Coexistence of three EGFR mutations in an NSCLC patient: A brief report

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• Epidermal growth factor receptor (EGFR) is a key target for tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC).
• EGFR mutations are crucial for targeted therapy in NSCLC patients.
• Multiple EGFR mutations on the same allele are challenging to detect and analyze.

Purpose of the Study:

• To investigate the presence of EGFR gene mutations in an advanced NSCLC patient.
• To analyze complex EGFR mutation patterns, including multiple mutations on a single allele.
• To evaluate the clinical implications of complex EGFR mutations in NSCLC.

Main Methods:

• Sanger sequencing and Ion Torrent sequencing were employed to detect EGFR mutations in tumor tissue.
• Sanger sequencing was used to analyze EGFR mutations in peripheral blood lymphocytes.
• Clinical data and treatment response were assessed for the NSCLC patient.

Main Results:

• Three coexisting mutations in the EGFR gene were identified in the NSCLC patient.
• Two of the EGFR mutations were located on exon 21 and present on the same allele.
• The third EGFR mutation was found on exon 20, and the patient showed clinical benefit from afatinib treatment.

Conclusions:

• This case highlights an NSCLC patient with a rare pattern of three coexisting EGFR mutations, two on the same allele.
• Such complex mutation profiles may indicate a genetic predisposition to cancer in offspring.
• Future screening guidelines may benefit from improved risk calculation for lung cancer susceptibility, considering complex EGFR mutation patterns.