Non-small-cell lung cancer with ERBB2 mutation in non-tyrosine kinase domain benefits from pyrotinib: A case report

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Exon 20 insertion mutations in the tyrosine kinase domain (TKD) of ERBB2 (HER2) are known drivers in non-small cell lung cancer (NSCLC).
• The clinical relevance of ERBB2 mutations outside the TKD in NSCLC remains largely unexplored.
• Current tyrosine kinase inhibitor (TKI) therapies have not shown efficacy in NSCLC patients with non-TKD ERBB2 mutations.

Observation:

• A patient with advanced lung adenocarcinoma was identified with a non-TKD ERBB2 mutation (S335C) and no other actionable genomic alterations.
• The patient received first-line monotherapy with pyrotinib, a pan-HER inhibitor.
• The patient achieved a durable partial response and exhibited good tolerance to pyrotinib treatment.

Findings:

• This case report highlights a positive clinical response to pyrotinib in an NSCLC patient with a rare non-TKD ERBB2 mutation.
• Pyrotinib, a pan-HER inhibitor, demonstrated significant efficacy in this patient population.
• The observed response was durable and well-tolerated.

Implications:

• Pyrotinib may represent a novel and effective first-line treatment strategy for NSCLC patients harboring non-TKD ERBB2 mutations.
• This finding expands the potential therapeutic targets within the ERBB2 pathway in lung cancer.
• Further clinical investigation is warranted to validate pyrotinib's efficacy in this specific NSCLC subgroup.