EGFR FISH Performance in Japanese NSCLC Patients Matches Caucasian Performance

Strategic Insights -

A study conducted by investigators in the United States aimed to verify the performance of EGFR fluorescence in situ hybridization (FISH) in Japanese non-small-cell lung cancer (NSCLC) patients. The researchers enrolled a cohort of 44 Japanese patients with recurrent NSCLC after surgery and treated them with gefitinib 250 mg daily. The results showed that 29 tumors (66%) were EGFR FISH+ and 23 (53%) were HER2 FISH+, with an overall response rate of 52%. The study also found a significant association between EGFR FISH+ and HER2 FISH+ and the presence of EGFR mutation.

Key Takeaways:

  • The study included 44 Japanese patients with recurrent NSCLC after surgery, with 48% females and 52% never-smokers.
  • Adenocarcinoma was the most common histology (86%), and 73% had prior chemotherapy and 57% had stage III-IV at the time of surgery.
  • FISH was performed using the EGFR/Chromosome Enumeration Probe 7 and PathVysion DNA probes (Abbott Molecular), and specimens were classified as FISH positive if they showed gene amplification or high polysomy.
  • The overall response rate was 52%, with 65% of EGFR FISH+ patients and 29% of EGFR FISH- patients showing a response to gefitinib.
  • Survival was not impacted by the EGFR FISH or HER2 FISH status.
  • EGFR FISH+ was significantly associated with HER2 FISH+ and presence of EGFR mutation.

Statistics:

  • 44 Japanese patients with recurrent NSCLC after surgery were enrolled in the study.
  • 29 tumors (66%) were EGFR FISH+ and 23 (53%) were HER2 FISH+.
  • Overall response rate to gefitinib was 52%.
  • 65% of EGFR FISH+ patients showed a response to gefitinib, compared to 29% of EGFR FISH- patients.

Sources:

  • Varellagarcia et al. "EGFR and HER2 Genomic Gain in Recurrent Non-small Cell Lung Cancer After Surgery Impact on Outcome to Treatment with Gefitinib and Association with EGFR and KRAS Mutations in a Japanese Cohort." Journal of Thoracic Oncology, 2009;4(3):318-325.
  • Cancer Weekly, 2009.