Abstract

    Background
    Radiotherapy reduces local recurrence following extrapleural pneumonectomy (EPP), and forms part of a potentially curative, multimodality treatment of malignant pleural mesothelioma. Hemithoracic radiotherapy poses a significant dosimetric challenge. Conventional techniques have suffered with marked dose uncertainty, while modern IMRT techniques have been associated with increased pulmonary toxicity. We conducted a retrospective review of all patients referred to our institution for hemithoracic radiotherapy following EPP, with the aim of assessing treatment toxicity and outcomes. The present study is, to our knowledge, the largest Australian series of adjuvant radiotherapy for this disease.

    Methods
    53 patients were referred following EPP for malignant pleural mesothelioma, with or without neoadjuvant chemotherapy, between 2004 and 2012. 4 patients were excluded or did not commence radiotherapy due to poor performance (n = 3) or disease progression (n = 1). Radiotherapy involved a 3D conformal, mixed photon and electron technique, delivering 45-55 Gy in 25-28 fractions (2004-2009, n=31), and a 9-field IMRT technique, delivering 50.4-60 Gy in 28-30 fractions (2009-2012, n=18). We assessed toxicity, disease progression and survival in all patients who commenced radiotherapy (n = 49). Toxicity was assessed using the Common Terminology Criteria for Adverse Events version 4.0 and survival was calculated from the date of EPP using the Kaplan-Meier method.

    Results
    31 patients (59%) received neoadjuvant chemotherapy, with a combination of platinum agent and pemetrexed. 41 patients (84%) completed treatment as prescribed. 6 patients stopped prematurely due to toxicity, and 2 due to disease progression. Most patients discontinuing due to toxicity (n = 5) received over 90% of the prescribed dose. Low grade nausea, anorexia and fatigue were near universal, however severe (grade 3) skin toxicity, nausea and oesophagitis were 8%, 6% and 2%, respectively. One patient developed a grade 4 Pneumocystis carinii infection, however there were no cases of radiation pneumonitis. Late toxicities were rare, with the exception of a persistent elevation in the liver enzymes alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT). Of the patients treated with right-sided disease (n = 26), 9 (35%) developed grade 2-3 elevations in ALP or GGT. Grade 2-3 liver toxicity was more common in patients treated with a conventional technique (53%) than with IMRT (11%). No patients developed clinical hepatitis. With a median follow up of 19 months (range 2-102 months), median progression-free survival and overall survival were 22 and 30 months, respectively. 2-year overall survival was 53.8%. 7 patients (14%) were alive beyond 5 years.

    Conclusion
    Hemithoracic radiotherapy can be safely delivered in selected patients following EPP. Although associated with significant early toxicity, most patients complete treatment and late toxicity is uncommon. Our outcomes compare favourably with recently-published international series.