Abstract Introduction Durvalumab is standard treatment for advanced or metastatic non-small cell lung cancers (NSCLC), adjunct with chemoradiation therapy (CRT). Pneumonitis is known to be an adverse effect of durvalumab. It poses significant diagnostic challenges to differentiate it from radiation-induced pneumonitis due to overlapping presentations. Here, we present a complex case of durvalumab-associated pneumonitis in a patient who received CRT for NSCLC. Case The patient is a 68-year-old female with a history of COPD on 4 L oxygen at baseline and tobacco use, who presented to the hospital with shortness of breath for the past few months. Her oxygen requirement had increased to 15 L from baseline. She has a history of stage III lung adenocarcinoma and had completed chemoradiation followed by immunotherapy with durvalumab, with the last dose administered less than a month ago. CT scan showed left upper lobe pulmonary fibrosis and a small left pleural effusion, which were new findings not seen on the scan six months ago (figure 1). A recent echocardiogram showed an EF of 54% and grade 2 diastolic dysfunction. The patient’s BNP was 66 on admission, and she was not clinically volume overloaded. She was admitted inpatient, durvalumab was held, and she was started on IV methylprednisolone. Her breathing improved over time. She was discharged home on prednisone 60 mg and 6 L oxygen with exercise. Discussion Pneumonitis is a serious and potentially fatal adverse event of durvalumab, leading to 2.1% of grade 5 pneumonitis and a 13% in-hospital death rate. The PACIFIC trial showed pneumonitis of any grade occurred in 33.9% of durvalumab patients, with grade 3 or 4 pneumonitis/radiation pneumonitis in 3.4% of patients. In our patient, the pneumonitis could have resulted from either radiation therapy, immunotherapy or combination of both. Labs showed a normal leukocyte count, no significant abnormalities in BMP or VBG, and a procalcitonin of 0.05, which helped exclude infectious causes of worsening lung lesions. She did not have signs or symptoms of heart failure exacerbation. The patient’s breathing significantly improved after receiving steroids, which suggests immune-induced pneumonitis. Moreover, she did not have any definite consolidative lesions within the radiation field to indicate radiation injury. Conclusion Accurate diagnosis of pneumonitis in a patient who received CRT is critical, as management differs between durvalumab-associated pneumonitis and radiation pneumonitis. Careful clinical history-taking, evaluation of lesion pattern, timing, and exclusion of infection are vital to make an accurate diagnosis. This abstract is funded by: None
Akter et al. (Fri,) studied this question.