Author of

• 16637

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  P1.03 - Poster Session with Presenters Present (ID 455)

  • Event: WCLC 2016
  • Type: Poster Presenters Present
  • Track: Radiology/Staging/Screening
  • Presentations: 1
  • Moderators:
  • Coordinates: 12/05/2016, 14:30 - 15:45, Hall B (Poster Area)

  • 16656

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    P1.03-019 - Imaging of Anti-PD1 Therapy Response in Advanced Non-Small Lung Cancer (ID 6316)

    14:30 - 14:30  |  Author(s): M. Hammer
    • Abstract

    Background:
    Therapy with immune checkpoint inhibitors can lead to unconventional tumor responses and autoimmune-mediated adverse effects resulting from immune activation. Here we sought to determine pseudo-progression and radiologically-evident anti-PD1 therapy mediated adverse events in routine clinical management in the advanced non-small cell lung cancer (NSCLC) population.
    
    Methods:
    A retrospective study was conducted of all adult NSCLC patients treated with anti-PD1 agents at our institution. Electronic medical records were reviewed to determine clinical assessment of anti-PD1 therapy response and imaging reports at restaging. Patients that did not have available follow-up imaging or clinical data while on anti-PD1-therapy were excluded from the study. Patient imaging exams with clinically suspected tumor pseudo-progression at 1[st] re-staging were analyzed to determine if subsequent imaging demonstrated pseudo-progression or true progression. The incidence of radiographically-evident adverse events attributed to anti-PD1 therapy by the oncologist were noted.
    
    Results:
    A total of 228 patients were started on anti-PD1 therapy at our institution, of which a total of 166 were evaluable. Of the evaluable patients, 80% of those received nivolumab and the remaining 20% received pembrolizumab. The overall response rate (complete response + partial response) was 23% at 1[st] restaging. Of these patients, 22 patients were suspected of pseudo-progression due to tumor enlargement and/or development of new lesions during the 1[st] 4-6 weeks of therapy and were maintained on anti-PD1 therapy. Of these patients, there were 5 confirmed cases of pseudo-progression at subsequent restaging. Radiologically-evident adverse events occurred in less than 5% of the population, primarily manifesting as pneumonitis.
    
    Conclusion:
    Pseudo-progression and radiographically-evident adverse events are important but uncommon occurrences in the setting of anti-PD1 therapy for advanced NSCLC.