New drugs and new toxicities: pembrolizumab-induced myocarditis

Area of Science:

• Oncology
• Cardiology
• Immunology

Background:

• Immune checkpoint inhibitors like pembrolizumab offer significant benefits in treating solid organ malignancies.
• However, these therapies are associated with a range of potential adverse reactions.
• Understanding these side effects is crucial for patient safety and effective treatment.

Observation:

• A patient with metastatic non-small-cell lung cancer developed dyspnea and cardiac dysfunction after two cycles of pembrolizumab.
• Diagnostic workup revealed ST-segment elevations and severe biventricular dysfunction, leading to a diagnosis of pembrolizumab-induced myocarditis.
• Other potential causes of cardiac dysfunction were systematically excluded.

Findings:

• The patient received corticosteroids and standard heart failure therapy.
• A significant clinical improvement and resolution of heart failure symptoms were observed following treatment.
• This case highlights the potential for programmed death receptor-1 (PD-1) inhibition to induce autoimmune myocarditis.

Implications:

• Pembrolizumab-associated myocarditis is a critical adverse event that requires prompt recognition and management.
• This case underscores the importance of monitoring for cardiac dysfunction in patients receiving PD-1 inhibitors.
• Clinicians should maintain a high index of suspicion for immune-related adverse events, including myocarditis, during pembrolizumab therapy.