Successful dabrafenib and trametinib combination therapy in a patient with recurrent BRAF V600E -mutant non-small-cell lung cancer and coexisting radiation pneumonitis.

There have been several reports of drug-induced lung injury caused by molecular-targeted agents. Additionally, medical history of interstitial lung disease and chest irradiation are established risk factors for the development and progression of drug-induced lung injury. Moreover, the presence of fibrosis on chest computed tomography before treatment is a predictive factor for the appearance of pneumonia induced by anticancer drugs. Accordingly, patients with a history of interstitial lung disease or pneumonitis were excluded from clinical trials of dabrafenib and trametinib combination therapy for patients with previously treated BRAF V600E -mutant metastatic non-small-cell lung cancer. This article presents a case of successful dabrafenib and trametinib combination therapy in a patient with BRAF V600E -mutant non-small-cell lung cancer who had a history of radiation pneumonitis and developed recurrence after conventional chemoradiotherapy.