A Case of Successful Resumption of Tepotinib After COVID-19 Pneumonia in a Patient with Non-small Cell Lung Cancer Harboring a Mesenchymal-epithelial Transition Exon 14 Skipping Mutation

Background. Approximately 3-4% of patients with non-small cell lung cancer (NSCLC) exhibit a mesenchymal-epithelial transition (MET) exon 14 skipping mutations. Tepotinib has been approved for patients with locally advanced or metastatic NSCLC with MET exon 14 skipping mutations. Pulmonary fibrosis and fibrotic-like changes occur in 35-56% of COVID-19 patients after six months. Interstitial pneumonia, particularly pulmonary fibrosis, is a risk factor for lung injury during lung cancer treatment with chemotherapy. The safety of resuming tepotinib therapy after COVID-19 pneumonia has not been thoroughly examined. Case. A 75-year-old woman diagnosed with lung adenocarcinoma, cT2aN0M1b, stage IVA, harbored a MET exon 14 skipping mutation and was treated with tepotinib. Although the treatment was effective, she contracted COVID-19 two months later. Computed tomography revealed bilateral consolidation, and the patient was diagnosed with COVID-19 pneumonia. Tepotinib was discontinued because of COVID-19 pneumonia. Although some residual effects remained as ground-glass opacities, most of the bilateral consolidation, which was considered the result of COVID-19 pneumonia, had improved, so tepotinib treatment was resumed. Tepotinib administered after COVID-19 pneumonia did not cause a recurrence of lung damage or drug-induced pneumonia, and it was continued for nine months after resumption, with treatment continued for approximately one year in total. Conclusion. Tepotinib may be safely resumed even after COVID-19 pneumonia. It is considered an effective treatment for NSCLC harboring MET exon 14 skipping mutation, even after COVID-19 pneumonia.