Onset of takotsubo syndrome induced by osimertinib in a patient with lung adenocarcinoma.

The cardiotoxicity of osimertinib, an epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor, has been recently reported when treating EGFR mutation-positive non-small cell lung cancer. In this report, we describe a case of an 81-year-old female patient diagnosed with Takotsubo syndrome (TTS). TTS occurred despite the patient receiving osimertinib retreatment at reduced doses and having no history of cardiac or respiratory disease. The findings of this case suggest that clinicians should consider the possibility of TTS induced by osimertinib.