Life threatening pembrolizumabinduced myositis in a patient treated for advanced adenocarcinoma of the lung.

The advent of immunotherapy in oncology has led to the emergence of a new spectrum of adverse effects. A number of these have the potential to contribute to life-threatening outcomes; and therefore require prompt identification and aggressive treatment to optimise management. In this report, we describe a case of pembrolizumab-induced CTCAE (common toxicity criteria for adverse events) grade 4 myositis in a non-small cell lung cancer patient.