Discussion
Osimertinib is a third-generation oral EGFR tyrosine kinase inhibitor
(TKI) used for the treatment of advanced EGFR-mutant NSCLC with acquired
T790M mutations. It has also been shown to improve progression-free
survival compared to platinum therapy (7). Although cardiotoxicity from
EGFR-TKI (human EGFR1: HER1) has been reported to be less than that of
HER2, BCR-ABL, and VEGFR inhibitors (3), osimertinib is likely to cause
cardiac side effects (4-6).
TC is a transient systolic left ventricular dysfunction with a variety
of wall motion abnormalities (8). Elderly women and emotional or
physical triggers were considered to be the cause of TC, but conditions
without an evident trigger have also been reported (8,9). In a previous
study, EGFR was found to be expressed in the central nervous system, and
infusion of EGFR into the midbrain had increased dopamine precursor
levels in an experimental rat model. One of the mechanisms of
osimertinib-induced TC might be that osimertinib, may cross the
blood-brain barrier, increasing the dopamine release in the central
nervous system (10).
Osimertinib may cause TC, which has the possibility of cause of heart
failure. The findings of our case study suggest that osimertinib therapy
should not be resumed in patients diagnosed with symptomatic heart
failure due to TC induced by osimertinib.