Prolonged Central Nervous System Response in a Patient With HER2 Mutant NSCLC Treated With First-Line Poziotinib

Abstract

We report about a patient with NSCLC with HER2 exon 20 insertion who had a deep central nervous system (CNS) response with first-line poziotinib. A 53-year-old never-smoker woman presented with right shoulder pain and cough. Imaging revealed a right upper lobe (RUL) pulmonary mass, multiple large destructive lytic bone lesions, and brain metastases. Core biopsy from the left acetabular lesion confirmed lung adenocarcinoma. Plasma cell-free DNA hybrid capture comprehensive genomic profiling (CGP) (Guardant Health, Redwood City, CA) revealed an ERBB2 (HER2) A775_G776insYVMA exon 20 insertion mutation with an allele frequency of 13.5% and TP53 C277F of 8.6%.