Distinguishing thymic cysts from low-risk thymomas via [18F]FDG PET/CT

BACKGROUND

Thymic cysts are a rare benign disease that needs to be distinguished from low-risk thymoma. [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is a non-invasive imaging technique used in the differential diagnosis of thymic epithelial tumours, but its usefulness for thymic cysts remains unclear. Our study evaluated the utility of visual findings and quantitative parameters of [18F]FDG PET/CT for differentiating between thymic cysts and low-risk thymomas.

METHODS

Patients who underwent preoperative [18F]FDG PET/CT followed by thymectomy for a thymic mass were retrospectively analyzed. The visual [18F]FDG PET/CT findings evaluated were PET visual grade, PET central metabolic defect, and CT shape. The quantitative [18F]FDG PET/CT parameters evaluated were PET maximum standardized uptake value (SUVmax), CT diameter (cm), and CT attenuation in Hounsfield units (HU). Findings and parameters for differentiating thymic cysts from low-risk thymomas were assessed using Pearson's chi-square test, the Mann-Whitney U-test, and receiver operating characteristics (ROC) curve analysis.

RESULTS

Seventy patients (18 thymic cysts and 52 low-risk thymomas) were finally included. Visual findings of PET visual grade (P < 0.001) and PET central metabolic defect (P < 0.001) showed significant differences between thymic cysts and low-risk thymomas, but CT shape did not. Among the quantitative parameters, PET SUVmax (P < 0.001), CT diameter (P < 0.001), and CT HU (P = 0.004) showed significant differences. In ROC analysis, PET SUVmax demonstrated the highest area under the curve (AUC) of 0.996 (P < 0.001), with a cut-off of equal to or less than 2.1 having a sensitivity of 100.0% and specificity of 94.2%. The AUC of PET SUVmax was significantly larger than that of CT diameter (P = 0.009) and CT HU (P = 0.004).

CONCLUSIONS

Among the [18F]FDG PET/CT parameters examined, low FDG uptake (SUVmax ≤ 2.1, equal to or less than the mediastinum) is a strong diagnostic marker for a thymic cyst. PET visual grade and central metabolic defect are easily accessible findings.

Validation Study for the N Descriptor of the Newly Proposed Ninth Edition of the TNM Staging System Proposed by the International Association for the Study of Lung Cancer

INTRODUCTION

The aim of this study was to validate the discriminatory ability and clinical utility of the N descriptor of the newly proposed ninth edition of the TNM staging system for lung cancer in a large independent cohort.

METHODS

We retrospectively analyzed patients who underwent curative surgery for NSCLC between January 2004 and December 2019. The N descriptor of patients included in this study was retrospectively reclassified based on the ninth edition of the TNM classification. Survival analysis was performed using the log-rank test and Cox proportional hazard model to compare adjacent N categories.

RESULTS

A total of 6649 patients were included in this study. The median follow-up period was 54 months. According to the newly proposed ninth edition N classification, 5573 patients (83.8%), 639 patients (9.6%), 268 patients (4.0%), and 169 patients (2.5%) were classified into the clinical N0, N1, N2a, and N2b categories and 4957 patients (74.6%), 744 patients (11.2%), 567 patients (8.5%), and 381 patients (5.7%) were classified into the pathologic N0, N1, N2a, and N2b categories, respectively. The prognostic differences between all adjacent clinical and pathologic N categories were highly significant in terms of both overall survival and recurrence-free survival.

CONCLUSIONS

We validated the clinical utility of the newly proposed ninth edition N classification for both clinical and pathologic stages in NSCLC. The new N classification revealed clear prognostic separation between all categories (N0, N1, N2a, and N2b) in terms of both overall survival and recurrence-free survival.

Pre-operative clonal hematopoiesis is related to adverse outcome in lung cancer after adjuvant therapy

BACKGROUND

Clonal hematopoiesis (CH) frequently progresses after chemotherapy or radiotherapy. We evaluated the clinical impact of preoperative CH on the survival outcomes of patients with non-small cell lung cancer (NSCLC) who underwent surgical resection followed by adjuvant therapy.

METHODS

A total of 415 consecutive patients with NSCLC who underwent surgery followed by adjuvant therapy from 2011 to 2017 were analyzed. CH status was evaluated using targeted deep sequencing of blood samples collected before surgery. To minimize the possible selection bias between the two groups according to CH status, a propensity score matching (PSM) was adopted. Early-stage patients were further analyzed with additional matched cohort of patients who did not receive adjuvant therapy.

RESULTS

CH was detected in 21% (86/415) of patients with NSCLC before adjuvant therapy. Patients with CH mutations had worse overall survival (OS) than those without (hazard ratio [95% confidence interval] = 1.56 [1.07-2.28], p = 0.020), which remained significant after the multivariable analysis (1.58 [1.08-2.32], p = 0.019). Of note, the presence of CH was associated with non-cancer mortality (p = 0.042) and mortality of unknown origin (p = 0.018). In patients with stage IIB NSCLC, there was a significant interaction on OS between CH and adjuvant therapy after the adjustment with several cofactors through the multivariable analysis (HR 1.19, 95% CI 1.00-1.1.41, p = 0.041).

CONCLUSIONS

In resected NSCLC, existence of preoperative CH might amplify CH-related adverse outcomes through adjuvant treatments, resulting in poor survival results.

Clinical impact of pre-existing acute exacerbation in patients with interstitial lung disease who underwent lung transplantation

BACKGROUND

Acute exacerbation of interstitial lung disease (AE-ILD) significantly impacts prognosis, leading to high mortality rates. Although lung transplantation is a life-saving treatment for selected patients with ILD, its outcomes in those presenting with AE-ILD have yielded conflicting results compared with those with stable ILD. This study aims to investigate the impact of pre-existing AE on the prognosis of ILD patients who underwent lung transplantation.

METHOD

We conducted a single-center retrospective study by reviewing the medical records of 108 patients who underwent lung transplantation for predisposing ILD at Asan Medical Center, Seoul, South Korea, between 2008 and 2022. The primary objective was to compare the survival of patients with AE-ILD at the time of transplantation with those without AE-ILD.

RESULTS

Among the 108 patients, 52 (48.1%) experienced AE-ILD at the time of lung transplantation, and 81 (75.0%) required pre-transplant mechanical ventilation. Although the type of ILD (IPF vs. non-IPF ILD) did not affect clinical outcomes after transplantation, AE-ILD was associated with worse survival outcomes. The survival probabilities at 90 days, 1 year, and 3 years post-transplant for patients with AE-ILD were 86.5%, 73.1%, and 60.1%, respectively, while those for patients without AE-ILD were higher, at 92.9%, 83.9%, and 79.6% (p = 0.032). In the multivariable analysis, pre-existing AE was an independent prognostic factor for mortality in ILD patients who underwent lung transplantation.

CONCLUSIONS

Although lung transplantation remains an effective treatment option for ILD patients with pre-existing AE, careful consideration is needed, especially in patients requiring pre-transplant mechanical respiratory support.

E3 ligase SOCS3 regulates NOD2 expression by ubiquitin proteasome system in lung cancer progression

PURPOSE

Despite lung cancer is one of the leading causes of cancer-related deaths, it remains hard to discover effective diagnostic and therapeutic approaches. Moreover, the five-year survival rate is relatively lower than other tumors. So urgent needs for finding a new theranostic target to treat lung cancer effectively. This study aims to present SOCS3 and NOD2 proteins as novel targets for diagnosis and therapy.

METHODS

We first confirmed SOCS3 expression level in patients' tissues. Then, we applied knockdown and overexpression of SOCS3 on lung cancer cell lines and performed proliferation, migration, and invasion assay. After that, we found NOD2 is a target of SOCS3 and introduced overexpression of NOD2 to A549 for verifying reduced tumorigenicity of lung cancer cells.

RESULTS

We identified protein expression level of SOCS3 was frequently higher in tumor tissues than adjacent normal tissues. Truly, overexpression of SOCS3 promoted proliferation, migration, and invasion capacity of lung cancer cells. We found that SOCS3 interacts with NOD2 and SOCS3 ubiquitinates NOD2 directly. Furthermore, lung cancer tissues with higher SOCS3 expression showed lower NOD2 expression. We confirmed overexpression of NOD2 leads to suppressed tumorigenicity of lung cancer cells, and these effects occurred through MAPK pathway.

CONCLUSION

Collectively, our work reveals novel roles of SOCS3 in lung tumorigenesis and proposes SOCS3 as a promising biomarker candidate for therapeutic and diagnostic target for lung cancer.

[18F]fluorodeoxyglucose positron emission tomography/computed tomography characteristics of primary mediastinal germ cell tumors

Primary mediastinal germ cell tumor (MGCT) is an uncommon tumor. Although it has histology similar to that of gonadal germ cell tumor (GCT), the prognosis for MGCT is generally worse than that for gonadal GCT. We performed visual assessment and quantitative analysis of [18F]fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET/CT) for MGCTs. A total of 35 MGCT patients (age = 33.1 ± 16.8 years, F:M = 16:19) who underwent preoperative PET/CT were retrospectively reviewed. The pathologic diagnosis of MGCTs identified 24 mature teratomas, 4 seminomas, 5 yolk sac tumors, and 2 mixed germ cell tumors. Visual assessment was performed by categorizing the uptake intensity, distribution, and contour of primary MGCTs. Quantitative parameters including the maximum standardized uptake value (SUVmax), tumor-to-background ratio (TBR), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum diameter were compared between benign and malignant MGCTs. On visual assessment, the uptake intensity was the only significant parameter for differentiating between benign and malignant MGCTs (p = 0.040). In quantitative analysis, the SUVmax (p < 0.001), TBR (p < 0.001), MTV (p = 0.033), and TLG (p < 0.001) showed significantly higher values for malignant MGCTs compared with benign MGCTs. In receiver operating characteristic (ROC) curve analysis of these quantitative parameters, the SUVmax had the highest area under the curve (AUC) (AUC = 0.947, p < 0.001). Furthermore, the SUVmax could differentiate between seminomas and nonseminomatous germ cell tumors (p = 0.042) and reflect serum alpha fetoprotein (AFP) levels (p = 0.012). The visual uptake intensity and SUVmax on [18F]FDG PET/CT showed discriminative ability for benign and malignant MGCTs. Moreover, the SUVmax may associate with AFP levels.

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 (β = -0.13, P = 0.007), PHQ-9 (β = 0.35, P < 0.001), and C-DBS (β = 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.

Evaluation of Chylothorax Using Dynamic Contrast-Enhanced Magnetic Resonance Lymphangiography After Lung Cancer Surgery

Background: To determine the role of dynamic contrast-enhanced magnetic resonance lymphangiography (DCMRL) in the management of postoperative chylothorax after lung cancer surgery. Methods and Results: Between July 2017 and November 2021, patients who developed postoperative chylothorax following pulmonary resection and mediastinal lymph node dissection were assessed and those who underwent DCMRL for the evaluation of chyle leak were evaluated. The findings of DCMRL and conventional lymphangiography were compared. The incidence of postoperative chylothorax was 0.9% (50/5587). Among the patients with chylothorax, a total of 22 patients (44.0% [22/50]; mean age, 67.6 ± 7.9 years; 15 men) underwent DCMRL. Treatment outcomes were compared between patients with conservative management (n = 10) and those with intervention (n = 12). The patients demonstrated unilateral pleural effusion, ipsilateral to the operation site, and showed right-sided dominance. The most frequent site of thoracic duct injury showing contrast media leakage was visualized at the subcarinal level. No DCMRL-related complication occurred. DCMRL showed comparable performance to conventional lymphangiography in visualizing the central lymphatics, including cisterna chyli (DCMRL vs. conventional lymphangiography, 72.7% vs. 45.5%, p = 0.25) and thoracic duct (90.9% vs. 54.5%, p = 0.13), and in localizing thoracic duct injury (90.9% vs. 54.5%, p = 0.13). On follow-up, the amount of chest tube drainage after lymphatic intervention showed a significant difference over time from that after medical treatment only (p = 0.02). Conclusion: DCMRL can provide detailed information about the leak site and the central lymphatic anatomy in patients with chylothorax after lung cancer surgery. The findings of DCMRL can guide subsequent treatment planning for optimal outcomes.

Prognostic significance of extranodal extension in patients with pathologic N1 non-small cell lung cancer undergoing complete resection

Background

The prognostic significance of extranodal extension (ENE) remains unclear in patients with pathologic N1 (pN1) non-small-cell lung cancer (NSCLC) undergoing surgery. We evaluated the prognostic impact of ENE in patients with pN1 NSCLC.

Methods

From 2004 to 2018, we retrospectively analyzed the data of 862 patients with pN1 NSCLC who underwent lobectomy and more (lobectomy, bilobectomy, pneumonectomy, sleeve lobectomy). According to their resection status and the presence of ENE, patients were classified into R0 without ENE (pure R0) (n=645), R0 with ENE (R0-ENE) (n=130), and incomplete resection (R1/R2) groups (n=87). The primary and secondary endpoints were 5-year overall survival (OS) and recurrence-free survival (RFS), respectively.

Results

The prognosis of the R0-ENE group was significantly worse than the pure R0 group for both OS (5-year rate: 51.6% vs. 65.4%, P=0.008) and RFS (44.4% vs. 53.0%, P=0.04). According to the recurrence pattern, a difference of RFS was found only for distant metastasis (55.2% vs. 65.0%, P=0.02). The multivariable Cox analysis revealed that the presence of ENE was a negative prognostic factor in patients who did not undergo adjuvant chemotherapy [hazard ratio (HR) =1.58; 95% confidence interval (CI): 1.06-2.36; P=0.03], but it was not in those with adjuvant chemotherapy (HR =1.20; 95% CI: 0.80-1.81; P=0.38).

Conclusions

For patients with pN1 NSCLC, the presence of ENE was a negative prognostic factor for both OS and RFS, regardless of resection status. The negative prognostic effect of ENE was significantly associated with an increase in distant metastasis and was not observed in patients who underwent adjuvant chemotherapy.

Early Outcomes of COVID-19 Lung Transplantation Recipients in Korea: A Single-Center Study

Background

Coronavirus disease 2019 (COVID-19) has been found to cause life-threatening respiratory failure, which can progress to irreversible lung damage. Lung transplantation can be a life-saving treatment in patients with terminal lung disease (e.g., acute respiratory distress syndrome caused by infection). This study aimed to present the clinical course and results after initial lung transplantation in patients with severe COVID-19 who did not recover even with optimal medical care.

Methods

From August 2019 to February 2022, this study enrolled 10 patients with COVID-19 (5 men; median age, 55.7 years) who underwent lung transplantation at a single center in Korea. All patients' characteristics, clinical pathway, overall survival, complications, and operative data were collected and analyzed.

Results

Veno-venous extracorporeal membrane oxygenation or an oxygenator in a right ventricular assist device circuit was applied to 90% of the patients, and the median length of extracorporeal life support before operation was 48.5 days. There were no cases of mortality after a median follow-up of 372.8 days (interquartile range, 262.25-489 days). The major complications included the requirement for postoperative extracorporeal membrane oxygenation support in 2 cases (20%), re-transplantation in 1 case (10%), and re-exploration due to bleeding in 2 cases (20%). During the follow-up period, 3 out of 10 patients died.

Conclusion

Excellent early outcomes were observed for patients who underwent lung transplantation. Thus, lung transplantation can be an effective and feasible treatment for patients with end-stage lung disease caused by COVID-19.

Long-term Surgical Outcomes in Oligometastatic Non-small Cell Lung Cancer: A Single-Center Study

Background

We reviewed the clinical outcomes of patients with oligometastatic (OM) non-small cell lung cancer (NSCLC) who received multimodal therapy including lung surgery.

Methods

We retrospectively analyzed 117 patients with OM NSCLC who underwent complete resection of the primary tumor from 2014 to 2017.

Results

The median follow-up duration was 2.91 years (95% confidence interval, 1.48-5.84 years). The patients included 73 men (62.4%), and 76 patients (64.9%) were under the age of 65 years. Based on histology, 97 adenocarcinomas and 14 squamous cell carcinomas were included. Biomarker analysis revealed that 53 patients tested positive for epidermal growth factor receptor, anaplastic lymphoma kinase, or ROS1 mutations, while 36 patients tested negative. Metastases were detected in the brain in 74 patients, the adrenal glands in 12 patients, bone in 5 patients, vertebrae in 4 patients, and other locations in 12 patients. Radiation therapy for organ metastasis was performed in 81 patients and surgical resection in 27 patients. The 1-year overall survival (OS) rate in these patients was 82.8%, and the 3- and 5-year OS rates were 52.6% and 37.2%, respectively. Patients with positive biomarker test results had 1-, 3-, and 5-year OS rates of 98%, 64%, and 42.7%, respectively. These patients had better OS than those with negative biomarker test results (p=0.031). Patients aged ≤65 years and those with pT1-2 cancers also showed better survival (both p=0.008).

Conclusion

Surgical resection of primary lung cancer is a viable treatment option for selected patients with OM NSCLC in the context of multimodal therapy.

The Role of Adjuvant Therapy Following Surgical Resection of Small Cell Lung Cancer: A Multi-Center Study

PURPOSE

This multi-center, retrospective study was conducted to evaluate the long-term survival in patients who underwent surgical resection for small cell lung cancer (SCLC) and to identify the benefit of adjuvant therapy following surgery.

MATERIALS AND METHODS

The data of 213 patients who underwent surgical resection for SCLC at four institutions were retrospectively reviewed. Patients who received neoadjuvant therapy or an incomplete resection were excluded.

RESULTS

The mean patient age was 65.29±8.93 years, and 184 patients (86.4%) were male. Lobectomies and pneumonectomies were performed in 173 patients (81.2%), and 198 (93%) underwent systematic mediastinal lymph node dissections. Overall, 170 patients (79.8%) underwent adjuvant chemotherapy, 42 (19.7%) underwent radiotherapy to the mediastinum, and 23 (10.8%) underwent prophylactic cranial irradiation. The median follow-up period was 31.08 months (interquartile range, 13.79 to 64.52 months). The 5-year overall survival (OS) and disease-free survival were 53.4% and 46.9%, respectively. The 5-year OS significantly improved after adjuvant chemotherapy in all patients (57.4% vs. 40.3%, p=0.007), and the survival benefit of adjuvant chemotherapy was significant in patients with negative node pathology (70.8% vs. 39.7%, p=0.004). Adjuvant radiotherapy did not affect the 5-year OS (54.6% vs. 48.5%, p=0.458). Age (hazard ratio [HR], 1.032; p=0.017), node metastasis (HR, 2.190; p < 0.001), and adjuvant chemotherapy (HR, 0.558; p=0.019) were associated with OS.

CONCLUSION

Adjuvant chemotherapy after surgical resection in patients with SCLC improved the OS, though adjuvant radiotherapy to the mediastinum did not improve the survival or decrease the locoregional recurrence rate.

Diagnostic value of 18F-FDG PET/CT in discriminating between benign and malignant lesions of the ribs

PURPOSE

Imaging biomarkers for rib mass are needed to optimize treatment plan. We investigated the diagnostic value of metabolic and volumetric parameters from 18F-fluorodeoxyglucose (FDG) positron-emission tomography/computed tomography (PET/CT) in discriminating between benign and malignant lesions of the ribs.

PATIENTS AND METHODS

Fifty-seven patients with pathologically proven diagnosis of rib lesions were retrospectively enrolled. The size of rib lesions, the maximum, mean, and peak standardized uptake value (SUVmax, SUVmean, SUVpeak), tumor-to-background ratio (TBR), metabolic tumor volume (MTV), and total lesions glycolysis (TLG) were measured. The FDG uptake patterns (segmental and discrete) and CT findings (soft tissue involvement and fracture) were also reviewed.

RESULTS

Among the multiple parameters extracted from PET/CT, the MTV of malignant lesions was significantly higher than that of benign lesions (median; 4.7 vs 0.2, respectively, P = .041). In receiver operating characteristics curve analysis, MTV had the largest area under curve of 0.672 for differentiating malignant from benign lesions. For identifying malignant lesions, an MTV threshold of 0.5 had a sensitivity of 85.0%, specificity of 47.1%, positive predictive value of 79.1%, negative predictive value of 57.1%, and accuracy of 73.7%. The presence of adjacent soft tissue involvement around rib lesions showed a significant association with malignancy (odds ratio = 6.750; 95% CI, 1.837-24.802, P = .003).

CONCLUSIONS

The MTV is a useful PET/CT parameter for assisting in the differential diagnosis of suspected malignant lesions of the ribs. CT finding of adjacent soft tissue involvement around rib was significantly associated with malignant lesions of the ribs.

Various recurrence dynamics for non-small cell lung cancer depending on pathological stage and histology after surgical resection

Background

Although there are numerous postoperative surveillance guidelines for non-small cell lung cancer (NSCLC), most guidelines recommend the same protocol for patients with different recurrence dynamics. In this study, we investigated the recurrence dynamics of NSCLC patients according to their clinical factors.

Methods

We retrospectively reviewed the data from NSCLC patients who underwent complete resection between 2007 and 2017. Recurrence dynamics were estimated using the hazard rate and displayed with kernel smoothing method according to tumor stage, sex, and histology.

Results

During the period, a total of 6,012 patients were enrolled: 3,687 (61.3%) in stage I, 1,194 (19.9%) in stage II, and 1,131 (18.8%) in stage III. The highest recurrence hazard rate was shown at about 12 months, regardless of tumor stage, but the maximum of hazard rate for stage III was 7 times higher than that in stage I. Depending on tumor histology, the highest peak of hazard curve was observed at different periods, 9 months in squamous cell carcinoma and 15 months in adenocarcinoma. These trends were similar when analyzed based on sex, 9 months in male patients and 15 months in female patients. In stage I adenocarcinoma, recurrence hazard rates were significantly different depending on histologic subtypes and tumor differentiation grade.

Conclusions

Adopting the same follow-up strategy may be undesirable in NSCLC patients who have different clinical and pathological characteristics. Adequate consideration of these factors will help clinicians develop detailed follow-up strategy in lung cancer patients with different recurrence dynamics.

Parsimonious risk model for predicting mortality after surgical lung biopsy for interstitial lung disease

OBJECTIVES

To develop a risk model for predicting postoperative mortality and morbidity in patients with interstitial lung disease undergoing surgical lung biopsy.

METHODS

From 2004 to 2019, patients who underwent surgical lung biopsy for interstitial lung disease were included in this study. Based on the findings of the multivariable analysis using preoperative clinical variables, a risk model for predicting postoperative mortality and morbidity was developed.

RESULTS

During the study period, 1177 patients were enrolled. Among them, morbidity and mortality occurred in 45 (3.8%) and 29 (2.5%) patients, respectively, which gradually declined over time from 8.9% in 2004-2005 to 0% in 2018-2019. In the final multivariable analysis, the dyspnoea grade, a forced vital capacity of ≤ 60%, preoperative oxygen therapy, and preoperative intensive care unit stay were found to be the independent factors associated with both morbidity and mortality; smoking> 40 pack-years was additionally identified as a factor related to mortality. Diffusing capacity of carbon monoxide ≤ 50%, which was a significant factor in the univariable analysis, became insignificant after adjustment for the forced vital capacity in the multivariable analysis. The risk scoring system based on this model showed a good discriminant ability for both morbidity (area under the receiver operating characteristic curve [95% confidence interval]: 0.830 [0.726-0.932]) and mortality (0.887 [0.804-0.975]).

CONCLUSIONS

We developed a scoring system for predicting the risk of morbidity and mortality, which could help determine surgical candidates for lung biopsy among patients with interstitial lung disease.

Tumor regression grade combined with lymph node status in esophageal squamous cell carcinoma after neoadjuvant chemoradiotherapy

Introduction

We aimed to elucidate the prognostic value of tumor regression grade (TRG) combined with lymph node status compared with the 8th edition of the ypTNM staging system in patients with advanced esophageal squamous cell cancer (ESCC) after neoadjuvant chemoradiotherapy (nCRT).

Methods

We enrolled 325 patients with ESCC who underwent nCRT followed by complete resection. We adopted the modified Schneider TRG system, with high (ypT0N0), mid (ypT0N+ or ypT + N0), and low (ypT + N+). After developing a multivariable Cox model, the discrimination ability of the ypStage and TRG systems was evaluated using the Akaike Information Criterion (AIC) and R² measure.

Results

The mean duration of follow‐up was 56.7 ± 43.3 months. The survival curves between the adjacent groups of TRG were significantly different for both overall survival (OS) and recurrence‐free survival (RFS). However, there were no significant differences between ypStages II and III for OS (p = 0.683) or RFS (p = 0.760). The TRG system also had a discrimination ability in patients with ypStage I (p < 0.001 for both OS and RFS) and ypStage III (p = 0.045 for OS and 0.042 for RFS). Compared with the ypTNM staging system, the modified TRG had a lower AIC value (1835.99 vs. 1852.02) and a higher R² (0.256 vs. 0.177), indicating better discrimination ability and prediction accuracy.

Conclusions

For patients with ESCC who underwent esophagectomy following nCRT, the modified Schneider TRG system may complement the ypStage and help clinicians select the most appropriate postoperative treatment and surveillance.

An Overview of Surgical Treatment of Thymic Epithelial Tumors in Korea: A Retrospective Multicenter Analysis

Background

Thymic epithelial tumors (TETs) are rare, and information regarding their surgical outcomes and prognostic factors has rapidly changed in the past few decades. We analyzed surgical treatment practices for TETs and outcomes in terms of overall survival (OS) and freedom from recurrence (FFR) during a 13-year period in Korea.

Methods

In total, 1,298 patients with surgically resected TETs between 2000 and 2013 were enrolled retrospectively. OS and FFR were calculated using the Kaplan-Meier method and evaluated with the log-rank test. Prognostic factors for OS and FFR were analyzed with multivariable Cox regression.

Results

A total of 1,098 patients were diagnosed with thymoma, and 200 patients were diagnosed with thymic carcinoma. Over the study period, the total number of patients with surgically treated TETs and the proportion of patients who underwent minimally invasive thymic surgery (MITS) increased annually. The 5-year and 10-year survival rates of surgically treated TETs were 91.0% and 82.1%, respectively. The 5-year and 10-year recurrence rates were 86.3% and 80.0%, respectively. The outcomes of surgically treated TETs improved over time. Multivariable Cox hazards analysis for OS, age, tumor size, and Masaoka-Koga stage were independent predictors of prognosis. The World Health Organization classification and tumor-node-metastasis (TNM) staging were also related to the prognosis of TETs.

Conclusion

Surgical treatment of TETs achieved a good prognosis with a recent increase in MITS. The M-K stage was the most important prognostic factor for OS and FFR. The new TNM stage could also be an effective predictor of the outcomes of TETs.

Nuss Procedure for Surgical Stabilization of Anterior Flail Chest with Mechanical Ventilation Weaning Failure: A Case Report

Flail chest is a critical medical condition in which multiple segmentally fractured adjacent ribs cause paradoxical movement of the thoracic cage in patients with severe blunt trauma injury. Surgical stabilization is considered essential in patients who require mechanical ventilation. However, there is no consensus on which surgical procedure to choose among the various available techniques or when to perform surgery. We report the case of a patient with traumatic anterior flail chest due to bilateral multiple fractures of the ribs requiring surgical stabilization in whom weaning from mechanical ventilation had failed. The Nuss procedure using double bars with the bridge technique was performed for chest wall stabilization. The patient was weaned from mechanical ventilation on postoperative day 44 and she underwent bar removal on postoperative day 71. After extensive rehabilitation for multiple trauma, she was discharged successfully. The patient currently shows no recurrence of chest wall depression in outpatient follow-up.

Predicting Postoperative Complications and Long-Term Survival After Lung Cancer Surgery Using Eurolung Risk Score

BACKGROUND

This study aimed to assess the clinical relevance of the parsimonious Eurolung risk scoring system for predicting postoperative morbidity, mortality, and long-term survival in Korean patients with surgically resected non-small cell lung cancer.

METHODS

This retrospective analysis used the data of patients who underwent anatomical resection for non-small cell lung cancer between 2004 and 2018 at a single institution. The parsimonious aggregate Eurolung score was calculated for each patient. The Cox regression model was used to determine the ability of the Eurolung scoring system for predicting long-term outcomes.

RESULTS

Of the 7,278 patients in the study, cardiopulmonary complications and mortality occurred in 687 (9.4%) and 53 (0.7%) patients, respectively. The rate of cardiopulmonary complications and mortality gradually increased with the increase in the Eurolung risk scores (all P < 0.001). When risk scores were grouped into four categories, the Eurolung scoring system showed a stepwise deterioration of overall survival with the increase in risk scores, and this association was statistically significant (P < 0.001). Multivariate Cox analysis showed that the Eurolung scoring system, classified into four categories, was a significant prognostic factor of overall survival even after adjusting for covariates such as tumor histology and pathological stage (P < 0.001).

CONCLUSION

Stratification based on the parsimonious Eurolung scoring system showed good discriminatory ability for predicting postoperative morbidity, mortality, and long-term survival in South Korean patients with surgically resected non-small cell lung cancer. This might help clinicians to provide a detailed prognosis and decide the appropriate treatment option for high-risk patients with non-small cell lung cancer.

Preoperative electromagnetic navigation bronchoscopy-guided one-stage multiple-dye localization for resection of subsolid nodules: A single-center pilot study

Background

Electromagnetic navigation bronchoscopy (ENB)‐guided transbronchial dye marking and video‐assisted thoracoscopic surgery (VATS) is an emerging technique that enables successful resection of multiple small subsolid pulmonary nodules. The aim of this study was to evaluate the accuracy and safety of preoperative ENB‐guided transbronchial multiple dye localization for VATS resection of subsolid pulmonary nodules.

Methods

As a single‐center pilot study, we recruited patients with at least two small or subsolid pulmonary nodules. Multiple‐dye localization was performed by intraoperative ENB‐guided transbronchial injection of an indigo carmine dye. The patients underwent VATS for sublobar resection immediately after localization. The accuracy of ENB‐guided dye marking was checked.

Results

ENB‐guided one‐stage multiple dye localization was conducted for 18 pulmonary nodules in seven patients between September 2018 and December 2019. The mean diameter of the pulmonary nodules was 9.3 mm (range, 4–18) and the mean distance from the pleura to pulmonary nodule was 6 mm (range, 1–17 mm). ENB‐guided transbronchial multiple dye localization was successfully performed in 94.4% (17/18), and the accuracy of ENB‐guided dye marking was 88.2% (15/17). When two nodules were not seen in intraoperative fields, anatomical sublobar resection was performed. There was no conversion to thoracotomy and operative mortalities. Among the seven patients, only one patient showed mild intrabronchial bleeding but stopped spontaneously. The changes in lung function after multiple wedge resections (−1.6% to 24.8%) were tolerable level.

Conclusions

ENB‐guided one‐stage transbronchial dye localization showed accurate and safe intraoperative identification of multiple subsolid pulmonary nodules. A large scale prospective clinical study is warranted.

Natural Progression of Ground-glass Nodules after Curative Resection for Non-small Cell Lung Cancer

BACKGROUND

This retrospective study investigated the natural course of synchronous ground-glass nodules (GGNs) that remained after curative resection for non-small-cell lung cancer (NSCLC).

METHODS

Prospectively collected retrospective data were reviewed concerning 2,276 patients who underwent curative resection for NSCLC between 2008 and 2017. High-resolution computed tomography or thin-section computed tomography data of 82 patients were included in the study. Growth in size was considered the most valuable outcome, and patients were grouped according to GGN size change. Patient demographic data (e.g., age, sex, and smoking history), perioperative data (e.g., GGN characteristics, histopathology and pathological stage of the resected tumours), and other medical history were evaluated in a risk factor analysis concerning GGN size change.

RESULTS

The median duration of follow-up was 36.0 months (interquartile range, 23.0-59.3 months). GGN size decreased in 6 patients (7.3%), was stationary in 43 patients (52.4%), and increased in 33 patients (40.2%). In univariate analysis, male sex, the GGN size on initial CT, part-solid GGN and smoking history (≥ 10 pack-years) were significant risk factors. Among them, multivariate analysis revealed that lager GGN size, part-solid GGN and smoking history were independent risk factors.

CONCLUSION

During follow-up, 40.2% of GGNs increased in size, emphasising that patients with larger GGNs, part-solid GGN or with a smoking history should be observed.

Clinical Significance of Regional Lymph Node Evaluation during Sublobar Resection in Lung Cancer

BACKGROUND

This study evaluated the prognostic effect of regional lymph node evaluation (LNE) in patients with non-small cell lung cancer (NSCLC) who underwent sublobar resection based on harvested node stations.

METHODS

We retrospectively reviewed the data of patients with NSCLC who underwent sublobar resection at Asan Medical Center between 2007-2016. To adjust for the differences in confounding variables between the groups, propensity score-based inverse probability of treatment weighting (IPTW) was performed.

RESULTS

In the LNE group with pathological N0 disease (n = 522), 458 (87.7%) patients underwent both N1 and N2 LNE (N1 + N2 group) and 64 (12.3%) underwent only N2 LNE (N2 alone group). The N1 + N2 group had better prognosis before (p < 0.001) and after IPTW adjustment (p = 0.019). Similar results were obtained even in patients with tumor size ≤ 2 cm (p = 0.032) or who underwent wedge resection (p = 0.041). According to IPTW-adjusted multivariable analysis, the performance of regional LNE was a significant prognostic factor for survival outcome (hazard ratio [95% confidence interval] = 0.45 [0.27-0.74], p = 0.002).

CONCLUSIONS

LNE is a critical process during sublobar resection in patients with NSCLC. Regional LNE during sublobar resection can significantly affect clinical outcomes even in patients with wedge resection or with tumor size < 2 cm.

Right Ventricular Assist Device With Extracorporeal Membrane Oxygenation for Bridging Right Ventricular Heart Failure to Lung Transplantation: A Single-Center Case Series and Literature Review

OBJECTIVE

Right ventricular heart failure (RVHF) is a critical complication in patients with respiratory failure, particularly among those who transitioned to lung transplantation using venovenous (VV) extracorporeal membrane oxygenation (ECMO). In these patients, both cardiac and respiratory functions are supported using venoarterial or venoarterial-venous ECMO. However, these modalities increase the risk of device-related complications, such as thromboembolism, bleeding, and limb ischemia, and they may disturb early rehabilitation. Due to these limitations, a right ventricular assist device with an oxygenator (Oxy-RVAD) using ECMO may be considered for patients with RVHF with VV ECMO.

DESIGN

A retrospective case series and literature review.

SETTING

A single tertiary care university hospital.

PARTICIPANTS

The study comprised lung transplantation candidates on ECMO bridging who developed right-sided heart failure.

INTERVENTIONS

An RVAD with ECMO.

MEASUREMENTS AND MAIN RESULTS

Of eight patients who underwent the study protocol, seven were bridged successfully to lung transplantation (BTT), and all patients with BTT were discharged, with a 30-day survival rate of 100% (7/7 patients). The 180-day survival rate was 85% (6/7 patients).

CONCLUSIONS

The study suggested that Oxy-RVAD using ECMO may be a viable option for bridging patients with RVHF to lung transplantation.

TRIAL REGISTRATION

Retrospectively registered.

Lobe-specific lymph node dissection in stage IA non-small-cell lung cancer: a retrospective cohort study

OBJECTIVES

To investigate lymph node (LN) metastasis according to tumour location and assess the impact of lobe-specific LN dissection on survival in stage IA non-small-cell lung cancer (NSCLC).

METHODS

We retrospectively analysed the data of patients with clinical stage IA NSCLC treated with lobectomy and systematic LN dissection at Asan Medical Center (Seoul, Korea) between June 2005 and April 2017. Patients who received neoadjuvant therapy had multiple primary tumours or missed the follow-up during the first postoperative year were excluded. The patients were divided into five groups according to involved lung lobes: right upper lobe (RUL), right middle lobe (RML), right lower lobe (RLL), left upper lobe (LUL) and left lower lobe (LLL), which were further divided into subgroups according to LN station metastasis. Overall survival (OS) and the incidence of metastasis were calculated for each subgroup. Efficacy indices (EIs) were calculated to determine the correlation between each lung lobe and LN station, and the impact of the dissection of these stations on survival.

RESULTS

A total of 1202 patients were analysed. The 5-year OS in the RUL, RML, RLL, LUL and LLL groups was 74%, 88%, 78%, 80% and 75%, respectively. The incidence of single LN station metastasis was 11%, 10%, 10%, 16% and 14%, respectively. The lobe-specific LNs for RUL, RML, RLL, LUL and LLL were stations 2/3/4, 4/7, 2/4/7, 4/5/6 and 6/7/9, respectively. Moreover, the LN stations with high EIs for RUL, RML, RLL, LUL and LLL were 4, 7, 7, 5 and 7, respectively. In the RUL group, the incidence of metastasis to stations 2, 3 and 4 was 2.3%, 0.5% and 7.6%, and the EI was 0.8, 0.3 and 4.3, respectively. In RML, the incidence of metastasis to stations 4 and 7 was 4% and 6%, and the EI was 1.3 and 2.4, respectively. In RLL, the incidence of metastasis to stations 2, 4 and 7 was 4.4%, 5.6% and 8.3%, and the EI was 1.3, 1.4 and 3.3, respectively. In LUL, the incidence of metastasis to stations 4, 5 and 6 was 1.4%, 11.8% and 2.5%, and the EI was 0.4, 7.1 and 0.5, respectively. In LLL, the incidence of metastasis to stations 6, 7 and 9 was 1.1%, 5.7% and 1.7%, and the EI was 0.6, 2.3 and 0.5, respectively. Furthermore, the OS of patients with lobe-specific LN metastasis was statistically significantly different from that of the non-lobe-specific LN metastasis group with P-values of <0.001 for RUL, 0.002 for RML, 0.002 for RLL, 0.001 for LUL and 0.003 for LLL.

CONCLUSIONS

Our findings support the use of lobe-specific LN dissection in stage IA NSCLC. When LN stations with high EI were negative, LN metastasis in other stations was unlikely. The incidence of LN metastasis beyond lobe-specific LN stations was ∼1% in all subgroups. Dissection of non-lobe-specific LNs may not improve the OS; however, prospective randomized controlled trials are needed to modify the standard approach.

Effects of the duration of bridge to lung transplantation with extracorporeal membrane oxygenation

Background

Although bridge to lung transplantation (BTT) with extracorporeal membrane oxygenation (ECMO) is increasingly performed, the impact of BTT and its duration on post-transplant outcomes are unclear.

Methods

We retrospectively reviewed medical records of adult patients who underwent lung or heart-lung transplantation in our institution between January 2008 and December 2018. Data were compared in patients who did (n = 41; BTT) and did not (n = 36; non-BTT) require pre-transplant ECMO support. Data were also compared in patients who underwent short-term (<14 days; n = 21; ST-BTT) and long-term (≥14 days; n = 20; LT-BTT) BTTs.

Results

Among 77 patients included, 51 (66.2%) were male and median age was 53 years. The median bridging time in the BTT group was 13 days (interquartile range [IQR], 7–19 days). Although simplified acute physiologic score II was significantly higher in the BTT group (median, 35; IQR, 31–49 in BTT group vs. median, 12; IQR, 7–19 in non-BTT group; p<0.001), 1-year (73.2% vs. 80.6%; p = 0.361) and 5-year (61.5% vs. 61.5%; p = 0.765) post-transplant survival rates were comparable in both groups. Comparison of ST- and LT-BTT subgroups showed that 1-year (90.5% vs. 55.0%; p = 0.009) and 5-year (73.0% vs. 48.1%; p = 0.030) post-transplant survival rates were significantly higher in ST-BTT group. In age and sex adjusted model, the LT-BTT was an independent risk factor for 1-year post-transplant mortality (hazard ratio, 3.019; 95% confidence interval, 1.119–8.146; p = 0.029), whereas the ST-BTT was not.

Conclusions

Despite the severe illness, the BTT group showed favorable post-transplantation outcomes, particularly those bridged for less than 14 days.

The Prognostic Value of Programmed Death-ligand 1 (PD-L1) in Patients who Received Neoadjuvant Chemoradiation Therapy Followed by Surgery for Locally Advanced Non-small Cell Lung Cancer

BACKGROUND/AIM

We analyzed the prognostic efficacy of programmed death-ligand 1 (PD-L1) in locally advanced non-small cell lung cancer (LA-NSCLC) patients.

PATIENTS AND METHODS

During 2005-2016, 211 patients underwent neoadjuvant concurrent chemoradiation therapy (CCRT) followed by surgical resection for LA-NSCLC at Asan Medical Center. PD-L1 expression and CD8+ tumor-infiltrating lymphocytes (TIL) were measured pre- and post-neoadjuvant CCRT and analyzed using immuno - histochemical staining.

RESULTS

In total, 39 patients were enrolled. Overall survival (OS) and disease-free survival (DFS) were significantly longer in patients with increased PD-L1 expression and increased CD8+ TIL density post-neoadjuvant CCRT. Univariate Cox regression analysis confirmed that increased levels of PD-L1 and increased CD8+ TIL density were prognostic factors for OS and DFS. Multivariate Cox regression analysis confirmed that increased levels of PD-L1 was a prognostic factor for OS and increased CD8+ TIL density for DFS.

CONCLUSION

Relative changes in PD-L1 expression post-neoadjuvant CCRT can be utilized to predict the prognosis of LA-NSCLC patients.

Long-term outcomes of upfront surgery in patients with resectable pathological N2 non-small-cell lung cancer

OBJECTIVES

Although the standard treatment for pathological N2 (pN2) non-small-cell lung cancer (NSCLC) patients is definitive chemoradiation, surgery can be beneficial for resectable pN2 disease. Herein, we report the long-term clinical outcomes of upfront surgery followed by adjuvant treatment for selected patients with resectable pN2 disease.

METHODS

We performed a retrospective analysis of clinical outcomes for patients with pN2 disease who underwent surgery as the first-line therapy. Multivariable Cox regression analysis was used to identify the significant factors for overall survival (OS) and recurrence-free survival.

RESULTS

From 2004 to 2015, a total of 706 patients with pN2 NSCLC underwent complete anatomical resection at our institution. The patients' clinical N stages were cN0, 308 (43.6%); cN1, 123 (17.4%) and cN2, 275 (39.0%). Adjuvant chemotherapy, radiotherapy and chemoradiotherapy were administered to 169 (23.9%), 115 (17.4%) and 299 patients (42.4%), respectively. With a median follow-up of 40 months, the respective median time and 5-year rate of OS were 52 months and 44.7%. According to subdivided pN2 descriptors, the median OS time was 80, 53 and 37 months for patients with pN2a1, pN2a2 and pN2b, respectively. Adjuvant chemotherapy was a significant prognostic factor for both OS [hazard ratio (HR) 0.39, 95% confidence interval (CI) 0.28-0.52; P < 0.001] and recurrence-free survival (HR 0.42, 95% CI 0.30-0.58; P < 0.001).

CONCLUSIONS

Upfront surgery followed by adjuvant therapy for resectable N2 disease showed favourable outcomes compared to those reported in previous studies. Adjuvant chemotherapy is essential to improve the prognosis for patients undergoing upfront surgery for N2 disease.

Case of a 21-Year-Old Man With Hemoptysis, Recurrent Pneumothorax, and Cavitary Lung Lesions

CASE PRESENTATION

A 21-year-old man was admitted to our hospital with recurrent bilateral pneumothorax and hemoptysis. Three years earlier, he underwent coil embolization due to a subarachnoid hemorrhage caused by an intracerebral aneurysm rupture. Two months after the coil embolization, he underwent an emergent total colectomy due to a massive infarction of the colon. One year after the colectomy, he started to have recurrent hemoptysis, and a few months later, multiple episodes of bilateral pneumothorax that required a chest tube placement began to occur. Notably, he had a history of easy bruising. He was taking Depakote and aspirin to prevent seizure and thromboembolic complications, respectively, both of which he began taking after the coil embolization. He denied the use of any illicit drugs. The histories of his parents and sister were not remarkable.

Surgical Outcome of Pulmonary Metastasectomy for Hepatocellular Carcinoma Recurrence in Liver Transplant Patients

Background

Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) results in poor survival outcome. This study assessed the clinical outcomes of pulmonary metastasectomy in LT recipients with pulmonary metastasis of HCC in a high-volume transplant center and analyzed factors prognostic of survival following metastasectomy.

Material/Methods

This study analyzed outcomes in 52 patients who underwent pulmonary resection due to pulmonary metastasis as the first recurrence of HCC after LT from January 2004 to December 2017 in a single center.

Results

The 52 enrolled patients included 46 men and 6 women, aged 56.0±6.6 years. Their 1-, 3-, and 5-year survival rates after pulmonary resection were 75.0%, 43.5%, and 33.9%, respectively. The 1-, 3-, and 5-year survival rates were 85.3%, 47.1%, and 34.2%, respectively, in patients with further metastases and 55.6%, 38.1%, and 38.1%, respectively, in patients without further metastases (P=0.45). The size and number of pulmonary metastatic nodules were unrelated to survival rates (all P>0.10). A shorter recurrence-free period after LT (hazard ratio [HR]=0.553, P=0.006), elevated alpha-fetoprotein concentration at metastasectomy (HR=2.142, P=0.03), and adjuvant chemotherapy after metastasectomy (HR=3.79, P=0.003) were independent risk factors for survival after metastasectomy.

Conclusions

Pulmonary metastasectomy for HCC recurrence in LT recipients showed favorable survival outcomes. Independent risk factors for survival after metastasectomy included recurrence-free survival after LT, alpha-fetoprotein level at metastasectomy, and adjuvant chemotherapy after metastasectomy.

Experience of International Air Transportation and Subsequent Lung Transplant in a Patient with COVID-19-associated Acute Respiratory Distress Syndrome: a Case Report

We report an inspiring case of a 55-year-old Korean female diagnosed with coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (ARDS) in Mexico. The patient was assessed for lung transplant as a salvage therapy for treatment-refractory ARDS following no signs of clinical improvement for > 7 weeks, despite best treatment. The patient was transported from Mexico to Korea by air ambulance under venovenous extracorporeal membrane oxygenation (ECMO) support. She was successfully bridged to lung transplant on day 88, 49 days after the initiation of ECMO support. ECMO was successfully weaned at the end of operation, and no bleeding or primary graft dysfunction was observed within the first 72 hours. The patient was liberated from mechanical ventilation on postoperative day 9 and transferred to the general ward 5 days later. Despite the high doses of immunosuppressants, there was no evidence of viral reactivation after transplant. At 3 months post-transplantation, she was discharged to home without complication. Our experience suggests that successful lung transplant for COVID-19-associated ARDS is feasible even in a patient with prolonged pre-transplant ECMO support. Lung transplant may be considered a salvage therapy for COVID-19-associated ARDS that does not respond to conventional treatments.

The addition of radiotherapy to adjuvant chemotherapy has a combinatorial effect in pN2 non-small cell lung cancer only with extranodal invasion or multiple N2 metastasis

OBJECTIVES

The benefit of adjuvant therapy for heterogenous group of pathological N2 (pN2) non-small cell lung cancer (NSCLC) remains unclear. We evaluated the prognostic effect of adjuvant therapy after stratifying patients with pN2 according to subdivided N2 descriptors.

MATERIALS AND METHODS

We performed a retrospective analysis of clinical outcomes in patients with pN2 NSCLC who underwent upfront surgery. N2 descriptors were subdivided as single N2 metastasis without N1 involvement (pN2a1), single N2 with metastasis with N1 involvement (pN2a2), and multiple N2 metastasis (pN2b).

RESULTS

From 2005-2017, 838 patients with pN2 NSCLC underwent complete resection. There were 173 (21.0 %), 338 (40.3 %), and 324 (38.7 %) in the pN2a1, pN2a2, and pN2b groups. Patients who received chemoradiotherapy (CRTx; n = 389, 46.4 %) or chemotherapy (CTx; n = 204, 24.3 %) had similar prognoses, which were better than prognoses in patients who received with radiotherapy (RTx; n = 116, 13.8 %) or those who did not receive adjuvant therapy (n = 129, 15.4 %). According to the stratified multivariable Cox analysis, patients with pN2b stage in the CTx group had a significantly poor prognosis than those in the CRTx group (hazard ratio, 1.38; 95 % confidence interval, 1.03-1.98; p = 0.046). The difference in survival outcomes between the CRTx and CTx groups was significant in patients with extranodal invasion (ENI) (p = 0.011), but not in those without ENI (p = 0.527) CONCLUSIONS: Adjuvant CTx improves the overall and recurrence-free survival in patients with pN2 NSCLC undergoing upfront surgery with complete resection. RTx with adjuvant chemotherapy has a combinatorial effect on pN2 NSCLC only with ENI or multiple N2 metastasis.

Successful Lobar Lung Transplant From a Marginal Deceased Donor With a History of Treated Pulmonary Tuberculosis: A Case Report

The shortage of available donor lungs is a continuing clinical problem. Lobar lung transplant and the extension of donor lung criteria may expand the pool of donor lungs. We here report a case of lobar lung transplant from a marginal deceased donor with bronchiectasis and fibrosis at the left upper lobe and a history of treated pulmonary tuberculosis. Our experience with this case suggests that a lobar lung transplant can be considered not only for size mismatches but also for use of locally damaged lungs. In addition, lungs from a donor who received treatment for pulmonary tuberculosis may be feasible for transplant with chemoprophylaxis for latent tuberculosis infection. Our current case indicates one possible option to overcome the persistent shortage of available donor lungs.

A Validation Study of the Recommended Change in Residual Tumor Descriptors Proposed by the International Association for the Study of Lung Cancer for Patients With pN2 NSCLC

INTRODUCTION

This study aimed to validate the residual tumor (R) descriptors proposed by the International Association for the Study of Lung Cancer (IASLC) for patients with pathologic N2 (pN2) NSCLC.

METHODS

We retrospectively reviewed the data of patients with pN2 NSCLC who underwent anatomical resection during the period 2004 to 2018. The R status classified using the Union for International Cancer Control (UICC) criteria was compared with that reassigned using the IASLC criteria. Survival analysis was performed using Cox proportional hazards models to assess the prognostic significance of IASLC R descriptors.

RESULTS

Among 1039 patients, 91.1%, 8.1%, and 0.8% of the patients respectively received complete resection (R0), R1, and R2 defined using the UICC criteria, whereas 41.6%, 20.4%, and 38% respectively received R0, uncertain resection (R[un]), and R1/2 resection defined using the IASLC criteria. Furthermore, 206 patients (21.8%) were reclassified from having UICC R0 to having IASLC R(un) mainly owing to the highest mediastinal lymph node involvement (89.8%). Owing to extracapsular extension, 309 patients (32.6%) with UICC R0 were reclassified as having IASLC R1/2. Patients with IASLC R(un) had significantly worse and better prognosis than those with IASLC R0 and IASLC R1/2, respectively. In multivariable analysis, the prognostic difference between IASLC R0 and R(un) was similar after adjustment for subdivided N2 descriptors including pN2a1, pN2a2, and pN2b.

CONCLUSIONS

Along with subdivided N descriptors, detailed R descriptors proposed on the basis of the IASLC criteria can ensure optimal staging, enabling the most appropriate decision-making on adjuvant therapy for patients with pN2 NSCLC.

Surgical outcomes of pulmonary metastasectomy in hepatocellular carcinoma patients according to approach method: thoracoscopic versus open approach

Background

The role of surgical intervention as a treatment for pulmonary metastasis (PM) from hepatocellular carcinoma (HCC) has not been established. In this study, we investigated the clinical outcomes of pulmonary metastasectomy. Using propensity score matching (PSM) analysis, we compared the results according to the surgical approach: video-assisted thoracic surgery (VATS) versus the open method.

Methods

A total of 134 patients (115 men) underwent pulmonary metastasectomy for isolated PM of HCC between January 1998 and December 2010 at Seoul Asan Medical Center. Of these, 84 underwent VATS (VATS group) and 50 underwent thoracotomy or sternotomy (open group). PSM analysis between the groups was used to match them based on the baseline characteristics of the patients.

Results

During the median follow-up period of 33.4 months (range, 1.8–112.0), 113 patients (84.3%) experienced recurrence, and 100 patients (74.6%) died of disease progression. There were no overall survival rate, disease-free survival rate, and pulmonary-specific disease-free survival rate differences between the VATS and the open groups (p = 0.521, 0.702, and 0.668, respectively). Multivariate analysis revealed local recurrence of HCC, history of liver cirrhosis, and preoperative alpha-fetoprotein level as independent prognostic factors for overall survival (hazard ratio, 1.729/2.495/2.632, 95% confidence interval 1.142–2.619/1.571–3.963/1.554–4.456; p = 0.010/< 0.001/< 0.001, respectively).

Conclusions

Metastasectomy can be considered a potential alternative for selected patients. VATS metastasectomy had outcomes comparable to those of open metastasectomy.

Sequential ubiquitination of p53 by TRIM28, RLIM, and MDM2 in lung tumorigenesis

Tripartite motif-containing 28 (TRIM28) is an E3 ubiquitin ligase harboring multiple cellular functions. We found that the TRIM28 protein is frequently overexpressed in patients with lung cancer. The stable overexpression of TRIM28 in lung cancer cells and xenograft models significantly increased the proliferation, migration, and invasiveness, whereas knockdown of TRIM28 had the opposite effect. We further observed that TRIM28 regulates the ubiquitin ligases RLIM and MDM2 to target the p53 levels during lung tumorigenesis. These data provide new insights into lung cancer development and potential new therapeutic targets for this disease.

The role of postoperative radiotherapy in stage II and III thymoma: a Korean multicenter database study

Background

Complete resection is a standard treatment for patients with Masaoka-Koga stages II and III thymoma, however the role of postoperative radiotherapy (PORT) is controversial. We analyzed data collected from 4 Korean hospitals to determine the effectiveness of PORT in stage II and III thymoma patients.

Methods

Between January 2000 and December 2013, 1,663 patients underwent surgery for thymic tumors at the 4 hospitals. Among them, 668 patients (527 with stage II and 141 with stage III) were investigated, among whom, 443 received PORT (335 with stage II and 108 with stage III). Propensity score matching (PSM) was performed, and 404 patients (346 with stage II and 58 with stage III) were selected.

Results

Perioperative characteristics were similar in the PORT and non-PORT groups after PSM. On survival analysis of stage II patients, the PORT and non-PORT groups showed no difference in either 5-year recurrence-free survival (RFS) (96.3% vs. 96.6%, P=0.622) or 5-year overall survival (OS) (94.6% vs. 93.8%, P=0.839). However, among stage III patients, the PORT group showed significantly better 5-year RFS (75.7% vs. 50.1%, P=0.040) and 5-year OS (86.5% vs. 54.7%, P=0.001). On multivariate Cox regression analysis, PORT was a significant positive prognostic factor in terms of both RFS (P=0.005) and OS (P=0.004) in patients with stage III thymomas, but not in those with stage II disease (P=0.987 and 0.968, respectively).

Conclusions

PORT improved the RFS and OS in stage III thymoma patients, but showed no survival benefit in stage II patients.

Long-term outcomes of video-assisted thoracoscopic lobectomy for clinical N1 non-small cell lung cancer: A propensity score-weighted comparison with open thoracotomy

OBJECTIVES

Although the video-assisted thoracic surgery (VATS) approach has been accepted as a safe and effective alternative to lobectomy, its advantage remains unclear in advanced-stage lung cancer. This study is aimed to evaluate the feasibility and long-term outcomes of VATS in lung cancer with clinical N1 (cN1) disease.

MATERIALS AND METHODS

We retrospectively reviewed the records of 1149 consecutive patients who underwent lobectomy for cN1 disease from 2006 to 2016. Perioperative outcomes and long-term survival rates were compared using a propensity score-based inverse probability of treatment weighting (IPTW) technique.

RESULTS

We performed VATS and open thoracotomy for 500 and 649 patients, respectively. All preoperative characteristics became similar between the two groups after IPTW adjustment. Compared to thoracotomy, VATS was associated with shorter hospitalization (7.7 days vs. 9.2 days, p < 0.001), earlier adjuvant chemotherapy (41.7 days vs. 46.6 days, p = 0.028), similar complete resection rates (95.2 % vs. 94.0 %, p = 0.583), and equivalent dissected lymph nodes (27.5 vs. 27.8, p = 0.704). On IPTW-adjusted analysis, overall survival (OS) (59.4 % vs. 60.3 %, p = 0.588) and recurrence-free survival (RFS) (59.2 % vs. 56.9 %, p = 0.651) at 5 years were also similar between the two groups. Multivariable Cox analysis revealed that VATS was not a significant prognostic factor for cN1 disease (p = 0.764 for OS and p = 0.879 for RFS).

CONCLUSIONS

VATS lobectomy is feasible for patients with cN1 disease, providing comparable perioperative outcomes, oncologic efficacy, and long-term outcomes as open thoracotomy.

Video-assisted thoracoscopic lobectomy is feasible for selected patients with clinical N2 non-small cell lung cancer

Few studies have evaluated the usefulness of video-assisted thoracoscopic surgery (VATS) for advanced-stage lung cancer. We aimed to evaluate the feasibility of VATS for treating clinical N2 (cN2) lung cancer. A retrospective cohort analysis was performed with data from 268 patients who underwent lobectomy for cN2 disease from 2007 to 2016. Using propensity score-based inverse probability of treatment weighting (IPTW), perioperative and long-term survival outcomes were compared. We performed VATS and open thoracotomy on 121 and 147 patients, respectively. Overall, VATS was preferred for patients with peripherally located tumors (p < 0.001). After IPTW-adjustment, all preoperative information became similar between the groups. Compared to thoracotomy, VATS was associated with shorter hospitalization (7.7 days vs. 9.1 days, p = 0.028), despite equivalent complete resection rates (92.6% vs. 90.5%, p = 0.488) and dissected lymph nodes (mean, 31.9 vs. 29.4, p = 0.100). On IPTW-adjusted analysis, overall survival (50.5% vs. 48.4%, p = 0.127) and recurrence-free survival (60.5% vs 44.6%, p = 0.069) at 5 years were also similar between the groups. Among selected patients with resectable cN2 disease and peripherally located tumors, VATS is feasible, associated with shorter hospitalization and comparable perioperative and long-term survival outcomes, compared with open thoracotomy.

Comparison of prognostic impact of lymphovascular invasion in stage IA non-small cell lung cancer after lobectomy versus sublobar resection: A propensity score-matched analysis

OBJECTIVES

Lymphovascular invasion (LVI) is a well-known poor prognostic factor after lobectomy for non-small cell lung cancer. However, the prognostic effect of LVI in patients who undergo sublobar resection has not been fully evaluated. Thus, we compared the prognostic impact of LVI in stage IA patients who underwent lobectomy or sublobar resection.

MATERIALS AND METHODS

We retrospectively reviewed the data from patients with stage IA NSCLC who underwent surgical resection between 2007 and 2016. The prognostic impact of LVI was calculated by the Cox proportional hazard regression model. To adjust for the differences in confounding variables between LVI-positive and LVI-negative patients, propensity score matching (PSM) was carried out in patients who underwent lobectomy or sublobar resection.

RESULTS

Among the stage IA NSCLC patients (n = 2134), 184 (8.6%) had been diagnosed with LVI, of whom 144 (8.9%) were in the lobectomy group (n = 1614) and 40 (7.7%) were in the sublobar resection group (n = 520). In multivariable analysis, LVI was a significant risk factor for both overall survival (OS) (hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.39-2.96; p < 0.001) and recurrence-free survival (RFS) (HR, 2.31; 95% CI, 1.68-3.17; p < 0.001). After PSM, the prognostic impact of LVI was greater in the sublobar resection group (HR = 4.93 and 4.25 for OS and RFS, respectively) than in the lobectomy group (HR = 1.77 and 2.51 for OS and RFS, respectively).

CONCLUSIONS

The presence of LVI was significantly associated with worse OS and RFS in stage IA NSCLC patients. The prognostic impact of LVI was more pronounced in the sublobar resection group than in the lobectomy group.

Comparative outcomes of robot-assisted minimally invasive versus open esophagectomy in patients with esophageal squamous cell carcinoma: a propensity score-weighted analysis

Robots are increasingly used in minimally invasive surgery. We evaluated the clinical benefits of robot-assisted minimally invasive esophagectomy (RAMIE) in comparison with the conventional open esophageal surgery. From 2012 to 2016, 371 patients with esophageal squamous cell carcinoma underwent an Ivor Lewis or McKeown procedure at our institution. Of these, 130 patients underwent laparoscopic gastric conduit formation followed by RAMIE, whereas 241 patients underwent conventional esophageal surgery, including laparotomy and open esophagectomy (OE). We compared the short- and long-term clinical outcomes of these patients using the propensity score-based inverse probability of treatment weighting technique (IPTW). Among the early outcomes, the OE group showed a higher incidence of pneumonia (P = 0.035) and a higher requirement for vasopressors (P = 0.001). Regarding the long-term outcomes, all-cause mortality was significantly higher (P = 0.001) and disease-free survival was lower (P = 0.006) in the OE group. Wound-related problems also occurred more frequently in the OE group (P = 0.020) during the long-term follow-up. There was no statistical intergroup difference in the recurrence rates (P = 0.191). The Cox proportional-hazard analysis demonstrated that wound problems (HR 0.16, 95% CI 0.02-0.57; P = 0.017), pneumonia (HR 0.23, 95% CI 0.06-0.68; P = 0.019), and use of vasopressors (HR 0.14, 95% CI 0.08-0.25; P = 0.001) were independent predictors of mortality. RAMIE could be a better surgical option for selected patients with esophageal squamous cell carcinoma.

Recent Trends in Demographics, Surgery, and Prognosis of Patients with Surgically Resected Lung Cancer in a Single Institution from Korea

BACKGROUND

Over the past few decades, demographics information has changed significantly in patients with surgically resected lung cancer. Herein, we evaluated the recent trends in demographics, surgery, and prognosis of lung cancer surgery in Korea.

METHODS

Patients with surgically resected primary lung cancer from 2002 to 2016 were retrospectively analyzed. Multivariable Cox regression analysis was conducted to identify prognostic factors for overall survival. The annual percent change (APC) and statistical significance were calculated using the Joinpoint software.

RESULTS

A total of 7,495 patients were enrolled. Over the study period, the number of lung cancer surgeries continued to increase (P < 0.05). The proportion of women to total subjects has also increased (P < 0.05). The proportion of elderly patients (≥ 70 years) as well as those with tumors measuring 1-2 cm and 2-3 cm significantly increased in both genders (all P < 0.05). The proportion of patients with adenocarcinoma, video-assisted thoracic surgery, sublobar resection, and pathological stage I significantly increased (P < 0.05). The 5-year overall survival rate of lung cancer surgery increased from 61.1% in 2002-2006 to 72.1% in 2012-2016 (P < 0.001). The operative period was a significant prognostic factor in multivariable Cox analysis (P < 0.001).

CONCLUSION

The mean age of patients with lung cancer surgery increased gradually, whereas tumor size reduced. Prognosis of lung cancer surgery improved with recent increases in the frequency of adenocarcinoma, video-assisted thoracic surgery, sublobar resection, and pathological stage I. The operation period itself was also an independent prognostic factor for overall survival.

Effect of medical thoracoscopy-guided intrapleural docetaxel therapy to manage malignant pleural effusion in patients with non-small cell lung cancer: A pilot study

Background

Although chemical pleurodesis is a useful treatment option for malignant pleural effusion, little is known about the effects of intrapleural docetaxel therapy.

Objectives

This study aimed to evaluate the effects of medical thoracoscopy‐guided intrapleural docetaxel therapy in patients with lung cancer.

Methods

Patients with lung cancer who diagnosed malignant pleural effusion were enrolled in this single‐center prospective pilot study. The clinical response and toxicity were evaluated at two, six and 12 weeks post‐treatment.

Results

Medical thoracoscopy‐guided intrapleural docetaxel therapy was conducted in four patients between June 2016 and August 2017. The control rate of malignant pleural effusion was 100% (4/4), and the progression‐free duration of effusion was 527 ± 109 days. No serious adverse events were observed, but only mild‐to‐moderate adverse events were observed and well controlled by conservative management. Although the overall quality of life assessed using questionnaires did not show significant improvement, symptom burden due to dyspnea was significantly improved.

Conclusions

Intrapleural docetaxel therapy with medical thoracoscopy showed good clinical responses, relieving dyspnea symptoms and providing tolerable safety profiles in patients with non‐small cell lung cancer (NSCLC) with malignant pleural effusion. A further prospective trial is warranted to evaluate the clinical effects of intrapleural docetaxel therapy in order to compare it with other treatment modalities.

Validation of the 8th edition of the TNM staging system in 3,950 patients with surgically resected non-small cell lung cancer

Background

The International Association for the Study of Lung Cancer introduced the 8th edition of the tumor, node, and metastasis (TNM) staging system for lung cancer. In this study, we validated the 8th edition of the TNM staging system and compared its discrimination power with that of the previous 7th edition.

Methods

A retrospective analysis was carried out on patients who underwent complete resection with systematic lymph node dissection for non-small cell lung cancer (NSCLC) between 2006 and 2015 at a tertiary referral center in Seoul, South Korea. Cox regression model was used to identify significant differences between adjacent TNM stage groupings. The Concordance index (C-index), Akaike Information Criterion (AIC), and R2 measure were utilized to evaluate the discrimination ability of the staging systems.

Results

A total of 3,950 patients (2,440 male, median age: 63 years) were analyzed. Median follow-up was 59 months (interquartile ranges, 38-88 months). According to the 8th edition, survival curves of overall survival (OS) and recurrence-free survival (RFS) within adjacent stage groupings showed significant differences except for IIA vs. IIB. Compared with the 7th edition, the 8th edition showed higher C-index (0.753 vs. 0.751), lower AIC (17,517 vs. 17,543), and higher R2 (0.178 vs. 0.171) values, indicating better discrimination ability.

Conclusions

Stratification based on the 8th edition of the TNM staging system showed favorable prognostic validity compared with the 7th edition. The 8th edition also had superior discrimination ability in terms of OS and RFS.

Right ventricular assist device with an oxygenator using extracorporeal membrane oxygenation as a bridge to lung transplantation in a patient with severe respiratory failure and right heart decompensation

Right heart decompensation is a fatal complication in patients with respiratory failure, particularly in those transitioned to lung transplantation using veno-venous extracorporeal membrane oxygenation (V-V ECMO). In these patients, veno-arterial (V-A ECMO) or veno-arterialvenous extracorporeal membrane oxygenation (V-AV ECMO) is used to support both cardiac and respiratory function. However, these processes may increase the risk of device-related complications such as bleeding, thromboembolism, and limb ischemia. In the present case, a 64-year-old male patient with idiopathic pulmonary fibrosis developed respiratory failure and commenced treatment with V-V ECMO as a bridge to lung transplantation. Unfortunately, the patient developed right heart decompensation and required both cardiac and respiratory support during treatment with V-V ECMO. Instead of adding arterial cannulation, he was switched to a novel configuration, a right ventricular assist device with an oxygenator (Oxy- RVAD) using ECMO, with drainage cannulation from the femoral vein and return cannulation to the main pulmonary artery. The patient was successfully bridged to lung transplantation without serious complications after 10 days of Oxy-RVAD support. To the best of our knowledge, this is an extreme rare and challenging case of Oxy-RVAD using ECMO in a patient successfully bridged to lung transplantation.

A nomogram for predicting recurrence after complete resection for thymic epithelial tumors based on the TNM classification: A multi-institutional retrospective analysis

OBJECTIVES

This study aimed to compare the predictive ability between the Masaoka-Koga (M-K) staging system and the 8th TNM staging system for the recurrence of thymic epithelial tumors (TETs). In addition, a nomogram was developed on the basis of the proposed TNM classification to predict individual recurrence rate.

METHODS

A retrospective study was performed on 445 patients who underwent complete resection (R0) of TETs between January 2000 and February 2013. Concordance index (C-index) was used as a statistical indicator to quantify the prediction power of the prediction models.

RESULTS

In multivariate analysis, tumor stage and WHO classification were independent recurrence factors in a predictive model on the basis of M-K and TNM stage. The TNM model showed higher C-index than the M-K model (0.837 vs 0.817). The nomogram, on the basis of the TNM model, revealed a highly predictive performance, with a bootstrap-corrected C-index of 0.85 (95% CI, 0.76 to 0.93).

CONCLUSIONS

A predictive model based on the 8th TNM stage was slightly better than that based on M-K stage with respect to recurrence after R0 of TETs. The proposed nomogram could be applied to estimate the individual recurrence rate and make decisions for proper surveillance.