Rare ashy dermatosis-like hyperpigmentation associated with osimertinib

Area of Science:

• Oncology
• Dermatology
• Pharmacology

Background:

• Osimertinib is a first-line treatment for EGFR-mutated non-small cell lung cancer.
• Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) can cause skin side effects.
• Pigmentary changes are uncommon adverse events associated with EGFR-TKIs.

Observation:

• A patient receiving osimertinib developed ashy dermatosis-like hyperpigmentation.
• This skin manifestation was observed on imaging.
• The hyperpigmentation did not resolve with a reduced osimertinib dose of 40 mg.

Findings:

• Osimertinib-associated hyperpigmentation is a rare adverse event.
• The presentation mimicked ashy dermatosis.
• Despite the skin changes, osimertinib was continued due to sustained clinical and radiological benefits.

Implications:

• Clinicians should be aware of rare skin toxicities like hyperpigmentation with osimertinib.
• Monitoring for dermatological side effects is important in patients treated with osimertinib.
• The benefits of osimertinib may outweigh rare adverse events, necessitating continued treatment in select cases.