The treatment of thoracic tumors with ionizing radiation can cause radiation-induced lung injury (RILI), which includes radiation pneumonitis and radiation-induced pulmonary fibrosis. Preventing RILI is crucial for controlling tumor growth and improving quality of life. However, the serious adverse effects of traditional RILI treatment methods remain a major obstacle, necessitating the development of novel treatment options that are both safe and effective. This review summarizes the molecular mechanisms of RILI and explores novel treatment options, including natural compounds, gene therapy, nanomaterials, and mesenchymal stem cells. These recent experimental approaches show potential as effective prevention and treatment options for RILI in clinical practice.

Antibody-drug conjugates (ADCs) have demonstrated effectiveness in treating various cancers, particularly exhibiting specificity in targeting human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Recent advancements in phase 3 clinical trials have broadened current understanding of ADCs, especially trastuzumab deruxtecan, in treating other HER2-expressing malignancies. This expansion of knowledge has led to the US Food and Drug Administration\'s approval of trastuzumab deruxtecan for HER2-positive and HER2-low breast cancer, HER2-positive gastric cancer, and HER2-mutant nonsmall cell lung cancer. Concurrent with the increasing use of ADCs in oncology, there is growing concern among health care professionals regarding the rise in the incidence of interstitial lung disease or pneumonitis (ILD/p), which is associated with anti-HER2 ADC therapy. Studies on anti-HER2 ADCs have reported varying ILD/p mortality rates. Consequently, it is crucial to establish guidelines for the diagnosis and management of ILD/p in patients receiving anti-HER2 ADC therapy. To this end, a panel of Chinese experts was convened to formulate a strategic approach for the identification and management of ILD/p in patients treated with anti-HER2 ADC therapy. This report presents the expert panel\'s opinions and recommendations, which are intended to guide the management of ILD/p induced by anti-HER2 ADC therapy in clinical practice.

UNASSIGNED: To compare the prognostic differences between non-small cell lung cancer (NSCLC) patients with mild and severe checkpoint inhibitor-associated pneumonitis (CIP), and explore the causes of death and prognostic risk factors in NSCLC patients with severe CIP.
UNASSIGNED: A retrospective study of a cohort of 116 patients with unresectable stage III or IV NSCLC with any grade CIP from April 2016 to August 2022 were conducted. To analyze the clinical characteristics of patients with different CIP grades, patients were divided into mild CIP group (grade 1-2, n=49) and severe CIP group (grade 3-5, n=67) according to the grade of CIP. To explore the OS-related risk factors in the severe CIP group, the patients were divided into a good prognosis (GP) group (≥ median OS, n=30) and a poor prognosis (PP) group (< median OS, n=37) based on whether their overall survival (OS) were greater than median OS. Baseline clinical and laboratory data were collected for analysis.
UNASSIGNED: The median OS of all NSCLC patients combined with CIP was 11.4 months (95%CI, 8.070-16.100), The median OS for mild CIP and severe CIP was 22.1 months and 4.4 months respectively (HR=3.076, 95%CI, 1.904-4.970, P<0.0001). The results showed that the most common cause of death among severe CIP patients in the PP group was CIP and the most common cause in the GP group was tumor. The univariate regression analysis showed that suspension of antitumor therapy was a risk factor for poor prognosis (OR=3.598, 95%CI, 1.307-9.905, p=0.013). The multivariate logistic regression analysis showed that suspension of anti-tumor therapy (OR=4.24, 95%CI, 1.067-16.915, p=0.040) and elevated KL-6 (OR=1.002, 95%CI, 1.001-1.002, p<0.001) were independent risk factors for poor prognosis.
UNASSIGNED: In conclusion, patients with severe CIP had a poor prognosis, especially those with elevated KL-6, and the main cause of death is immune checkpoint inhibitor-associated pneumonitis complicated with infection. In addition, anti-tumor therapy for severe CIP patients should be resumed in time and should not be delayed for too long.

OBJECTIVE: To compare the risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors, the meta-analysis was designed.
METHODS: The difference in risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors was assessed by two different meta-analysis methods, the Mirror-pairing and the PRISMA guidelines.
RESULTS: A total of eighty-eight reports were used for meta-analysis, while thirty-two studies were used for the Mirror-pairing. Both PD-1 and PD-L1 inhibitors (used alone or combined with chemotherapy) increased the risk of developing immune-related pneumonitis (P < 0.00001; P < 0.00001). Based on indirect analyses results (subgroup analyses), the risk of PD-L1-induced pneumonitis was weaker than that of PD-1 inhibitors when the control group was chemotherapy (OR = 3.33 vs. 5.43) or placebo (OR = 2.53 vs. 3.19), while no obvious significant differences were found (P = 0.17; P = 0.53). For the Mirror-pairing-based meta-analysis, the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors (OR = 1.46, 95%CI [1.08, 1.98], I2 = 0%, Z = 2.47 (P = 0.01)). However, this difference was not significant, when they were combined with chemotherapy (OR = 1.05, 95%CI [0.68, 1.60], I2 = 38%, Z = 0.21 (P = 0.84)).
CONCLUSIONS: Both PD-1 and PD-L1 inhibitors increased the risk of immune-related pneumonitis, while the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors.

BACKGROUND: Previous studies involving risk-benefit analysis of trastuzumab deruxtecan (DS-8201) have indicated the benefit of this treatment, although it may increase the risk of interstitial lung disease (ILD) and/or pneumonitis in certain patients. This study aimed to assess the safety of DS-8201.
METHODS: A search was done for relevant articles in four electronic databases: PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov. All reports published up until November 2, 2022, were included, and study types were restricted to clinical trials; the last search was then updated to January 10, 2023. We also assessed the quality of the literature with the Cochrane Handbook for Systematic Reviews of Interventions and the Methodological Index for Non-Randomized Studies tool, and then performed a meta-analysis with R version 4.2.1.
RESULTS: A total of 1428 patients reported in 13 articles were included in this study. The analysis revealed that the most common all-grade treatment-emergent adverse events (TEAEs) were nausea and fatigue. The most common TEAE of grade 3 or above (grade ≥3) was neutropenia. The incidences of ILD and/or pneumonitis for all-grade and grade ≥3 TEAEs were 12.5% and 2.2%, respectively.
CONCLUSIONS: This comprehensive summary of the incidence of TEAEs associated with DS-8201 in clinical trials provides an important guide for clinicians. The most common TEAEs were gastrointestinal reactions and fatigue; meanwhile, the most common grade ≥3 TEAE was hematological toxicity. ILD and/or pneumonitis were specific adverse drug reactions associated with DS-8201, of which physicians should be particularly aware for their higher morbidity and rates of grade ≥3 TEAEs.

UNASSIGNED: Immune checkpoint inhibitors (ICIs) have shown high efficacy in lung cancer. Adding ICIs to chemoradiation might increase the treatment efficacy, while the application of ICIs or chemoradiation alone can induce treatment-related pneumonitis, so whether combination therapy would increase the risk of pneumonitis needs careful evaluation. This study aimed to retrospectively analyze the incidence of pneumonitis in patients who underwent chemoradiation combined with ICIs compared with chemoradiation alone and explore the risk factors of pneumonitis in combination therapy.
UNASSIGNED: This was a retrospective cohort study. Patients who received conventional thoracic radiation with a minimum total dose of 50 Gy for lung cancer between January 2020 and December 2021 at West China Hospital were retrospectively reviewed and followed up for at least 6 months after radiation. Patients were divided into two groups according to whether chemoradiation was administered with or without ICIs. Pneumonitis was evaluated by chest computed tomography (CT) at least every 2 months in outpatient department. The clinical characteristics, including sex, age, smoking history, pathological diagnosis, baseline pulmonary disease [including chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD)], treatment strategy, location of primary tumor and radiological dosimetric parameters were recorded. Chi-squared tests or Fisher\'s exact tests were performed to analyze the difference between the combination group and control group for categorical variables and Mann-Whitney U test for continuous variables. Univariate and multivariate analyses were performed by logistic regression.
UNASSIGNED: A total of 152 patients who received chemoradiation were enrolled. The median age was 59 years. A total of 115 (75.7%) patients were non-small cell lung cancer (NSCLC), 22 (14.5%) were small cell lung cancer (SCLC), and 15 (9.9%) were other pathological types. Among them, 58 received chemoradiation combined with ICIs and 94 received chemoradiation alone. The rate of grade ≥2 pneumonitis was significantly higher in the combination therapy group (39.7% vs. 22.3%, P=0.028) and was associated with the use of ICIs [odds ratio (OR): 2.641, 95% confidence interval (CI): 1.244-5.608, P=0.011] and percent volume of the lung receiving ≥30 Gy (V30) (OR: 1.728, 95% CI: 1.214-2.460, P=0.002). The history of chronic lung disease was the independent risk factor (OR: 6.359, 95% CI: 1.953-20.705, P=0.002) of grade ≥3 pneumonitis. In the combination group, univariate and multivariate analyses revealed that V5, V20, V30, and mean lung dose (MLD) were not associated with pneumonitis, whereas the history of chronic lung disease was an independent risk factor of grade ≥3 pneumonitis (OR: 8.351, 95% CI: 1.469-47.484, P=0.017).
UNASSIGNED: The incidence of pneumonitis of ICIs combined with chemoradiation was higher than chemoradiation alone, but manageable. The combination therapy should be applied with caution especially in patients with history of chronic lung disease.

OBJECTIVE: Chemoradiotherapy (CRT) combined with immune checkpoint inhibitors (ICIs) is the standard of care for patients with unresectable and locally advanced non-small cell lung cancer. This study aimed to determine whether the addition of ICIs to CRT is associated with an increased risk of pneumonitis.
METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible studies published between January 1, 2015, and July 31, 2023. The outcome of interest was the incidence rate of pneumonitis. A random-effects model was used for statistical analysis.
RESULTS: A total of 185 studies with 24,527 patients were included. The pooled rate of grade ≥2 pneumonitis for CRT plus ICIs was significantly higher than that for CRT alone (29.6%; 95% CI, 25.7%-33.6% vs 20.2%; 95% CI, 17.7%-22.8%; P < .0001) but not that of grade ≥3 (5.7%; 95% CI, 4.8%-6.6% vs 5.6%; 95% CI, 4.7%-6.5%; P = .64) or grade 5 (0.1%; 95% CI, 0.0%-0.2% vs 0.3%; 95% CI, 0.1%-0.4%; P = .68). The results from the subgroup analyses of prospective studies, retrospective studies, Asian and non-Asian studies, concurrent CRT (cCRT), and durvalumab consolidation were comparable to the overall results. However, CRT or cCRT plus PD-1 inhibitors not only significantly increased the incidence of grade ≥2 but also that of grade ≥3 pneumonitis compared to CRT alone or cCRT plus PD-L1 inhibitors.
CONCLUSIONS: Compared with CRT alone, durvalumab consolidation after CRT appears to be associated with a higher incidence of moderate pneumonitis and CRT plus PD-1 inhibitors with an increased risk of severe pneumonitis. Nevertheless, these findings are based on observational studies and need to be validated in future large head-to-head studies.

The combination of thoracic radiotherapy and immune checkpoint inhibitors (ICIs) has emerged as a novel treatment approach for malignant tumors. However, it is important to consider the potential exacerbation of lung injury associated with this treatment modality. The neutrophil-to-lymphocyte ratio (NLR), an inflammatory marker, holds promise as a non-invasive indicator for assessing the toxicity of this combination therapy. To investigate this further, a study involving 80 patients who underwent thoracic radiotherapy in conjunction with ICIs was conducted. These patients were divided into two groups: The concurrent therapy group and the sequential therapy group. A logistic regression analysis was conducted to ascertain risk factors for grade ≥2 pneumonitis. Following propensity score matching, the NLR values were examined between the concurrent group and the sequential group to evaluate any disparity. A mouse model of radiation pneumonitis was established, and ICIs were administered at varying time points. The morphological evaluation of lung injury was conducted using H&E staining, while the NLR values of peripheral blood were detected through flow cytometry. Logistic regression analysis revealed that radiation dosimetric parameters (mean lung dose, total dose and V20), the inflammatory index NLR at the onset of pneumonitis, and treatment sequences (concurrent or sequential) were identified as independent predictors of grade ≥2 treatment-related pneumonitis. The results of the morphological evaluation indicated that the severity of lung tissue injury was greater in cases where programmed cell death protein 1 (PD-1) blockade was administered during thoracic radiotherapy, compared with cases where PD-1 blockade was administered 14 days after radiotherapy. Moreover, the present study demonstrated that the non-invasive indicator known as the NLR has the potential to accurately reflect the aforementioned injury.

Anticancer drug-induced interstitial lung disease (DIILD) has received increasing clinical attention, and the quality of relevant guidance documents has become critical. Our purpose was to assess the quality of documents for anticancer DIILD and summarize the recommendations. Clinical practice guidelines (CPGs) and consensus statements with recommendations were searched in electronic databases, websites of guideline organizations, and professional societies. The quality of documents was assessed using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) methodology, and the specific recommendations were aggregated and compared. A total of 11 documents were eligible, including 6 CPGs and 5 consensus statements, and the quality of AGREE II assessments differed greatly. The domains of scope and purpose and clarity of presentation received the highest median scores, while the stakeholder involvement domain received the lowest score. Recommendations were inconsistent between documents, particularly regarding the selection of steroid regimens. The methodological quality of the guidance documents needs to be enhanced, especially in the domain of stakeholder involvement. Inconsistencies exist in documents, and further discussions among multidisciplinary experts are needed. Particularly, differences in steroid regimens require attentions, and researches on the risks of adverse events and discovery of precise biomarkers are necessary.

With the widespread use of immune checkpoint inhibitors to treat various cancers, pulmonary toxicity has become a topic of increasing concern. Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibodies are strongly associated with rapidly progressive interstitial lung disease (RP-ILD) in patients with clinically amyopathic dermatomyositis. However, anti-MDA5 antibody expression has not been reported in patients with immune-related adverse events. We present the case of a 74-year-old man with lung adenocarcinoma who developed RP-ILD after treatment with immune checkpoint inhibitors. Further investigation revealed multiple autoantibodies, including anti-MDA5 antibodies. He initially responded to systemic glucocorticoids, immunosuppressants, and tocilizumab but eventually died from worsening pneumomediastinum. This case is the first one to suggest that checkpoint inhibitor pneumonitis can present as RP-ILD with positive anti-MDA5 antibodies, which may be predictive of a poor prognosis.