Author of

• 14490

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  P2.04 - Poster Session/ Biology, Pathology, and Molecular Testing (ID 234)

  • Event: WCLC 2015
  • Type: Poster
  • Track: Biology, Pathology, and Molecular Testing
  • Presentations: 1
  • Moderators:
  • Coordinates: 9/08/2015, 09:30 - 17:00, Exhibit Hall (Hall B+C)

  • 14511

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    P2.04-021 - Predictive Value of Initial Maximal Standardized Uptake Value of 18F-FDG PET/CT in Patients with Lung Adenocarcinoma Treated with Erlotinib (ID 899)

    09:30 - 09:30  |  Author(s): T. Kus
    • Abstract

    Background:
    Targeted therapies like erlotinib, afatinib, gefitinib, crizotinib and ceritinib were suggested to be used in the first line treatment of non-small cell lung cancer (NSCLC) according to EGFR mutation and EML-4/ALK fusion gene analysis. EGFR mutation rate is about 10% in NSCLC and Exon 9 deletion and Exon 21 L858R are indicators of a longer progression free survival (PFS). According to guidelines thyrosine kinase inhibitors can also be used as switch or maintenance therapy after progression first-line therapy independent of EGFR mutation. This retrospective analysis indicates the predictive value of initial PET-CT SUVmax. in patients treated with erlotinib.
    
    Methods:
    This retrospective study about erlotinib was performed on patients with diagnosis of lung adenocarcinoma, treated with erlotinib as first-line, switch or maintenance therapy and after progression of first line chemotherapy in Gaziantep University Hospital Department of Medical Oncology, between 2008 and 2014. Preatreatment PET-CT imagings in last six months were scanned and peak SUVmax values of primary mass or metastasis were noted. Mean SUVmax values was 10,8. Thus, patients stratified as SUVmax above 10,8 and SUV max below 10,8. Also patients were grouped as EGFR muation positive (+), negative(-), and unknown. PET-CT and CT were used for follow-up and 3 months PFS and 6 months PFS ratios were enlisted according to RECIST criteria.
    
    Results:
    50 patient enrolled to this study. 27 of patients had SUV max. value below 10.8. Three months PFS rate of these patient was 77.8% (p:0.020), while it was 43.5% in patients who have SUV max. above 10.8. Also these rates were 66.7% and 21.7% for 6 months PFS (p:0.020). Subgroup analysis according to EGFR mutation status showed that 3 months PFS rates were %75.0, 54.5%, 52.6% in EGFR (+), EGFR (-) and EGFR unknown group respectively (p:0,301). These rates were %50, 45.5%, 42.1% for 6 months PFS (p: 0,884). In subgroup analysis of EGFR (+) patients, 3 months PFS rate was %100 in patients who have SUVmax below 10,8 and %66,7 in patients who have SUVmax above 10,8. These rates were %100 and %33,3 for 6-months PFS.
    
    Conclusion:
    Erlotinib showed better PFS ratios in EGFR positive patients who have low SUVmax values. Also erlotinib is an available drug for EGFR negative and unknown patients in consequent treatment of lung adenocarcinoma. SUVmax could be a predictive value for response. Predictive value of SUVmax could effect treatment decisions with multicenter studies proving this effect.