Risk factor of pneumonitis on dose-volume relationship for chemoradiotherapy with durvalumab: Multi-institutional research in Japan

Comparison of post-chemoradiotherapy pneumonitis between Asian and non-Asian patients with locally advanced non-small cell lung cancer: a systematic review and meta-analysis

Background

Pneumonitis is a common complication for patients with locally advanced non-small cell lung cancer undergoing definitive chemoradiotherapy (CRT). It remains unclear whether there is ethnic difference in the incidence of post-CRT pneumonitis.

Methods

PubMed, Embase, Cochrane Library, and Web of Science were searched for eligible studies from January 1, 2000 to April 30, 2023. The outcomes of interest were incidence rates of pneumonitis. The random-effect model was used for statistical analysis. This meta-analysis was registered with PROSPERO (CRD42023416490).

Findings

A total of 248 studies involving 28,267 patients were included. Among studies of CRT without immunotherapy, the pooled rates of pneumonitis for Asian patients were significantly higher than that for non-Asian patients (all grade: 66.8%, 95% CI: 59.2%-73.9% vs. 28.1%, 95% CI: 20.4%-36.4%; P < 0.0001; grade ≥2: 25.1%, 95% CI: 22.9%-27.3% vs. 14.9%, 95% CI: 12.0%-18.0%; P < 0.0001; grade ≥3: 6.5%, 95% CI: 5.6%-7.3% vs. 4.6%, 95% CI: 3.4%-5.9%; P = 0.015; grade 5: 0.6%, 95% CI: 0.3%-0.9% vs. 0.1%, 95% CI: 0.0%-0.2%; P < 0.0001). Regarding studies of CRT plus immunotherapy, Asian patients had higher rates of all-grade (74.8%, 95% CI: 63.7%-84.5% vs. 34.3%, 95% CI: 28.7%-40.2%; P < 0.0001) and grade ≥2 (34.0%, 95% CI: 30.7%-37.3% vs. 24.6%, 95% CI: 19.9%-29.3%; P = 0.001) pneumonitis than non-Asian patients, but with no significant differences in the rates of grade ≥3 and grade 5 pneumonitis. Results from subgroup analyses were generally similar to that from the all studies. In addition, the pooled median/mean of lung volume receiving ≥20 Gy and mean lung dose were relatively low in Asian studies compared to that in non-Asian studies.

Interpretation

Asian patients are likely to have a higher incidence of pneumonitis than non-Asian patients, which appears to be due to the poor tolerance of lung to radiation. Nevertheless, these findings are based on observational studies and with significant heterogeneity, and need to be validated in future large prospective studies focusing on the subject.

Funding

None.

Exploratory analysis to predict pneumonitis during durvalumab consolidation therapy for patients with locally advanced non-small cell lung cancer from proteomic profiling of circulating extracellular vesicles

BACKGROUND

Risk factors for predicting pneumonitis during durvalumab consolidation after chemoradiotherapy (CRT) in locally advanced non-small cell lung cancer (LA-NSCLC) are still lacking. Extracellular vesicles (EVs) play a crucial role in intercellular communication and are potential diagnostic tools for various diseases.

METHODS

We retrospectively collected predurvalumab treatment serum samples from patients treated with durvalumab for LA-NSCLC, isolated EVs using anti-CD9 and anti-CD63 antibodies, and performed proteomic analyses. We examined EV proteins that could predict the development of symptomatic pneumonitis (SP) during durvalumab treatment. Potential EV-protein biomarkers were validated in an independent cohort.

RESULTS

In the discovery cohort, 73 patients were included, 49 with asymptomatic pneumonitis (AP) and 24 with SP. Of the 5797 proteins detected in circulating EVs, 33 were significantly elevated (fold change [FC] > 1.5, p < 0.05) in the SP group, indicating enrichment of the nuclear factor kappa B (NF-κB) pathway. Patients with high levels of EV-RELA, an NF-κB subunit, had a higher incidence of SP than those with low levels of EV-RELA (53.8% vs. 13.4%, p = 0.0017). In the receiver operating characteristic analysis, EV-RELA demonstrated a higher area under the curve (AUC) than lung V20 (0.76 vs. 0.62) and was identified as an independent risk factor in the multivariate logistic regression analysis (p = 0.008, odds ratio 7.72). Moreover, high EV-RELA was also a predictor of SP in the validation cohort comprising 43 patients (AUC of 0.80).

CONCLUSIONS

Circulating EV-RELA may be a predictive marker for symptomatic pneumonitis in patients with LA-NSCLC treated with durvalumab.

Analysis of clinical and physical dosimetric factors that determine the outcome of severe acute radiation pneumonitis in lung cancer patients

OBJECTIVE

We conducted a retrospective statistical analysis of clinical and physical dosimetric factors of lung cancer patients who had previously undergone lung and/or mediastinal radiotherapy and died of or survived severe acute radiation pneumonitis (SARP). Our study was the first to reveal the heterogeneity in clinical factors, physical dosimetric factors, and SARP onset time that determined the clinical outcomes of lung cancer patients who developed SARP.

MATERIALS AND METHODS

The clinical characteristics, physical dosimetry factors, and SARP onset time of deceased and surviving patients were retrospectively analyzed. SPSS 20.0 was used for data analysis. Student's t-test was used for intergroup comparison, and a Mann-Whitney U test was used for data with skewed distribution. Qualitative data were represented using frequencies (%), and Fisher's exact test or χ2 test was used for intergroup comparison of nonparametric data. Binary logistic analysis was used for univariate and multivariate analyses. Differences with a P < 0.05 were considered statistically significant.

RESULTS

Univariate analysis revealed that the potential predictors of SARP death were as follows: ipsilateral lung V5 and V30, contralateral lung V5, V10, and V30, total lung V5, V10, and V30, mean lung dose, mean heart dose, and maximum spinal cord dose. Multivariate analysis showed that ipsilateral lung V5 and total lung V5 were predictors that determined the final outcome of SARP patients. In addition, we analyzed the time from the completion of radiotherapy to SARP onset, and found significant difference between the two groups.

CONCLUSIONS

There was no decisive correlation between clinical characteristics and SARP outcome (i.e., death or survival) in lung radiotherapy patients. Ipsilateral lung V5 and total lung V5 were independent predictors of death in SARP patients.

Subpleural fibrotic interstitial lung abnormalities are implicated in non-small cell lung cancer radiotherapy outcomes

BACKGROUND

The relationship between interstitial lung abnormalities (ILAs) and the outcomes of lung cancer radiotherapy is unclear. This study investigated whether specific ILA subtypes are risk factors for radiation pneumonitis (RP).

PATIENTS AND METHODS

This retrospective study analysed patients with non-small cell lung cancer treated with radical-intent or salvage radiotherapy. Patients were categorised into normal (no abnormalities), ILA, and interstitial lung disease (ILD) groups. The ILA group was further subclassified into non-subpleural (NS), subpleural non-fibrotic (SNF), and subpleural fibrotic (SF) types. The Kaplan-Meier and Cox regression methods were used to determine RP and survival rates and compare these outcomes between groups, respectively.

RESULTS

Overall, 175 patients (normal, n = 105; ILA-NS, n = 5; ILA-SNF, n = 28; ILA-SF, n = 31; ILD, n = 6) were enrolled. Grade ≥2 RP was observed in 71 (41%) patients. ILAs (hazard ratio [HR]: 2.33, p = 0.008), intensity-modulated radiotherapy (HR: 0.38, p = 0.03), and lung volume receiving 20 Gy (HR: 54.8, p = 0.03) contributed to the cumulative incidence of RP. Eight patients with grade 5 RP were in the ILA group, seven of whom had ILA-SF. Among radically treated patients, the ILA group had worse 2-year overall survival (OS) than the normal group (35.3% vs 54.6%, p = 0.005). Multivariate analysis revealed that the ILA-SF group contributed to poor OS (HR: 3.07, p =0.02).

CONCLUSIONS

ILAs, particularly ILA-SF, may be important risk factors for RP, which can worsen prognosis. These findings may aid in making decisions regarding radiotherapy.

Dosimetric predictors of pneumonitis in locally advanced non-small cell lung cancer patients treated with chemoradiation followed by durvalumab

OBJECTIVES

The incidence and predictors of pneumonitis for patients with unresectable, locally advanced non-small cell lung cancer (NSCLC) in the era of consolidation durvalumab have yet to be fully elucidated. In this large single institution analysis, we report the incidence of and factors associated with grade 2 + pneumonitis in NSCLC patients treated with the PACIFIC regimen.

MATERIALS AND METHODS

We identified all patients treated at our institution with definitive CRT followed by durvalumab from 2018 to 2021. Clinical documentation and imaging studies were reviewed to determine grade 2 + pneumonitis events, which required the following: 1) pulmonary symptoms warranting prolonged steroid taper, oxygen dependence, and/or hospital admission and 2) radiographic findings consistent with pneumonitis.

RESULTS

One-hundred ninety patients were included. The majority received 60 Gray (Gy) in 30 fractions with concurrent carboplatin and paclitaxel. Median number of durvalumab cycles received was 12 (IQR: 4-22). At a median follow-up of 14.8 months, 50 (26.3%) patients experienced grade 2 + pneumonitis with a 1-year cumulative incidence of 27.8% (95% CI: 21.9-35.4). Seventeen (8.9%) patients experienced grade 3 + pneumonitis and 4 grade 5 (2.1%). Dosimetric predictors of pneumonitis included ipsilateral and total lung volume receiving 5 Gy or greater (V5Gy), V10Gy, V20Gy, V40Gy, and mean dose and contralateral V40Gy. Heart V5Gy, V10Gy, and mean dose were also significant variables. Overall survival estimates at 1 and 3 years were 87.4% (95% CI: 82.4-92.8) and 60.3% (95% CI: 47.9-74.4), respectively.

CONCLUSION

We report a risk of pneumonitis higher than that seen on RTOG 0617 and comparable to the PACIFIC study. Multiple lung and heart dosimetric factors were predictive of pneumonitis.

Radiotherapy Patterns of Care for Locally-advanced Non-small Cell Lung Cancer in the Pre- and Post-durvalumab Era: A Region-wide Survey in a Japanese Prefecture

The promising results of the PACIFIC study led to the approval of consolidation durvalumab for coverage by the National Health Insurance (NHI) in 2018 for patients with locally-advanced unresectable non-small cell lung carcinoma (NSCLC) treated with definitive concurrent chemoradiotherapy (CCRT). However, the effect of NHI coverage on the patterns of care for this population remains unclear. Here, we conducted a questionnaire-based survey to determine the patterns of care for patients with stage II-III NSCLC treated with definitive radiotherapy in 2017 (pre-durvalumab era) or in 2019 (post-durvalumab era). Data were obtained from 11 radiotherapy facilities in Gunma prefecture, which has a population of 1.94 million. We identified 80 and 83 patients with stage II-III NSCLC who received definitive radiotherapy in Gunma in 2017 and 2019, respectively. At a given facility, CCRT was the treatment of choice in a significantly greater proportion of patients in 2019 than in 2017 (66% ± 20% vs 51% ± 29%, P = 0.041). Intensity-modulated radiotherapy (IMRT) was more frequent in 2019 than in 2017 (24% vs 1.2%). Carboplatin plus paclitaxel was used for CCRT at higher rate in 2019 than in 2017 (73% vs 44%). Consolidation durvalumab was performed in 73% (40/55) of CCRT-treated patients in 2019, and the treatment was performed for the planned 12 months in 45% (18/40) of patients. These data indicate that NHI coverage of durvalumab might be a possible reason for choosing CCRT in patients with stage II-III NSCLC in the real-world setting.

Risk factors for radiation pneumonitis after rotating gantry intensity-modulated radiation therapy for lung cancer

The risk factors for severe radiation pneumonitis (RP) in patients with lung cancer who undergo rotating gantry intensity-modulated radiation therapy (IMRT) using volumetric modulated arc therapy (VMAT) or helical tomotherapy (HT) are poorly understood. Fifty-two patients who received rotating gantry IMRT for locally advanced lung cancer were included in this retrospective study. In total, 31 and 21 patients received VMAT and HT, respectively. The median follow-up duration was 14 months (range, 5.2–33.6). Twenty (38%) and eight (15%) patients developed grade ≥ 2 and ≥ 3 RP, respectively. In multivariate analysis, lung V5 ≥ 40% was associated with grade ≥ 2 RP (P = 0.02), and past medical history of pneumonectomy and total lung volume ≤ 3260 cc were independently associated with grade ≥ 3 RP (P = 0.02 and P = 0.03, respectively). Rotating gantry IMRT was feasible and safe in patients with lung cancer undergoing definitive radiotherapy. Reducing lung V5 may decrease the risk of symptomatic RP, and care should be taken to avoid severe RP after radiotherapy in patients with a past medical history of pneumonectomy and small total lung volume.