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Epidemiological Characteristics, EGFR Status and Management Patterns of Advanced Non-small Cell Lung Cancer Patients:
Konstantinos N Syrigos1, Vasilis Georgoulias2, Konstantinos Zarogoulidis3
1Oncology Unit, 3rd Department of Medicine, Medical School, National & Kapodistrian University of Athens, Athens, Greece ksyrigos@med.uoa.gr.
Background/Aim:
Real-world evidence regarding the prevalence of epidermal growth factor receptor (EGFR) mutation-positive status (M+) and the clinicopathological characteristics associated with the presence of EGFR mutations in advanced non-small cell lung cancer (NSCLC) is scarce, especially among Caucasian populations. The present study aimed to bridge this gap, as well as to record treatment patterns and outcomes in routine-care settings.
Patients And Methods:
REASON (NCT01153399) was a prospective study of patients with stage IIIB/IV NSCLC and known EGFR mutation status. Clinicopathological, treatment characteristics and clinical outcomes were recorded and correlated with EGFR mutation testing results.
Results:
Of 575 enrolled patients, EGFR mutations were detected in 15.7% of them. Male gender (p=0.008) and smoking (p<0.001), but not adenocarcinoma, were associated with EGFR M+ status. In the EGFR M+ subpopulation (n=88), absence of bone and/or brain metastasis and presence of exon 19 EGFR M+ status at diagnosis were independently associated with longer progression-free survival (PFS) (p=0.011 and p=0.040, respectively).
Conclusion:
In our population, males and smokers had decreased odds of harboring an EGFR mutation, while adenocarcinoma histology was not a significant predictor of EGFR M+ status. EGFR M+ patients with bone and/or brain metastases at diagnosis or mutations other than exon 19 deletions were at increased risk for earlier disease progression.
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