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.

Two Cases of Robot-Assisted Totally Minimally Invasive Esophagectomy with Colon Interposition for Gastroesophageal Junction Cancer: Surgical Considerations.

This case report presents 2 patients with gastroesophageal junction cancer who both underwent totally minimally invasive esophagectomy with colon interposition. Patients 1 and 2, who were 43-year-old and 78-year-old men, respectively, had distinct clinical presentations and medical histories. Patient 1 underwent minimally invasive robotic esophagectomy with a laparoscopic total gastrectomy, colonic conduit preparation, and intrathoracic esophago-colono-jejunostomy. Patient 2 underwent completely robotic total gastrectomy, colon conduit preparation, and intrathoracic esophago-colono-jejunostomy. The primary challenge in colon interposition is assessing colon vascularity and ensuring an adequate conduit length, which is critical for successful anastomosis. In both cases, we used indocyanine green fluorescence angiography to evaluate vascularity. Determining the appropriate conduit is challenging; therefore, it is crucial to ensure a slightly longer conduit during reconstruction. Because totally minimally invasive colon interposition can reduce postoperative pain and enhance recovery, this surgical technique is feasible and beneficial.

Self-Assembled Oligopeptoplex-Loaded Dissolving Microneedles for Adipocyte-Targeted Anti-Obesity Gene Therapy.

Advancements in gene delivery systems are pivotal for gene-based therapeutics in oncological, inflammatory, and infectious diseases. This study delineates the design of a self-assembled oligopeptoplex (SA-OP) optimized for shRNA delivery to adipocytes, targeting obesity and associated metabolic syndromes. Conventional systems face challenges, including instability due to electrostatic interactions between genetic materials and cationic oligopeptides. Additionally, repeated injections induce discomfort and compromise patient well-being. To circumvent these issues, a dissolvable hyaluronic acid-based, self-locking microneedle (LMN) patch is developed, with improved micro-dose efficiency, for precise SA-OP delivery. This platform offers pain-free administration and improved SA-OP storage stability. In vitro studies in 3T3-L1 cells demonstrated improvements in SA-OP preservation and gene silencing efficacy. In vivo evaluation in a mice model of diet-induced type 2 diabetes yielded significant gene silencing in adipose tissue and a 21.92 ± 2.51% reduction in body weight with minimum relapse risk at 6-weeks post-treatment, representing a superior therapeutic efficacy in a truncated timeframe relative to the GLP-1 analogues currently available on the market. Additionally, SA-OP (LMN) mitigated insulin resistance, inflammation, and hepatic steatosis. These findings establish SA-OP (LMN) as a robust, minimally invasive transdermal gene delivery platform with prolonged storage stability for treating obesity and its metabolic comorbidities.

Long-Term Outcomes of Colon Conduits in Surgery for Primary Esophageal Cancer: A Propensity Score-Matched Comparison to Gastric Conduits.

Background: In the treatment of esophageal cancer, a gastric conduit is typically the first choice. However, when the stomach is not a viable option, the usual alternative is a colon conduit. This study compared the long-term surgical outcomes of gastric and colon conduits over the same interval and aimed to identify factors influencing the prognosis. Methods: A retrospective review was conducted of patients who underwent esophagectomy followed by reconstruction for primary esophageal cancer between January 2006 and December 2020. Results: The study included 1,545 patients, with a gastric conduit used for 1,429 (92.5%) and a colon conduit for 116 (7.5%). Using propensity-matched analysis, 116 patients were selected from each group for comparison. No significant difference was observed in long-term survival between the gastric and colon conduit groups, irrespective of anastomosis level and pathological stage. A higher proportion of patients in the colon conduit group experienced postoperative complications compared to the gastric conduit group (57.8% vs. 25%, p<0.001). Multivariable analysis revealed that age over 65 years, body mass index below 22.0 kg/m2, neoadjuvant therapy, postoperative anastomotic leakage, and renal failure were risk factors for overall survival in patients with a colon conduit. Regarding conduit-related complications, cervical anastomosis was the only significant risk factor among those with a colon conduit. Conclusion: Despite the association of colon conduits with high morbidity rates relative to gastric conduits, the long-term outcomes of colon conduits were acceptable. More consideration should be given perioperatively to the use of a colon conduit, particularly in cases involving cervical anastomosis.

Proposal of New ypStage Grouping System for Esophageal Squamous Cell Carcinoma Patients who Underwent Neoadjuvant Chemoradiotherapy followed by Surgery.

OBJECTIVE: To propose a new ypTNM grouping system to address these limitations and improve prognostic relevance. SUMMARY BACKGROUND DATA: The current 8th edition of the American Joint Committee on Cancer (AJCC) ypStage system shows unsatisfactory prognostic relevance in patients with esophageal squamous cell carcinoma (ESCC) treated with neoadjuvant chemoradiotherapy (nCRT) followed by esophagectomy. METHODS: The study cohort included 501 ESCC patients who received nCRT followed by esophagectomy at the Samsung Medical Center in Korea between 1994 and 2018 (development cohort) and 422 patients treated at Asan Medical Center (validation cohort). Recursive partitioning with a tree-structured regression model was used to develop and validate a new ypStage grouping system. RESULTS: In the new ypStage grouping system, ypStage I includes ypT0N0 only; ypStage II includes ypTis-T2N0 or ypT0-T2N1; ypStage III includes ypT3N0-N1; and ypStage IV includes ypT4N0-N1 or ypTanyN2-3. This system adequately addressed the limitations of the existing AJCC classification system, including overlapping and reversal of survival rates. Moreover, the discrimination ability of the new system was higher than that of the existing system [concordance-index (C-index): 61.9%] in the development (C-index: 66.6%) and validation (C-index: 66.0%) cohorts. NRIe was 0.17 [95% confidence interval (CI): 0.09-0.26, P-<0.001) and 0.18 (95% CI: 0.10-0.27, P-<0.001)] in the development and validation cohorts, respectively. CONCLUSIONS: The current study proposes a clear revised version of the 8th edition of the AJCC ypStage grouping system that exhibits superior prognostic stratification in patients with ESCC treated with nCRT followed by esophagectomy.

Diisobutyl phthalate (DiBP)-induced male germ cell toxicity and its alleviation approach.

Diisobutyl phthalate (DiBP) is a commonly used plasticizer in manufacturing consumer and industrial products to improve flexibility and durability. Despite of the numerous studies, however, the direct mechanism underlying the male reproductive damage of DiBP is poorly understood. In this study, we investigated the male germ cell toxicity of DiBP using GC-1 spermatogonia (spg) cells. Our results indicated that DiBP exposure causes oxidative stress and apoptosis in GC-1 spg cells. In addition, DiBP-derived autophagy activation and down-regulation of phosphoinositide 3-kinase (PI3K)-AKT and extracellular signal-regulated kinase (ERK) pathways further inhibited GC-1 spg cell proliferation, indicating that DiBP can instigate male germ cell toxicity by targeting several pathways. Importantly, a combined treatment of parthenolide, N-acetylcysteine, and 3-methyladenine significantly reduced DiBP-induced male germ cell toxicity and restored proliferation. Taken together, the results of this study can provide valuable information to the existing literature by enhancing the understanding of single phthalate DiBP-derived male germ cell toxicity and the therapeutic interventions that can mitigate DiBP damage.

What is the benefit of preserving the superior segment in anatomical thoracoscopic resections of the lower lobe?

Background: The beneficial effect of preserved superior segment (S6) after common basal segmentectomy remains unknown. We aimed to evaluate the effect of preserved superior segment on lung volume and function. Methods: Among 671 segmentectomies and 2,249 lobectomies for clinical stage IA lung cancer between 2004 and 2020, 48 patients who received thoracoscopic common basal segmentectomy were included and compared with 96 patients who received thoracoscopic lower lobectomy after propensity score matching. The variables analyzed were age, sex, comorbidity, smoking history, preoperative forced expiratory volume in one second (FEV1), clinical T stage, histology, and tumor location. Lung volume was assessed using a three-dimensional (3D) computed tomography (CT)-based volumetric method. Results: There were no significant differences between common basal segmentectomy (segmentectomy group) and lower lobectomy (lobectomy group) (4,183.8±1,114.9 versus 3,850.7±1,132.1 mL; P=0.10) in terms of preoperative CT-measured total lung volume. At the immediate postoperative median follow-up period (6.4 months), the reduced percentage of CT-measured total lung volume in the segmentectomy group was significantly larger than that in the lobectomy group (-16.2% versus -6.5%; P=0.004). The percentage of CT-measured contralateral lung volume expansion in the segmentectomy group was significantly smaller than that in the lobectomy group (-0.7% versus +8.9%; P=0.006). At the last median follow-up period (43.1 months), the reduced percentage of CT-measured total lung volume in the segmentectomy group remained larger than that in the lobectomy group (-13.0% versus -3.0%; P=0.01). The reduced percentage of postoperative FEV1 in the segmentectomy group did not differ from that in the lobectomy group (-9.9% versus -11.5%, P=0.63). Conclusions: Preserving the superior segment might not provide beneficial effect on the preservation of postoperative lung volume and function after common basal segmentectomy compared with lower lobectomy.

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.

Engineering TGF-ß inhibitor-encapsulated macrophage-inspired multi-functional nanoparticles for combination cancer immunotherapy.

BACKGROUND: The emergence of cancer immunotherapies, notably immune checkpoint inhibitors, has revolutionized anti-cancer treatments. These treatments, however, have been reported to be effective in a limited range of cancers and cause immune-related adverse effects. Thus, for a broader applicability and enhanced responsiveness to solid tumor immunotherapy, immunomodulation of the tumor microenvironment is crucial. Transforming growth factor-ß (TGF-ß) has been implicated in reducing immunotherapy responsiveness by promoting M2-type differentiation of macrophages and facilitating cancer cell metastasis. METHODS: In this study, we developed macrophage membrane-coated nanoparticles loaded with a TGF-ßR1 kinase inhibitor, SD-208 (M[Formula: see text]-SDNP). Inhibitions of M2 macrophage polarization and epithelial-to-mesenchymal transition (EMT) of cancer cells were comprehensively evaluated through in vitro and in vivo experiments. Bio-distribution study and in vivo therapeutic effects of M[Formula: see text]-SDNP were investigated in orthotopic breast cancer model and intraveneously injected metastasis model. RESULTS: M[Formula: see text]-SDNPs effectively inhibited cancer metastasis and converted the immunosuppressive tumor microenvironment (cold tumor) into an immunostimulatory tumor microenvironment (hot tumor), through specific tumor targeting and blockade of M2-type macrophage differentiation. Administration of M[Formula: see text]-SDNPs considerably augmented the population of cytotoxic T lymphocytes (CTLs) in the tumor tissue, thereby significantly enhancing responsiveness to immune checkpoint inhibitors, which demonstrates a robust anti-cancer effect in conjunction with anti-PD-1 antibodies. CONCLUSION: Collectively, responsiveness to immune checkpoint inhibitors was considerably enhanced and a robust anti-cancer effect was demonstrated with the combination treatment of M[Formula: see text]-SDNPs and anti-PD-1 antibody. This suggests a promising direction for future therapeutic strategies, utilizing bio-inspired nanotechnology to improve the efficacy of cancer immunotherapy.

What drives researcher preferences for chemical compounds? Evidence from conjoint analysis.

We investigated the attributes and attribute levels that affect researcher preferences for chemical compounds. We conducted a conjoint analysis on survey data of Korean researchers using chemical compounds from the Korean Chemical Bank (KCB). The analysis estimated the part-worth utility for each attribute's level, calculated relative importance of attributes, and classified user segmentation with different patterns. The results show that the structure database offers the highest part-worth utility to researchers, followed by high new functionality, price, screening service, and drug action data provided only by the KCB. Notably, researchers view the offer of a structured database and high new functionality as more important than other attributes in decision-making about research and development of chemical compounds. Furthermore, the results of segmentation analysis demonstrated that researchers have distinct usage patterns of chemical compounds: researchers consider structure database and high new functionality in cluster 1; and high new functionality and price in cluster 2, to be the most appealing. We discussed some policy and strategic implications based on the findings of this study and proposed some limitations.

Short-Term Effects of Centralization of the Glenohumeral Joint and Dynamic Humeral Centering on Shoulder Pain, Disability, and Grip Strength in Patients with Secondary Subacromial Impingement Syndrome.

Subacromial impingement syndrome (SIS) is one of the most common causes of shoulder pain in adults and is caused by muscle imbalance around the shoulder joint, which is referred to as secondary SIS. Centralization of the glenohumeral joint (CGH), one of the intervention methods for this, targets strengthening the control ability of the rotator cuff. Dynamic humeral centering (DHC) targets the learning of selective contractile function of the pectoralis major and latissimus dorsi as depressors of the humeral head. This study aims to determine the short-term effects of CGH and DHC on pain, disability, and grip strength in patients with secondary SIS. Forty-eight patients with secondary SIS participated in the study and were randomly allocated into three groups (CGH group (n = 16), DHC group (n = 16), and simple exercise group (n = 16)) and received the intervention for 50 min. The Constant-Murley score was used to assess shoulder pain and disability (primary outcome), and a hand-held dynamometer was used to assess grip strength (secondary outcome). Measurements were performed before the intervention and one day after the intervention. The results showed that the Constant-Murley score improved in the CGH and DHC groups. In addition, pain and disability (range of motion scores) improved in both the CGH and DHC groups. Improvements in disability (shoulder strength) and grip strength were seen only in the CGH group. Both CGH and DHC can be used as methods for short-term pain release and disability recovery in secondary SIS. In particular, CGH appears to be more effective in the short-term improvement in shoulder strength and grip strength.

[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.

Surgical outcomes of 500 robot-assisted minimally invasive esophagectomies for esophageal carcinoma.

Background: In 2003, robot-assisted minimally invasive esophagectomy (RAMIE) was first reported to overcome the technical limitations of minimally invasive esophagectomy. RAMIE requires repeated modifications to set up the robotic system, and sufficient experience is required to gain technical proficiency. This study aimed to identify the learning periods and the outcomes of RAMIE for esophageal carcinoma. Methods: We retrospectively reviewed 500 consecutive RAMIE cases for esophageal cancer from December 2008 to February 2021. The learning curve for RAMIE was identified using cumulative sum analysis. Results: In a total of 500 RAMIE patients, the Ivor Lewis and McKeown operation were performed in 267 patients (53.4%) and 192 patients (38.4%), respectively. We classified learning periods into the learning phase (first 50 cases), the developing phase (51-150 case), and the stable phase (151-500 case). The rates of vocal cord palsy (42.0% vs. 28.4%) and anastomotic leakage (10.0% vs. 6.4%) were reduced after the learning phase. The mean total operative time (420 vs. 373 min), the mean length of stay (21.6 vs. 16.7 days), and the rate of anastomotic stricture (27.0% vs. 12.4%) were significantly reduced after reaching stable phase. In the stable phase, the proportion of the Ivor Lewis operation (26.0% vs. 67.1%), neoadjuvant chemoradiation therapy (14.0% vs. 25.7%), and bilateral cervical node dissection cases (12.0% vs. 22.0%) were significantly increased. Conclusions: Fifty procedures might be needed to achieve early proficiency, and extensive experience of more than 150 procedures is needed for quality stabilization.

Fabrication of a photo-crosslinkable fluoropolymer-passivated flexible neural probe and acute recording and stimulation performances in vivo.

Herein, we fabricated fluorine-containing, polymer-based, flexible neural probes with fluorinated ethylene propylene (FEP) films as the substrates and photo-crosslinkable fluoropolymers as the passivation material. For fabrication, metal-free Au layer formation on the FEP film, the simultaneous photo-adhesion and photo-patterning technique, and the pulsed-laser scanning probe shaping technique were combined, followed by Au electrode surface modification. The resultant probes achieved a charge injection limit equal to 5.18 mC cm-2 by implementing iridium oxide-modified nanoporous Au (IrOx/NPG) structures. We performed simultaneous in vivo micro-stimulations of the Schaffer collateral fibres and recorded the evoked field excitatory postsynaptic potentials (fEPSPs) in the stratum radiatum layer of the hippocampal Cornu Ammonis 1 region using a single probe. Inducing the fEPSP at very low charge per pulse settings (3.2-3.6 nC/pulse) indicates the efficient charge injection capability of the IrOx/NPG electrode, thereby enabling safe, prolonged, and thrifty micro-stimulations. Furthermore, the single probe-induced and recorded long-term potentiation persisted for periods longer than 60 min following theta-burst stimulation. The materials used in this study are all biocompatible and chemically robust. The fabricated neural probes can be applied in chronic clinical trials in vivo.

Asia expert consensus on segmentectomy in non-small cell lung cancer: A modified Delphi study.

Objective: Segmentectomy as a parenchymal-sparing surgical approach has been recommended over lobectomy in select patients with early-stage non-small cell lung cancer. This study aimed to address 3 aspects of segmentectomy ("patient indication"; "segmentectomy approaches"; "lymph node assessment") where there is limited clinical guidance. Methods: A modified Delphi approach comprising 3 anonymous surveys and 2 expert discussions was used to establish consensus on the aforementioned topics among 15 thoracic surgeons (2 Steering Committee; 2 Task Force; 11 Voting Experts) from Asia who have extensive segmentectomy experience. Statements were developed by the Steering Committee and Task Force based on their clinical experience, published literature (rounds 1-3), and comments received from Voting Experts through surveys (rounds 2-3). Voting Experts indicated their agreement with each statement on a 5-point Likert scale. Consensus was defined as ≥70% of Voting Experts selecting either "Agree"/"Strongly Agree" or "Disagree"/"Strongly Disagree." Results: Consensus from the 11 Voting Experts was reached on 36 statements (11 "patient indication" statements; 19 "segmentation approaches" statements; 6 "lymph node assessment" statements). In rounds 1, 2, and 3, consensus was reached on 48%, 81%, and 100% of drafted statements, respectively. Conclusions: A recent phase 3 trial reported significantly improved 5-year overall survival rates for segmentectomy compared with lobectomy, proposing thoracic surgeons to consider segmentectomy as a surgical option in suitable patients. This consensus serves as a guidance to thoracic surgeons considering segmentectomy in patients with early non-small cell lung cancer, outlining key principles that surgeons should consider in surgical decision-making.

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.

Total En Bloc Spondylectomy of C7 Vertebrae for Primary Bone Tumors: The Efficacy of Autologous Sternal Structural Grafts.

AIM: To evaluate the efficacy and safety of total en bloc spondylectomy with autologous sternal structural graft, subaxial pedicle screws, and 5.5 mm titanium rods in primary bone tumor surgery. MATERIAL AND METHODS: From January 2019 to February 2020, two patients with lower cervical spine (C7) primary bone tumor underwent total en bloc spondylectomy, interbody fusion with sternal structural autograft, and posterior instrumentation using subaxial pedicle screws. The medical records and radiographic findings of the patients were reviewed. RESULTS: C7 total en bloc spondylectomy was successfully performed; the anterior column was reconstructed with an autologous sternal structural graft with posterior instrumentation using subaxial pedicle screws and 5.5 mm titanium rods. After surgery, the VAS scores of neck and radiating arm pain in both patients were relieved considerably. Bony fusion was achieved in all patient by 6 months after surgery. There were no postoperative complications associated with the donor site. CONCLUSION: Structural bone obtained from the sternum is safe and provides a viable alternative to cervical fusion for patients with primary bone tumor. It confers the advantages of autograft fusion without the complications associated with donor site morbidities.

Multi-institutional surgical outcomes of robotic single-port surgery: a Korean experience.

Background: The da Vinci single-port system (SPS) has been applied in several fields of surgery; however, only a few studies have reported its applications in general thoracic surgery. This retrospective study aimed to investigate the multi-institutional experiences of applications of SPS in Korea. Methods: The surgical outcomes of three institutions in Korea were collected and retrospectively reviewed. Results: A total of 39 surgeries were performed using SPS without conversion to multiport surgery. The patients included 16 males, and the mean age was 54.2±12.4 years. The most common pathological diagnoses were thymoma (18 cases) and benign cystic lesions (10 cases). The approach used for SPS was subxiphoid, subcostal, and intercostal in 26, 10, and 3 cases, respectively. All patients underwent the surgeries without postoperative complications. The median operation time and peak pain score were 121.4±45.4 min and 3.1±1.1. The median duration of in situ chest tube and hospital stay was 1.3±0.6 and 2.9±1.2 days, respectively. Conclusions: The application of SPS for general thoracic surgery was safe and feasible, whereas its applications remain limited to simple cases. To enable the widespread use of SPS surgery, alleviation of cost-related problems and technical improvement of SPS for complex procedures are required.

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.