Imaging of Oncologic Treatment-Related Pneumonitis: A Focused Review on Emerging Issues of Immune Checkpoint Inhibitor Pneumonitis, From the AJR Special Series on Inflammation

Drug-induced Lung Disease in the Oncology Patient: From Cytotoxic Agents to Immunotherapy

Drug-induced lung disease is commonly encountered, especially in the oncology setting. Diagnosis is challenging because clinical and radiologic findings are nonspecific, often overlapping with other lung pathologies in these patients due to underlying neoplasia, infection, or other treatment effects such as radiotherapy. Furthermore, oncology patients often receive multiple antineoplastic agents concurrently, and virtually every agent has an association with lung injury. In this article, we will review a variety of antineoplastic agents that are associated with drug-induced injury and discuss incidence, their typical timing of onset, and imaging features.

Immune checkpoint inhibitor-related chronic pneumonitis: a case report and literature review

Immune checkpoint inhibitor (ICI)-related chronic pneumonitis is rare. Limited information is available on the characteristics of this condition. Herein, we present the case of a 54-year-old man with recurrent severe ICI-related pneumonitis. The patient developed fever and dyspnea during both episodes of pneumonitis. He had been previously diagnosed with gastric signet ring cell carcinoma and was undergoing treatment with an anti-PD-1 combination chemotherapy regimen. We reviewed previous case reports of ICI-related pneumonitis according to the primary cancer, time of onset in relation to ICI therapy and chest imaging findings. ICI-related pneumonitis can progress to chronic pneumonitis. Repeated computed tomography imaging showing lung changes in the same location may help to make the diagnosis.

A rare case of double primary lung adenocarcinomas with uncommon complex EGFR G719X and S768I mutations and pleomorphic carcinoma

Epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI)-targeted therapy has emerged as a viable treatment for patients with advanced non-small cell lung cancer with common EGFR mutations. The uncommon G719X and S768I mutations can co-occur as complex mutations in the same tumor. Here we report a case of a 72-year-old male patient with double lung carcinoma, with G719X and S768I complex mutations detected in the right upper lung lobe along with brain metastases. Osimertinib (80 mg/day) was administered as the first-line treatment, and a reduction in the right lobe tumor and brain lesions was achieved. However, the left upper lung lobe mass remained unchanged; histopathological examination via a lobectomy revealed pleomorphic carcinoma. Thus, the patient was diagnosed with multiple primary lung cancers. In conclusion, osimertinib is a viable treatment option for lung cancer with rare EGFR G719X and S768I complex mutations.

Clinical applications of radiomics in non-small cell lung cancer patients with immune checkpoint inhibitor-related pneumonitis

Immune checkpoint inhibitors (ICIs) modulate the body's immune function to treat tumors but may also induce pneumonitis. Immune checkpoint inhibitor-related pneumonitis (ICIP) is a serious immune-related adverse event (irAE). Immunotherapy is currently approved as a first-line treatment for non-small cell lung cancer (NSCLC), and the incidence of ICIP in NSCLC patients can be as high as 5%-19% in clinical practice. ICIP can be severe enough to lead to the death of NSCLC patients, but there is a lack of a gold standard for the diagnosis of ICIP. Radiomics is a method that uses computational techniques to analyze medical images (e.g., CT, MRI, PET) and extract important features from them, which can be used to solve classification and regression problems in the clinic. Radiomics has been applied to predict and identify ICIP in NSCLC patients in the hope of transforming clinical qualitative problems into quantitative ones, thus improving the diagnosis and treatment of ICIP. In this review, we summarize the pathogenesis of ICIP and the process of radiomics feature extraction, review the clinical application of radiomics in ICIP of NSCLC patients, and discuss its future application prospects.

Features of post-obstructive pneumonia in advanced lung cancer patients, a large retrospective cohort

BACKGROUND

Post-obstructive pneumonia refers to an infection of the lung parenchyma distal to a bronchial obstruction. Previous experience-based studies reported a high prevalence of this infection among patients with a medical history of advanced lung neoplasia, up to 40-55%.

OBJECTIVES

The current study was designed to investigate the features of post-obstructive pneumonia in lung cancer, including its predictors and the discriminants for 30-day mortality.

METHOD

Data from medical records at the tertiary University centre, UZ Brussel, were collected retrospectively between January 2016 and January 2021. Patients affected by lung cancer stages III and IV were included. A multidisciplinary team, composed of a pulmonologist, an infectious disease specialist and a chest radiologist, identified patients affected by post-obstructive pneumonia.

RESULTS

A total of 408 patients were included, of which 46 (11%) were diagnosed with post-obstructive pneumonia. Multivariable logistic regression for predictors of disease onset found significant differences for squamous cell carcinoma (OR:2.46 p-value: .014) and hilar location of the tumour (OR:2.72 p-value: .021). However, no significant differences were identified with regards to age or comorbidities. Furthermore, 30-day mortality among post-obstructive pneumonia patients was 30%. Multivariable logistic regression for prediction of 30-day mortality found significant differences in CURB-65 score (OR:73.20 p-value: .001) and smoking status (OR:0.009 p-value: .015).

CONCLUSIONS

Within this cohort, the prevalence of post-obstructive pneumonia in advanced lung cancer patients was lower than previously reported. Squamous cell carcinoma and a hilar tumour location were two variables associated with disease development, independent of age and comorbidities. Furthermore, a higher CURB-65 score at post-obstructive pneumonia diagnosis was correlated with mortality.

GM, Sasidharan B, Thangakunam B, Pavamani S, Isiah R, Joel A, Bhat TA. Imaging Recommendations for Diagnosis, Staging, and Management of Lung Cancer

Globally and in India, lung cancer is one of the leading malignancies in terms of incidence and mortality. Smoking and environmental pollution are the common risk factors for developing lung cancer. Traditionally, lung cancer is divided into small cell and nonsmall cell types, with nonsmall cell carcinomas including squamous cell carcinoma, adenocarcinoma, and large cell carcinoma.

In this review article, we describe the imaging recommendations and findings in the diagnosis, staging, and management of lung cancer, including the imaging of treatment-related complications.

Imaging of Drug-Related Pneumonitis in Oncology

Clinical applications of novel anticancer agents in the past few decades brought marked advances in cancer treatment, enabling remarkable efficacy and effectiveness; however, these novel agents are also associated with toxicities. Among various toxicities, drug-related pneumonitis is one of the major clinical challenges in the management of cancer patients. Imaging plays a key role in detection, diagnosis, and monitoring of drug-related pneumonitis during cancer treatment. In the current era of precision oncology, pneumonitis from molecular targeted therapy and immune-checkpoint inhibitors (ICI) has been recognized as an event of clinical significance. Additionally, further advances of therapeutic approaches in cancer have brought several emerging issues in diagnosis and monitoring of pneumonitis. This article will describe the computed tomography (CT) pattern-based approach for drug-related pneumonitis that has been utilized to describe the imaging manifestations of pneumonitis from novel cancer therapies. Then, we will discuss pneumonitis from representative agents of precision cancer therapy, including mammalian target of rapamycin inhibitors, epidermal growth factor receptor inhibitors, and ICI, focusing on the incidence, risk factors, and the spectrum of CT patterns. Finally, the article will address emerging challenges in the diagnosis and monitoring of pneumonitis, including pneumonitis from combination ICI and radiation therapy and from antibody conjugate therapy, as well as the overlapping imaging features of drug-related pneumonitis and coronavirus disease 2019 pneumonia. The review is designed to provide a practical overview of drug-related pneumonitis from cutting-edge cancer therapy with emphasis on the role of imaging.