Author of

• 11645

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  P2.08 - Poster Session 2 - Radiotherapy (ID 198)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Radiation Oncology + Radiotherapy
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 11665

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    P2.08-020 - Prognositc parameters for local and regional control in locally advanced NSCLC patients treated with concurrent chemo-radiotherapy (ID 2385)

    09:30 - 09:30  |  Author(s): C. Chen
    • Abstract

    Background
    Traditionally, the same radiotherapy dose is prescribed to the primary tumor (PT) and involved lymph nodes (LN) for locally advanced NSCLC patients, independent of volume and metabolic activity of each lesion. On the other hand, the PT and lesions with a high [18]F-FDG uptake are often believed to have a higher recurrence rate. The purpose of this study was therefore to find prognostic parameters for the lesion control probability in locally advanced NSCLC.

    Methods
    A total of 279 patients treated between 2007 and 2011 with 24×2.75Gy IMRT and concurrent daily low dose cisplatin were included in this retrospective analysis. Patients had a staging FDG-PET scan within 6 weeks prior the start of treatment. For follow-up, CT thorax was performed 4-6 weeks after treatment and at 3-monthly intervals chest x-ray or CT scans were made up to 2 years after CCRT. Medical records of the patients were retrospectively reviewed. The PT and/or LN progression were classified based on follow-up records and scans by two physicians. The volume of each separate lesion on the planning CT and their SUVmax from the pre-RT staging PET scan were then tested as prognostic factors for disease progression using Cox proportional hazard model with patient as random effect. Data were analyzed using R, package “coxme”.

    Results
    A total of 291 PTs (8 patients had no PT, 252 had 1 PT, 18 had 2 PTs, 1 had 3 PTs) and 627 LNs (59 patients without LN, 57 had 1 LN, 57 had 2 LNs and 106 had >=3 LNs involved) were analyzed. The majority (92%) of the patients had TNM stage III and 86% patients had ≥N2. At a median follow-up of 30 months (95%CI 27-35) and median OS of 25 months (95% CI 21-29), 47 PTs had progression and 14 LNs had progression, 38% patients had systemic relapse. The log(Vol), SUVmax and lesion type (TP vs. LN) were each significant (p<0.001) as prognostic factor for progression in the univariate cox regression. In the multivariate analysis, log(Vol) remains as a significant predictor (p<0.001) with a trend toward significance for lesion type (p=0.07) (Figure 1). Figure 1

    Conclusion
    Our regimen of 66 Gy in 24fx results in excellent local-regional control in locally advanced NSCLC patients. The PT yields a significantly higher risk of progression than LNs. A larger lesion volume and higher SUVmax were associated with an increased risk of progression.