An Unusual Case of Lorlatinib-Induced Pneumonitis: A Case Report

The discovery of tyrosine kinase oncogenic driver mutations, including anaplastic lymphoma kinase (ALK), has changed the face of non-small cell lung cancer (NSCLC) treatment. Whilst the development of tyrosine kinase inhibitors has improved survival, with their increasing use, it is important to be aware of the risks of rare yet serious adverse events, such as drug-induced pulmonary toxicity. Whilst little is known in regard to drug-induced pneumonitis in the setting of ALK inhibitors, such reactions carry a high morbidity and mortality rate, impacting greatly upon options for further treatment and management. We describe the case of a 73-year-old female with metastatic ALK-positive NSCLC who developed subacute dyspnoea 3 weeks after commencing lorlatinib. She was diagnosed with drug-induced pneumonitis, from which she recovered clinically following the cessation of her targeted therapy. Pneumonitis related to lorlatinib is a rare pulmonary toxicity, and early recognition and intervention is critical to reduce the associated risks of respiratory failure and death.