A Case of Small Cell Lung Cancer with COVID-19 Pneumonia During Chemoimmunotherapy

Background. Many patients have contracted coronavirus infectious disease, emerged in 2019 (COVID-19) during lung cancer treatment. However, few reports of COVID-19 infection occurring during chemoimmunotherapy have been published. Case. The patient was a 50-year-old man with advanced small cell lung cancer who was undergoing chemoimmunotherapy. He presented with fever, anorexia, and contracted COVID-19, which led to pneumonia. Patients with lung cancer may be at increased risk for COVID-19 infection, which could worsen their prognosis. However, the patient's COVID-19 pneumonia improved with dexamethasone, and he was able to resume lung cancer treatment. Conclusion. Chemoimmunotherapy may lead to the development of severe disease in patients with COVID-19. COVID-19 pneumonia is often difficult to differentiate from lung injury caused by immune-related adverse events associated with chemoimmunotherapy. Upon the development of pneumonia, we should always suspect COVID-19, diagnose it early, and treat it appropriately. Furthermore, we need to carefully consider the resumption of lung cancer treatment after COVID-19, depending on the severity of residual fibrosis. © 2023 The Japan Lung Cancer Society.