Prognostic Value of Preoperative N Subcategories in Patients with Stage IIIA N2 Non-Small Cell Lung Cancer.

Purpose To evaluate the preoperative risk factors in patients with pathologic IIIA N2 non-small cell lung cancer (NSCLC) who underwent upfront surgery and to evaluate the prognostic value of new N subcategories. Materials and Methods Patients with pathologic stage IIIA N2 NSCLC who underwent upfront surgery in a single tertiary center from January 2015 to April 2021 were retrospectively reviewed. Each patient's clinical N (cN) was assigned to one of six subcategories (cN0, cN1a, cN1b, cN2a1, cN2a2, and cN2b) based on recently proposed N descriptors. Cox regression analysis was used to identify the significant prognostic factors for recurrence-free survival (RFS) and overall survival (OS). Results A total of 366 patients (mean age ± SD, 62.0 years ± 10.1; 202 male patients [55%]) were analyzed. The recurrence rate was 55% (203 of 366 patients) over a median follow-up of 37.3 months. Multivariable analysis demonstrated that cN (hazard ratios [HRs] for cN1 and cN2b compared with cN0, 1.66 [95% CI: 1.11, 2.48] and 2.11 [95% CI: 1.32, 3.38], respectively) and maximum lymph node (LN) size at N1 station (≥12 mm; HR, 1.62 [95% CI: 1.15, 2.29]), in addition to clinical T category (HR, 1.51 [95% CI: 1.14, 1.99]), were independent prognostic factors for RFS. For OS, clinical N subcategories (cN1, cN2a2, and cN2b vs cN0; HRs, 1.91 [95% CI: 1.11, 3.27], 1.89 [95% CI: 1.13, 2.18], and 2.02 [95% CI: 1.07, 3.80], respectively) and LN size at N1 station (HR, 1.75 [95% CI: 1.12, 2.71]) were independent prognostic factors. For clinical N1, OS was further stratified according to LN size (log-rank test, P < .001). Conclusion Assessing the proposed N subcategories by reporting single versus multistation involvement of N2 disease and maximum size of metastatic LN, reflecting metastatic burden, at preoperative CT may offer useful prognostic information for planning optimal treatment strategies. Keywords: CT, Lung, Staging, Non-Small Cell Lung Cancer Supplemental material is available for this article. ©RSNA, 2024.

Optimal approach for diagnosing peripheral lung nodules by combining electromagnetic navigation bronchoscopy and radial probe endobronchial ultrasound.

INTRODUCTION: Electromagnetic navigation bronchoscopy (ENB) and radial probe endobronchial ultrasound (RP-EBUS) are essential bronchoscopic procedures for diagnosing peripheral lung lesions. Despite their individual advantages, the optimal circumstances for their combination remain uncertain. METHODS: This single-center retrospective study enrolled 473 patients with 529 pulmonary nodules who underwent ENB and/or RP-EBUS biopsies between December 2021 and December 2022. Diagnostic yield was calculated using strict, intermediate, and liberal definitions. In the strict definition, only malignant and specific benign lesions were deemed diagnostic at the time of the index procedure. The intermediate and liberal definitions included additional results from the follow-up period. RESULTS: The diagnostic yield of the strict definition was not statistically different among the three groups (ENB/Combination/RP-EBUS 63.8%/64.2%/62.6%, p = 0.944). However, the diagnostic yield was superior in the ENB + RP-EBUS group for nodules with a bronchus type II or III and a solid part <20 mm (odds ratio 1.96, 95% confidence interval 1.09-3.53, p = 0.02). In terms of complications, bleeding was significantly higher in the ENB + RP-EBUS group (ENB/Combination/RP-EBUS 3.7% /6.2/0.6%, p = 0.002), but no major adverse event was observed. CONCLUSION: The combination of ENB and RP-EBUS enhanced the diagnostic yield for nodules with bronchus type II or III and solid part <20 mm, despite a slightly elevated risk of bleeding. Careful patient selection based on nodule characteristics is important to benefit from this combined approach.

A prospective, open-label, randomized clinical trial to evaluate the efficacy and safety of remimazolam in patients undergoing EBUS-TBNA: REST trial design.

BACKGROUND: Remimazolam is safe and effective for moderate sedation during flexible bronchoscopy, but its safety and efficacy during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) remains undetermined. The REST trial (NCT06275594) will be a prospective randomized study of remimazolam in patients undergoing EBUS-TBNA with conscious sedation. The primary aim is to evaluate whether remimazolam is safe and effective for moderate sedation during EBUS-TBNA compared to real-world midazolam and on-label midazolam. METHODS: The REST trial will recruit 330 patients from four university hospitals with mediastinal lesions suspected of being lung cancer who are eligible for EBUS-TBNA under moderate sedation. The participants will be randomized into groups using remimazolam, real-world midazolam, and on-label midazolam (US prescribing information dosage) to perform EBUS-TBNA for procedural sedation. The primary endpoint will be procedural success using composite measures. DISCUSSION: The REST trial will prospectively evaluate the efficacy and safety of remimazolam during EBUS-TBNA under moderate sedation. It will provide information for optimizing sedation modalities and contribute to practical benefits in patients undergoing EBUS-TBNA. TRIAL REGISTRATION: ClinicalTrials.gov (NCT06275594). Prospectively registered on 15 February 2024.

Safety and efficacy of SNK01 (autologous natural killer cells) in combination with cytotoxic chemotherapy and/or cetuximab after failure of prior tyrosine kinase inhibitor in non-small cell lung cancer: non-clinical mouse model and phase I/IIa clinical study.

BACKGROUND: Choosing treatments for epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients with osimertinib resistance is challenging. We evaluated the safety and efficacy of SNK01 (autologous natural killer (NK) cells) in combination with cytotoxic chemotherapy and/or cetuximab (an anti-EGFR monoclonal antibody) in treating EGFR-mutated NSCLC in this non-clinical and phase I/IIa clinical trial. METHODS: We developed a cell line-derived xenograft-humanized mouse model with an osimertinib-resistant lung cancer cell line. The mice were divided into four groups based on treatment (no treatment, cetuximab, SNK01, and combination groups) and treated weekly for 5 weeks. In the clinical study, 12 patients with EGFR-mutated NSCLC who failed prior tyrosine kinase inhibitor (TKI) received SNK01 weekly in combination with gemcitabine/carboplatin (n=6) or cetuximab/gemcitabine/carboplatin (n=6) and dose escalation of SNK01 following the "3+3" design. RESULTS: In the non-clinical study, an increase in NK cells in the blood and enhanced NK cell tumor infiltration were observed in the SNK01 group. The volume of tumor extracted after treatment was the smallest in the combination group. In the clinical study, 12 patients (median age, 60.9 years; all adenocarcinoma cases) received SNK01 weekly for 7-8 weeks (4×109 cells/dose (n=6); 6×109 cells/dose (n=6)). The maximum feasible dose of SNK01 was 6×109 cells/dose without dose-limiting toxicity. Efficacy outcomes showed an objective response rate of 25%, disease control rate of 100%, and median progression-free survival of 143 days. CONCLUSION: SNK01 in combination with cytotoxic chemotherapy, including cetuximab, for EGFR-mutated NSCLC with TKI resistance was safe and exerted a potential antitumor effect. TRIAL REGISTRATION NUMBER: NCT04872634.

Clinical characteristics and outcome of lung cancer in patients with fibrosing interstitial lung disease.

BACKGROUND: Lung cancer (LC) is an important comorbidity of interstitial lung disease (ILD) and has a poor prognosis. The clinical characteristics and outcome of each ILD subtype in LC patients have not been sufficiently investigated. Therefore, this study aimed to evaluate the difference between idiopathic pulmonary fibrosis (IPF) and non-IPF ILD as well as prognostic factors in patients with ILD-LC. METHODS: The medical records of 163 patients diagnosed with ILD-LC at Asan Medical Center from January 2018 to May 2023 were retrospectively reviewed. Baseline characteristics and clinical outcomes were compared between the IPF-LC and non-IPF ILD-LC groups, and prognostic factors were analyzed using the Cox proportional-hazard model. RESULTS: The median follow-up period was 11 months after the cancer diagnosis. No statistically significant differences were observed in clinical characteristics and mortality rates (median survival: 26 vs. 20 months, p = 0.530) between the groups. The independent prognostic factors in patients with ILD-LC were higher level of Krebs von den Lungen-6 (≥ 1000 U/mL, hazard ratio [HR] 1.970, 95% confidence interval [CI] 1.026-3.783, p = 0.025) and advanced clinical stage of LC (compared with stage I, HR 3.876 for stage II, p = 0.025, HR 5.092 for stage III, p = 0.002, and HR 5.626 for stage IV, p = 0.002). In terms of treatment, surgery was the significant factor for survival (HR 0.235; 95% CI 0.106-0.520; p < 0.001). CONCLUSIONS: No survival difference was observed between IPF-LC and non-IPF ILD-LC patients. A higher level of Krebs von den Lungen-6 may act as a prognostic marker in ILD-LC patients.

The Real-World Outcome of First Line Atezolizumab in Extensive-Stage Small Cell Lung Cancer: A Multicenter Prospective Cohort Study.

PURPOSE: The addition of immune checkpoint inhibitors to chemotherapy has improved survival outcomes in patients with extensive-stage small cell lung cancer (ES-SCLC). However, their real-world effectiveness remains unknown. Therefore, we investigated the effectiveness of atezolizumab plus chemotherapy in ES-SCLC in actual clinical settings. MATERIALS AND METHODS: In this multicenter prospective cohort study, patients with ES-SCLC receiving or scheduled to receive atezolizumab in combination with etoposide and carboplatin were enrolled between June 2021 and August 2022. The primary outcomes were progression-free survival (PFS) and the 1-year overall survival (OS) rate. RESULTS: A total of 100 patients with ES-SCLC were enrolled from seven centers. Median age was 69 years, and 6% had an Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 2. The median PFS was 6.0 months, the 1-year OS rate was 62.2%, and the median OS was 13.5 months. An ECOG PS of 2-3 and progressive disease as the best response were poor prognostic factors for PFS, while an ECOG PS of 2-3 and brain metastasis were associated with poor prognosis for OS. In addition, consolidative thoracic radiotherapy was found to be an independent favorable prognostic factor for OS (hazard ratio, 0.336; p=0.021). Grade ≥ 3 treatment-related adverse events were observed in 7% of patients, with treatment-related deaths occurring in 2% of patients. CONCLUSION: We provided evidence of the favorable real-world effectiveness and safety of atezolizumab plus chemotherapy in ES-SCLC patients, including in the elderly and those with poor ECOG PS. Additional consolidative thoracic radiotherapy may also benefit ES-SCLC patients.

Real-World Treatment Outcomes and Safety of Afatinib in Advanced Squamous Cell Lung Cancer Progressed after Platinum-Based Doublet Chemotherapy and Immunotherapy (SPACE Study).

This study aimed to evaluate treatment outcomes and safety of afatinib in patients with squamous cell carcinoma of the lung (LSCC) who progressed after chemotherapy and immunotherapy. We recruited patients both retrospectively and prospectively and collected the outcomes and safety data. Additionally, we performed next-generation sequencing using tumor tissue and/or plasma to explore potential molecular biomarkers. Altogether, 42 patients were included in the final analysis. The median number of prior treatments was three (range 1-8), and the median TTF was 2.1 months. Objective response rate and disease control rate were 16.2% and 59.5%, respectively, and median duration of response was 4.0 months among response evaluable patients (n = 37). Treatment-related adverse events (TRAEs, including diarrhea, stomatitis, and paronychia) occurred in 22 (52.3%) patients; however, most were grade 2 or lower, and only 5 cases were grade 3. TRAEs led to dose modification in 17 (40.5%) and discontinuation in 4 (9.5%) patients. The TTF in patients with ERBB2 mutations was significantly longer than that in patients without (6.8 vs. 2.1 months, p = 0.045). Our results highlight that afatinib is a reasonable treatment option in terms of effectiveness and safety, and ERBB2 mutation can be used as a predictive biomarker in clinical settings.

Nivolumab as maintenance therapy following platinum-based chemotherapy in EGFR-mutant lung cancer patients after tyrosine kinase inhibitor failure: A single-arm, open-label, phase 2 trial.

BACKGROUND: As the outcome of immunotherapy can be improved when concurrently or sequentially combined with cytotoxic chemotherapy or radiotherapy, we investigated the efficacy of immunotherapy maintenance following platinum-based chemotherapy in epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) after EGFR-tyrosine kinase inhibitor (EGFR-TKI) failure. METHODS: In this prospective, open-label, single arm phase 2 trial, we enrolled patients aged 18 years or older with EGFR-mutant NSCLC, which progressed after first- or second-line EGFR-TKI. Patients received platinum-based chemotherapy followed by nivolumab maintenance therapy. They were intravenously administered 240 mg of nivolumab every 2 weeks for 3 months followed by 480 mg every 4 weeks until disease progression or unacceptable toxic effects occurred. The primary endpoint was progression-free survival (PFS). Secondary outcomes were overall survival (OS) and incidence of grade 3-4 treatment-related adverse events (AEs). RESULTS: We enrolled 26 patients between May 2020 and July 2021. The median PFS was 1.7 months (95% CI: 0.401-2.999 months). The median OS was 21.4 months (95% CI: 18.790-24.010 months) with 6- and 12-month OS rates of 96.2% and 76.9%, respectively. The objective response rate was 7.7% (2/26) and disease control rate, 11.5% (3/26). The tumor mutational burden by next-generation sequencing in blood was not related to the treatment outcomes. Grade 3-4 treatment-related AEs occurred in four (15.4%) patients; the most frequent AE was increased alanine aminotransferase (7.7%). CONCLUSION: Nivolumab maintenance following platinum-based chemotherapy did not show clinical benefits after EGFR-TKI failure in patients with EGFR-mutant NSCLC.

Clinical characteristics and prognostic impact of acute exacerbations in patients with interstitial lung disease and lung cancer: A single-center, retrospective cohort study.

BACKGROUND: Although acute exacerbation (AE) after treatment for lung cancer (LC) is a poor prognostic factor in patients with interstitial lung disease associated with lung cancer (ILD-LC), the risk of AE according to cancer treatment type remains unclear. Therefore, in the present study, we aimed to investigate the association between AE and treatment received for LC in patients with ILD-LC. METHODS: We conducted a retrospective study of patients with ILD-LC who had undergone treatment for LC between January 2018 and December 2022. The primary study outcome was the incidence of AE within 12 months of treatment for LC according to treatment type. The association between AE and all-cause mortality was evaluated as a secondary outcome. RESULTS: Among a total of 137 patients, 23 (16.8%) developed AE within 12 months of treatment for LC. The incidence of AE according to treatment type was 4.3% for surgery, 16.2% for radiotherapy, 15.6% for chemotherapy, and 54.5% for concurrent chemoradiation therapy (CCRT). Patients who received CCRT were more likely to develop AE, even after adjustment for covariables (hazard ratio [HR], 15.39; 95% confidence interval [CI]: 4.00-59.19; p < 0.001). In addition, AE within 12 months of treatment for LC was associated with an increased risk of all-cause mortality (HR, 2.82; 95% CI: 1.13-7.04; p = 0.026). CONCLUSION: Among treatment options for patients with ILD-LC, CCRT was associated with an increased risk for AE. In addition, patients with AE had a higher mortality rate than patients without AE.

AXL receptor tyrosine kinase inhibition improves the anti-tumor effects of CD8+ T cells by inducing CD103+ dendritic cell-mediated T cell priming.

AXL is a member of TAM receptor family and has been highlighted as a potential target for cancer treatment. Accumulating evidence has uncovered the critical role of the AXL signaling pathway in tumor growth, metastasis, and resistance against anti-cancer drugs, as well as its association with cancer immune escape. However, the function of AXL as a manipulator of the immune system in the tumor microenvironment (TME) remains unclear. Therefore, in this study, we investigated the impact of AXL on immune cells in the TME of a syngeneic tumor model using AXL knockout (AXL-/-) mice. Compared to AXL wild-type (AXL+/+) mice, tumor growth was significantly suppressed in AXL-/- mice, and an induced population of tumor-infiltrated CD8+ T cells and CD103+ dendritic cells (DCs) was observed. The change of CD8+ T cells and CD103+ DCs was also confirmed in tumor-draining lymph nodes (TdLN). In addition, the clonal expansion of OVA-specific CD8+ T cells was dominant in AXL-/- mice. Finally, anti-PD-1 treatment evidenced synergistic anti-cancer effects in AXL-/- mice. Overall, our data indicate that AXL signaling may inhibit the clonal expansion of tumor-specific CD8+ T cells through the regulation of the migration of CD8+ T cells and DCs in TME. Thus, AXL may be a powerful molecular target to improve anti-cancer effects through single or combined therapy with immune checkpoint inhibitors (ICI).

Identification of exosomal microRNA panel as diagnostic and prognostic biomarker for small cell lung cancer.

BACKGROUND: Small cell lung cancer (SCLC) has an exceptionally poor prognosis; as most of the cases are initially diagnosed as extensive disease with hematogenous metastasis. Therefore, the early diagnosis of SCLC is very important and may improve its prognosis. METHODS: To investigate the feasibility of early diagnosis of SCLC, we examined exosomal microRNAs (miRNAs) present in serum obtained from patients with SCLC. First, exosomes were isolated in serum from patients with SCLC and healthy individuals and were characterized using particle size and protein markers. Additionally, miRNA array was performed to define SCLC-specific exosomal miRNAs. Second, the obtained miRNAs were further validated employing a large cohort. Finally, the ability to diagnose SCLC was estimated by area under the curve (AUC), and intracellular mRNA change patterns were verified through validated miRNAs. RESULTS: From the miRNA array results, we selected 51-miRNAs based on p-values and top 10 differentially expressed genes, and 25-miRNAs were validated using quantitative reverse transcription-polymerase chain reaction. The 25-miRNAs were further validated employing a large cohort. Among them, 7-miRNAs showed significant differences. Furthermore, 6-miRNAs (miR-3565, miR-3124-5p, miR-200b-3p, miR-6515, miR-3126-3p and miR-9-5p) were up-regulated and 1-miRNA (miR-92b-5p) was down-regulated. The AUC value of each miRNA sets between 0.64 and 0.76, however the combined application of 3-miRNAs (miR-200b-3p, miR-3124-5p and miR-92b-5p) remarkably improved the diagnostic value (AUC = 0.93). Gene ontology analysis revealed that the 3-miRNA panel is linked to various oncogene pathways and nervous system development. When the 3-miRNAs were introduced to cells, the resulting changes in total mRNA expression strongly indicated the presence of lung diseases, including lung cancer. In addition, the 3-miRNA panel was significantly associated with a poorer prognosis, although individual miRNAs have not been validated as prognostic markers. CONCLUSION: Our study identified SCLC-specific exosomal miRNAs, and the 3-miRNAs panel (miR-200b-3p, miR-3124-5p and miR-92b-5p) may serve as a diagnostic and prognostic marker for SCLC.

Clinical Outcomes of Bronchoscopic Cryotherapy for Central Airway Obstruction in Adults: An 11-Years' Experience of a Single Center.

BACKGROUND: Although bronchoscopic cryotherapy (BC) is a pragmatic modality for recanalization of central airway obstruction (CAO), the risk of complications, such as bleeding, remains a concern. This study aimed to present the clinical outcomes of BC and evaluate the factors associated with its complications. METHODS: In this retrospective study, we reviewed the medical records of patients who underwent BC for CAO at the Asan Medical Center, South Korea. Most sessions were conducted via flexible bronchoscopy under moderate sedation. A multivariate logistic regression analysis was used to identify the factors associated with the success rate and complications. RESULTS: BC was performed in 262 sessions in 208 patients between January 2009 and December 2020. The most common cause of cryotherapy was recanalization of the endobronchial tumor related CAO (233/262, 88.9%). More than partial re-establishment of airway patency was achieved in 211 of 233 (90.6%) sessions. The success rate did not differ significantly in the multivariate logistic regression analysis. The most common complication was intrabronchial bleeding (78/233, 35.5%); however, severe bleeding occurred only in one case (0.4%). Univariate and multivariate logistic regression analyses revealed that diabetes mellitus (odds ratio [OR] = 2.820, P = 0.011), respiratory failure before BC (OR = 3.546, P = 0.028), and presence of distal airway atelectasis (OR = 0.417, P = 0.021) were independently associated with moderate to severe intrabronchial bleeding, while the histologic type of tumor was not related to bleeding. BC for CAO caused by blood clot or foreign body was successful in most cases, and there were no complications. CONCLUSION: BC is an efficient and relatively safe intervention for patients with CAO. Our findings suggest that diabetes, respiratory failure before BC, and the absence of distal airway atelectasis may be risk factors of moderate to severe intrabronchial bleeding.

Cancer-Related Dysfunctional Beliefs About Sleep Mediate the Influence of Sleep Disturbance on Fear of Progression Among Patients With Surgically Resected Lung Cancer.

BACKGROUND: Lung cancer is associated with significant psychological distress, including fear of progression (FoP). Because insomnia and depression are highly prevalent and associated with FoP, we examined the association between FoP, insomnia, and depression in cancer patients. Furthermore, we tested the mediation effect of cancer-related dysfunctional beliefs about sleep (C-DBS) on this association. METHODS: We analyzed data collected from patients with surgically resected non-small cell lung cancer from a single-center randomized controlled study investigating digital healthcare applications. Baseline demographic and clinical variables were collected. In addition, self-reported questionnaires including the Fear of Progression Questionnaire-Short Form, Patients Health Questionnaire-9 items (PHQ-9), Insomnia Severity Index, and C-DBS were administered. RESULTS: Among the 320 enrolled patients with lung cancer, a regression model showed that FoP was predicted by age (ß = -0.13, P = 0.007), PHQ-9 (ß = 0.35, P < 0.001), and C-DBS (ß = 0.28, P < 0.001). Insomnia did not directly influence FoP, but C-DBS mediated the association. Depression directly influenced FoP, but C-DBS did not mediate this association. CONCLUSION: Among patients with surgically resected lung cancer, C-DBS mediated the effects of severity of insomnia on FoP. Depression directly influenced FoP, but C-DBS did not influence this association. To reduce FoP among patients with lung cancer, C-DBS should be addressed in the cognitive behavioral therapy module.

Efficacy of lazertinib for symptomatic or asymptomatic brain metastases in treatment-naive patients with advanced EGFR mutation-positive non-small cell lung cancer: Protocol of an open-label, single-arm phase II trial.

INTRODUCTION: Non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation has a higher incidence of brain metastases than wild-type EGFR mutations. Osimertinib, a third-generation EGFR tyrosine kinase inhibitor (TKI), targets both EGFR-TKI sensitizing and T790M-resistance mutations and has a higher brain penetration rate relative to first- and second-generation EGFR-TKIs. Therefore, osimertinib has become a preferred first-line therapy for advanced EGFR mutation-positive NSCLC. However, lazertinib, an emerging EGFR-TKI, has shown higher selectivity toward EGFR mutations and improved penetration of the blood-brain barrier compared to osimertinib in preclinical studies. This trial will evaluate the efficacy of lazertinib as a first-line therapy in patients with EGFR mutation-positive NSCLC who have brain metastases, with or without additional local therapy. METHODS: This is a single-center, open-label, single-arm phase II trial. A total of 75 patients with advanced EGFR mutation-positive NSCLC will be recruited. Eligible patients will receive oral lazertinib 240 mg, once daily until disease progression or intolerable toxicity is detected. Patients with moderate to severe symptoms related to brain metastasis will simultaneously receive local therapy for the brain. The primary endpoints are progression-free survival and intracranial progression-free survival. DISCUSSION: Lazertinib, in combination with local therapy for the brain, if necessary, is expected to improve the clinical benefit in advanced EGFR mutation-positive NSCLC with brain metastases, as a first-line treatment.

Korean Real-World Data on Patients With Unresectable Stage III NSCLC Treated With Durvalumab After Chemoradiotherapy: PACIFIC-KR.

INTRODUCTION: This study aimed to investigate real-world evidence for efficacy and safety of durvalumab consolidation (DC) after chemoradiotherapy (CRT) in patients with unresectable stage III NSCLC. METHODS: Patients with stage III NSCLC who started DC after CRT between September 2018 and December 2020 and were treated at five tertiary hospitals in the Republic of Korea were included. The primary end point was real-world progression-free survival (rwPFS). Secondary end points were overall survival, objective response rate, and adverse events including radiation pneumonitis (RP) and immune-related adverse events (irAEs). RESULTS: A total of 157 patients were enrolled. At the median follow-up of 19.1 months, median rwPFS of DC was 25.9 months (95% confidence interval: 16.5-35.4) and the 1-, 2-, and 3-year rwPFS rates were 59.4%, 51.8%, and 43.5%, respectively. The median overall survival was not mature, and objective response rate of DC was 51.0%. High programmed death-ligand 1 expression (≥50%) and development of RP requiring steroid treatment were significantly associated with longer (p = 0.043) and shorter rwPFS (p = 0.036), respectively. RP, RP requiring steroid treatment, and irAEs developed in 57 (36.3%), 42 (26.8%), and 53 (33.8%) patients, respectively. Among peripheral blood cell counts at the initiation of DC, a high derived monocyte-to-lymphocyte ratio was the most significant risk factor for the development of RP requiring steroid treatment (OR 44.76, 95% CI: 8.89-225.43, p < 0.001) and irAEs (OR 2.85, 95% CI: 1.27-6.41, p = 0.011). CONCLUSIONS: Compared with the outcome of the PACIFIC trial, these real-world data revealed favorable survival benefits of DC after CRT in patients with unresectable stage III NSCLC. Blood-based biomarkers could predict higher-grade RP and irAEs before the initiation of DC.

Prediction Models for Mediastinal Metastasis and Its Detection by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration in Potentially Operable Non-Small Cell Lung Cancer: A Prospective Study.

BACKGROUND: Prediction models for mediastinal metastasis and its detection by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) have not been developed using a prospective cohort of potentially operable patients with non-small cell lung cancer (NSCLC). RESEARCH QUESTION: Can mediastinal metastasis and its detection by EBUS-TBNA be predicted with prediction models in NSCLC? STUDY DESIGN AND METHODS: For the prospective development cohort, 589 potentially operable patients with NSCLC were evaluated (July 2016-June 2019) from five Korean teaching hospitals. Mediastinal staging was performed using EBUS-TBNA (with or without the transesophageal approach). Surgery was performed for patients without clinical N (cN) 2-3 disease by endoscopic staging. The prediction model for lung cancer staging-mediastinal metastasis (PLUS-M) and a model for mediastinal metastasis detection by EBUS-TBNA (PLUS-E) were developed using multivariable logistic regression analyses. Validation was performed using a retrospective cohort (n = 309) from a different period (June 2019-August 2021). RESULTS: The prevalence of mediastinal metastasis diagnosed by EBUS-TBNA or surgery and the sensitivity of EBUS-TBNA in the development cohort were 35.3% and 87.0%, respectively. In PLUS-M, younger age (< 60 years and 60-70 years compared with ≥ 70 years), nonsquamous histology (adenocarcinoma and others), central tumor location, tumor size (> 3-5 cm), cN1 or cN2-3 stage by CT, and cN1 or cN2-3 stage by PET-CT were significant risk factors for N2-3 disease. Areas under the receiver operating characteristic curve (AUCs) for PLUS-M and PLUS-E were 0.876 (95% CI, 0.845-0.906) and 0.889 (95% CI, 0.859-0.918), respectively. Model fit was good (PLUS-M: Hosmer-Lemeshow P = .658, Brier score = 0.129; PLUS-E: Hosmer-Lemeshow P = .569, Brier score = 0.118). In the validation cohort, PLUS-M (AUC, 0.859 [95% CI, 0.817-0.902], Hosmer-Lemeshow P = .609, Brier score = 0.144) and PLUS-E (AUC, 0.900 [95% CI, 0.865-0.936], Hosmer-Lemeshow P = .361, Brier score = 0.112) showed good discrimination ability and calibration. INTERPRETATION: PLUS-M and PLUS-E can be used effectively for decision-making for invasive mediastinal staging in NSCLC. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT02991924; URL: www. CLINICALTRIALS: gov.

Clinical Outcome of Stereotactic Body Radiotherapy in Patients with Early-Stage Lung Cancer with Ground-Glass Opacity Predominant Lesions: A Single Institution Experience.

PURPOSE: The detection rate of early-stage lung cancer with ground-glass opacity (GGO) has increased, and stereotactic body radiotherapy (SBRT) has been suggested as an alternative to surgery in inoperable patients. However, reports on treatment results are limited. Therefore, we performed a retrospective study to investigate the clinical outcome after SBRT in patients with early-stage lung cancer with GGO-predominant tumor lesions at a single institution. MATERIALS AND METHODS: This study included 89 patients with 99 lesions who were treated with SBRT for lung cancer with GGO-predominant lesions that had a consolidation-to-tumor ratio of ≤0.5 at Asan Medical Center between July 2016 and July 2021. A median total dose of 56.0 Gy (range, 48.0-60.0) was delivered using 10.0-15.0 Gy per fraction. RESULTS: The overall follow-up period for the study was median 33.0 months (range, 9.9 to 65.9 months). There was 100% local control with no recurrences in any of the 99 treated lesions. Three patients had regional recurrences outside of the radiation field, and three had distant metastasis. The 1-year, 3-year, and 5-year overall survival rates were 100.0%, 91.6%, and 82.8%, respectively. Univariate analysis revealed that advanced age and a low level of diffusing capacity of the lungs for carbon monoxide were significantly associated with overall survival. There were no patients with grade ≥3 toxicity. CONCLUSION: SBRT is a safe and effective treatment for patients with GGO-predominant lung cancer lesions and is likely to be considered as an alternative to surgery.

Stratifying non-small cell lung cancer patients using an inverse of the treatment decision rules: validation using electronic health records with application to an administrative database.

BACKGROUND: To validate a stratification method using an inverse of treatment decision rules that can classify non-small cell lung cancer (NSCLC) patients in real-world treatment records. METHODS: (1) To validate the index classifier against the TNM 7th edition, we analyzed electronic health records of NSCLC patients diagnosed from 2011 to 2015 in a tertiary referral hospital in Seoul, Korea. Predictive accuracy, stage-specific sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and c-statistic were measured. (2) To apply the index classifier in an administrative database, we analyzed NSCLC patients in Korean National Health Insurance Database, 2002-2013. Differential survival rates among the classes were examined with the log-rank test, and class-specific survival rates were compared with the reference survival rates. RESULTS: (1) In the validation study (N = 1375), the overall accuracy was 93.8% (95% CI: 92.5-95.0%). Stage-specific c-statistic was the highest for stage I (0.97, 95% CI: 0.96-0.98) and the lowest for stage III (0.82, 95% CI: 0.77-0.87). (2) In the application study (N = 71,593), the index classifier showed a tendency for differentiating survival probabilities among classes. Compared to the reference TNM survival rates, the index classification under-estimated the survival probability for stages IA, IIIB, and IV, and over-estimated it for stages IIA and IIB. CONCLUSION: The inverse of the treatment decision rules has a potential to supplement a routinely collected database with information encoded in the treatment decision rules to classify NSCLC patients. It requires further validation and replication in multiple clinical settings.

Trends and an Online Survey on the Use of Rigid Bronchoscopy in Korea.

BACKGROUND: Although almost all interventional pulmonologists agree that rigid bronchoscopy is irreplaceable in the field of interventional pulmonology, less is known about the types of diseases that the procedure is used for and what difficulties the operators face during the procedure. The purpose of this study is to evaluate what diseases rigid bronchoscopy is used for, whether it is widely used, and what challenges the operators face in Korea. METHODS: We enrolled 14 hospitals in this retrospective cohort of patients who underwent rigid bronchoscopy between 2003 and 2020. An online survey was conducted with 14 operators to investigate the difficulties associated with the procedure. RESULTS: While the number of new patients at Samsung Medical Center (SMC) increased from 189 in 2003-2005 to 468 in 2018-2020, that of other institutions increased from 0 to 238. The proportion of SMC patients in the total started at 100% and steadily decreased to 59.2%. The proportion of malignancy as the indication for the procedure steadily increased from 29.1% to 43.0%, whereas post-tuberculous stenosis (25.4% to 12.9%) and post-intubation stenosis (19.0% to 10.9%) steadily decreased (all P for trends < 0.001). In the online survey, half of the respondents stated that over the past year they performed less than one procedure per month. The fewer the procedures performed within the last year, the more likely collaboration with other departments was viewed as a recent obstacle (Spearman correlation coefficient, rs = -0.740, P = 0.003) and recent administrative difficulties were encountered (rs = -0.616, P = 0.019). CONCLUSION: This study demonstrated that the number of patients undergoing rigid bronchoscopy has been increasing, especially among cancer patients. For this procedure to be used more widely, it will be important for beginners to systematically learn about the procedure itself as well as to achieve multidisciplinary consultation.

Optimal Definition of Oligometastasis Showing Survival Benefits of Local Therapies during Tyrosine Kinase Inhibitor Treatment.

PURPOSE: We aimed to investigate the feasibility of four criteria on oligometastasis (OM) concerning clear survival benefits of local therapy (LT) during tyrosine kinase inhibitor (TKI) treatment in non-small cell lung cancer (NSCLC). Materials and Methods: This single-center, retrospective study included patients with advanced NSCLC who received LT because of OM during TKI treatment at Asan Medical Center from January 2011 to December 2020. At the application of LT OM was classified according to four criteria: TNM, European Organization for Research and Treatment of Cancer Lung Cancer Group (EORTC-LCG), National Comprehensive Network (NCCN), and ORGAN. We compared survival outcomes between patients with and without OM. RESULTS: The median overall survival of the 117 patients included in the analysis was 70.8 months (95% confidence interval [CI], 56.6 to 85.1). The patients with OM meeting all four criteria (hazard ratio [HR] with 95% CI of TNM criteria 0.24 with 0.10-0.57; p=0.001, EORTC-LCG criteria 0.34 with 0.17-0.67; p=0.002, NCCN criteria 0.41 with 0.20-0.86; p=0.018 and ORGAN criteria 0.33 with 0.18-0.60; p < 0.001) had significantly longer survival compared with patients who did not after adjusting for confounding factors. Furthermore, increasing the number of extra-thoracic metastatic organs to two or more were independent predictive factors for worse survival outcomes (2 organs: HR, 3.51; 95% CI, 1.01 to 12.14; p=0.048; 3 organs: HR, 4.31; 95% CI, 0.94 to 19.73; p=0.060; 4 organs: HR, 24.47; 95% CI, 5.08 to 117.80; p < 0.001). CONCLUSION: Patients with OM defined by all four criteria showed prognostic benefits from LT during TKI therapy.