Author of

• 12736

  +

  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

  • 12748

    +

    P3.14-012 - Pathological complete response after platinum-based chemotherapy in malignant pleural mesothelioma (ID 3072)

    09:30 - 09:30  |  Author(s): B. McCaughan
    • Abstract

    Background
    Prior to the demonstration of the efficacy of cisplatin/pemetrexed chemotherapy, Malignant pleural mesothelioma (MPM) was previously considered a chemotherapy-resistant tumour. In order to assess the efficacy of chemotherapy in the pre-operative setting, we aimed to: (1) determine the radiological and pathological complete response (CR) rate; (2) evaluate any potential association between pathological CR and patient characteristics; and (3) assess if pathological CR is associated with a longer disease free survival (DFS) and overall survival (OS) in MPM patients.

    Methods
    A retrospective review of a prospectively collected database of MPM patients treated with induction chemotherapy followed by extrapleural pneumonectomy (EPP) at our institutions since 2003 were performed. Radiological response was determined by CT/PET scans while pathological response was assessed by examination of the EPP specimen. OS and DFS from the day of EPP was determined by the Kaplan Meier method and comparison was made by log rank test. Chi square tests were used to determine potential association between pathological CR and patient characteristics.

    Results
    Forty-two patients are included: median age 63 years; 81% male. Pathology was 91% epithelial and 9% biphasic subtype. A median of 3 cycles of induction chemotherapy was administered with either 67% cisplatin-based and 31% carboplatin-based treatment. The regimen in the remaining 2% of patients was unknown. All patients proceeded to EPP and 86% of patients received adjuvant radiotherapy. The median OS was 30.6 months (95% CI: 2.9 – 58.2 months), while the median DFS was 19.6 months (95% CI: 11.0 – 28.2 months). No-one achieved a radiological CR. Four patients (9.5%) had pathological CR and all were male (p=0.31) and had epithelial subtype (p=0.50). No association was found between pathological CR and the type of chemotherapy (cisplatin vs. carboplatin; p=0.76) or the number of cycles administered (≤3 vs. >3; p=0.64). Median OS was 30.6 months vs. median not reached (p=0.31), while median DFS was 19.4 vs. 36 months (p=0.34), for those without pathological CR and those with pathological CR respectively.

    Conclusion
    A 9.5% pathological CR rate was demonstrated after induction chemotherapy, indicative of chemo-sensitivity in a subgroup of MPM patients. There was a trend for longer OS and DFS in MPM patients achieving a pathological CR.