Promising Response to Pyrotinib in Non-Small-Cell Lung Cancer with the Rare HER2 R456C Mutation: A Case Report

To the best of our knowledge, this study represents the first reported case demonstrating the promising efficacy of pyrotinib in HER2-altered NSCLC harboring the ra-re exon 12 R456C mutation. Heterogeneous alterations in the HER2 extracellular segment, such as R456C, may be targetable and could confer survival benefits with HER2-targeted inhibitors.