Prognosis of spread through air spaces in invasive mucinous lung adenocarcinoma after curative surgery.

INTRODUCTION: The purpose of this study is to investigate the prognostic impact of spread through air spaces (STAS) in invasive mucinous adenocarcinoma (IMA). MATERIALS AND METHODS: From 2015 to 2019, patients who underwent complete resection of IMA were extracted from the prospective database. Multivariable Cox-regression analysis and inverse probability of treatment weight (IPTW) - adjusted log-rank test for 5-year recurrence-free survival (RFS) were performed. RESULTS: STAS was observed in 39.1% (53 out of 133). The STAS (+) group shows larger tumor size (2.9 ± 2.4 cm vs 3.8 ± 2.4 cm, p = 0.031) and higher incidence of lympho-vascular invasion (6 [7.5%] vs 18 [34.0%], p < 00.001) compared to the STAS (-) group. The 5-year RFS was 66.1% in the STAS (+) group and 91.8% in the STAS (-) group (p < 00.001), and the incidence of locoregional recurrence was significantly higher in the STAS (+) group than the STAS (-) group (1 [1.2%] vs 12 [22.6%], p < 00.001). Multivariable analysis revealed that STAS was associated with poor prognosis for all-recurrence (hazard ratio 2.81, 95% confidence interval 1.01-7.81, p = 0.048). After IPTW adjustment, 5-year RFS was 66.3% in the STAS (+) group and 92.9% in the STAS (-) group (p = 0.007), and risk for locoregional recurrence was greater in the STAS (+) group than the STAS (-) group (1.1 [0.9%] vs 20.8 [16.6%], p < 00.001). CONCLUSIONS: STAS showed negative prognostic impact on all-recurrence, especially due to locoregional recurrence, after curative resection of IMA.

The Optimal Treatment Strategy for Postoperative Anastomotic Leakage After Esophagectomy: a Comparative Analysis Between Endoscopic Vacuum Therapy and Conventional Treatment.

BACKGROUND: We compared the clinical outcomes between endoscopic vacuum therapy (EVT) and conventional treatment (CT) for the management of post-esophagectomy anastomotic leakage. METHODS: A retrospective review of the medical records of patients who underwent esophagectomy with esophagogastrostomy from November 2003 to August 2021 was conducted. Thirty-four patients who developed anastomotic leakage were analyzed according to whether they underwent CT (n = 13) or EVT (n = 21). RESULTS: The median time to complete healing was significantly shorter in the EVT group than in the CT group (16 [4-142] days vs. 70 [8-604] days; p = 0.011). The rate of clinical success was higher in the EVT group (90.5%) than in the CT group (66.7%, p = 0.159). A subgroup analysis showed more favorable outcomes for EVT in patients with thoracic leakage, including a higher clinical success rate (p = 0.037), more rapid complete healing (p = 0.004), and shorter hospital stays (p = 0.006). However, the results were not significantly different in patients with cervical leakage. Anastomotic strictures occurred in 3 EVT patients (14.3%) and 5 CT patients (50.0%) (p = 0.044), and the EVT group showed a trend towards improved freedom from anastomotic strictures (p = 0.105). CONCLUSIONS: EVT could be considered as an adequate treatment option for post-esophagectomy anastomotic leakage. EVT might have better clinical outcomes compared to CT for managing anastomotic leakage after transthoracic esophagogastrostomy, and further studies are needed to evaluate the effectiveness of EVT in patients who undergo cervical esophagogastrostomy.

Surgical outcomes of thoracoscopic thymectomy via the single-port subxiphoid approach versus the unilateral intercostal approach.

OBJECTIVES: The purpose of this study was to explore the safety and feasibility of video-assisted thoracic surgery (VATS) total thymectomy via the single-port subxiphoid approach compared with the intercostal approach. METHODS: From January 2018 to May 2022, patients who underwent VATS total thymectomy via the subxiphoid or unilateral intercostal approach and diagnosed with Masaoka-Koga stage I-II, non-myasthenic thymoma were included in this study. Perioperative outcomes, immediate and long-term pain evaluations were compared in a propensity score-matching analysis. RESULTS: In total, 95 patients were included and underwent the subxiphoid approach (n = 37) and the intercostal approach (n = 58). Propensity score yielded 2 well-matched cohorts of 30 patients and there was no significant demographical imbalance between the 2 groups. Compared with the intercostal approach, the subxiphoid group demonstrated favourable perioperative outcomes including the intraoperative blood loss (P = 0.025) and the median duration of hospital stay (P = 0.083). The immediate and long-term pain evaluations revealed that the subxiphoid group reported lower visual analogue scales at postoperative 24 h and lower total doses of fentanyl bolus infusions during hospitalization (P = 0.004 and 0.018, respectively), along with lower long-term neuropathic pain scale scores (P = 0.005) than patients in the intercostal group. CONCLUSIONS: VATS thymectomy via the single-port subxiphoid approach showed favourable perioperative outcomes compared to the intercostal approach. Moreover, the subxiphoid approach seemed both to cause minimal immediate postoperative pain and to have advantages in reducing long-term neuropathic pain compared with the intercostal approach.

Role of prognostic nutritional index in postoperative radiotherapy for non-small cell lung cancer.

BACKGROUND: The prognostic nutritional index (PNI) is known to be correlated with clinical outcomes in non-small cell lung cancer (NSCLC) patients. However, its role has not been studied in patients who have undergone postoperative radiotherapy (PORT). This study aimed to investigate the relationship between PNI and survival and recurrence in NSCLC patients with PORT. METHODS: We reviewed 97 stage I-III NSCLC patients who received PORT between January 2006 and December 2016 at our institution. We obtained PNI values for both pre-RT (within 1 month before PORT) and post-RT (within 2 months after PORT) by using serum albumin and lymphocyte count. A cutoff value for PNI was determined by the receiver operating characteristic curve (ROC). The median follow-up period was 52.8 months. RESULTS: The ROC curve of post-RT PNI exhibited a higher area under the curve (AUC 0.68, cut-off: 47.1) than that of pre-RT PNI (AUC 0.55, cutoff: 50.3), so the group was divided into high post-RT PNI (> 47.1) and low post-RT PNI ( ≤ 47.1). The five-year overall survival rate (OS) was 66.2% in the high post-RT group, compared with 41.8% in the low post-RT PNI group (p = 0.018). Those with both low pre-RT and low post-RT PNI had the worst five-year OS of 31.1%. Post-RT PNI (HR 0.92, p = 0.003) was an independent risk factor for mortality. CONCLUSIONS: PNI after PORT was significantly associated with survival. This finding suggests that PNI can be used as a prognostic marker.

Development of an Extended Reality Simulator for Basic Life Support Training.

OBJECTIVE: Extended Reality (XR) is a simultaneous combination of the virtual and real world. This paper presents the details of the framework and development methods for an XR basic life support (XR-BLS) simulator, as well as the results of an expert usability survey. METHODS: The XR-BLS simulator was created by employing a half-torso manikin in a virtual reality environment and using BLS education data that is in line with the 2020 American Heart Association guidelines. A head-mounted display (HMD) and hand-tracking device were used to perform chest compressions and ventilation and to enable the use of an automated external defibrillator in a virtual environment. A usability study of the XR-BLS simulator through an expert survey was also conducted. The survey consisted of a total of 8 items: 3, 2, and 2 questions about the ease of use of XR-BLS, delivery of training, and artificial intelligence (AI) instructor in the simulator, respectively. RESULTS: The XR simulator was developed, and the expert survey showed that it was easy to use, the BLS training was well delivered, and the interaction with the AI instructor was clear and understandable. DISCUSSION/CONCLUSION: The XR-BLS simulator is useful as it can conduct BLS education without requiring instructors and trainees to gather.

Poor Prognosis of Grade 2 Spread Through Air Spaces in Neuroendocrine Tumors.

BACKGROUND: Spread through air spaces (STAS) has recently emerged as a prognostic factor in lung adenocarcinoma, but little is known about the association of STAS and its grade with recurrence in neuroendocrine tumors (NETs). This study investigated the prognostic effect of STAS grade in NETs after curative resection. METHODS: Seventy-seven patients were retrospectively reviewed, including 9 with typical carcinoid (TC), 6 with atypical carcinoid (AC), 26 with large cell neuroendocrine carcinoma (LCNEC), and 36 with small cell carcinoma (SCC). STAS was defined as the presence of floating tumor cells within air spaces in the lung parenchyma beyond the edge of the main tumor. STAS was classified as grade 1 or 2 depending on whether it was found within or beyond one ×10 objective lens field away from the main tumor margin, respectively. RESULTS: Fifty-four patients (70%) had STAS, including 22% with TC, 50% with AC, 69% with LCNEC, and 86% with SCC. Patients with STAS had more nodal metastasis, lymphatic and vascular invasion, tumor necrosis, and tumor subtypes other than TC. Among STAS cases, grade 2 STAS was present in 33% of AC, 78% of LCNEC, and 87% of SCC. The 5-year recurrence-free survival (RFS) rate was 81%, 63%, and 35% in patients with no STAS, grade 1, and grade 2 STAS, respectively. Multivariate analysis found that grade 2 STAS was an independent negative prognostic factor for RFS. CONCLUSION: Although STAS itself was not associated with a poor prognosis, grade 2 STAS was an independent negative prognostic factor for RFS.

The differential prognostic impact of spread through air spaces in early-stage lung adenocarcinoma after lobectomy according to the pT descriptor.

OBJECTIVES: We evaluated the differential prognostic impact of spread through air spaces (STAS) in early-stage lung adenocarcinoma after lobectomy according to the pT descriptor. METHODS: The study population included 506 patients who underwent lobectomy with mediastinal lymph node dissection for pT1b, pT1c, and pT2a adenocarcinoma between 2011 and 2016. We divided the study population into 2 groups according to STAS status, ie, STAS (+) versus STAS (-), and stratified them according to the pT descriptor. A Cox proportional hazard model and inverse probability of treatment weight-adjusted Kaplan-Meier curves were used to evaluate the prognostic impact of STAS on recurrence-free survival (RFS) and its independency in each stratum. RESULTS: Multivariable Cox proportional hazard regression analysis demonstrated that in pT1b and pT1c strata, STAS (+) patients had a 7.02-fold and 2.89-fold greater risk of recurrence than STAS (-) patients, respectively. However, in the pT2a stratum, STAS did not affect RFS. And the RFS of the STAS (+) pT1b/c strata was similar to that of the pT2a stratum. In the pT1b/c strata, inverse probability of treatment weighting-adjusted Kaplan-Meier curves also showed that RFS was significantly worse when STAS was present. Furthermore, the risks for locoregional and distant recurrence were both greater when STAS was present. CONCLUSIONS: The presence of STAS increased the risk of recurrence independently from other poor prognostic factors in patients with pT1b/cN0M0 adenocarcinoma who underwent lobectomy, but not in pT2a patients. The presence of STAS in pT1b/cN0M0 adenocarcinoma was associated with a similar risk of recurrence to that of pT2aN0M0 adenocarcinoma.

Epigenetic readers and lung cancer: the rs2427964C>T variant of the bromodomain and extraterminal domain gene BRD3 is associated with poorer survival outcome in NSCLC.

Bromodomain and extraterminal domain (BET) proteins are epigenetic readers that regulate gene expression. We investigated whether variants in BET genes are associated with survival outcomes for lung cancer. To do this, the associations between 77 variants in BET family genes and survival outcomes were analyzed in 773 non-small-cell lung cancer (NSCLC) patients who underwent surgery (349 and 424 patients in the discovery and validation cohorts, respectively). We found that six variants were significantly associated with overall survival (OS) in the discovery cohort, and one variant (rs2506711C>T) was replicated in the validation cohort. BRD3 rs2506711C>T is located in the repressed area and has a strong linkage disequilibrium with rs2427964C>T in the promoter region. BRD3 rs2427964C>T was significantly associated with worse OS in the discovery cohort, validation cohort, and combined analysis. In a luciferase assay, promoter activity in the BRD3 rs2427964 T allele was significantly higher than that in the BRD3 rs2427964 C allele, which selectively bound with the transcriptional repressor SIN3A. Knockdown of BRD3 with BRD3-specific siRNA decreased the proliferation and migration of lung cancer cells while also increasing the rate of apoptosis. These results suggest that BRD3 rs2427964C>T increases BRD3 expression through increased promoter activity, which is associated with poor prognosis for lung cancer.

Randomized Trial of Poloxamer 407-Based Ropivacaine Hydrogel After Thoracoscopic Pulmonary Resection.

BACKGROUND: We conducted a comparative study to evaluate the efficacy of poloxamer 407-based ropivacaine hydrogel at the wound site (Gel) and continuous thoracic paravertebral block using On-Q PainBuster (On-Q; B. Braun Medical) for postoperative pain after thoracoscopic pulmonary resection. METHODS: This prospective, randomized, noninferiority study included 89 patients randomized to the Gel group (poloxamer 407-based 0.75% ropivacaine, 22.5 mg) or the On-Q group (0.2% ropivacaine, 4 mg/h for 48 hours). The primary outcome measure was total fentanyl consumption, and secondary outcome measures were the need for rescue analgesia and pain intensity using the numeric rating scale (NRS). RESULTS: There was no significant difference in total fentanyl consumption between the Gel group and the On-Q group (1504.29 ± 315.72 µg vs 1560.32 ± 274.81 µg, P = .374). Pain intensity using the NRS between the Gel group and the On-Q group demonstrated no statistical differences at 6 hours (3.56 vs 3.55, P = .958), 24 hours (3.21 vs 3.00, P = .25), 48 hours (2.75 vs 2.49, P = .233), and 72 hours (2.39 vs 2.33, P = .811), and there was no significant difference in the frequency of analgesic rescue medication use (3.70 vs 3.33, P = .417). CONCLUSIONS: We confirm the noninferiority of Gel compared with On-Q for acute postoperative pain after thoracoscopic pulmonary resection. Considering a technical simplicity and low systemic toxicity of the local injection of Gel, this analgesic modality may be worthy of further research and is thus considered to have potential as a viable alternative to On-Q for regional analgesia.

Comparison of extended reality and conventional methods of basic life support training: protocol for a multinational, pragmatic, noninferiority, randomised clinical trial (XR BLS trial).

BACKGROUND: Conventional cardiopulmonary resuscitation (CPR) training for the general public involves the use of a manikin and a training video, which has limitations related to a lack of realism and immersion. To overcome these limitations, virtual reality and extended reality technologies are being used in the field of medical education. The aim of this study is to explore the efficacy and safety of extended reality (XR)-based basic life support (BLS) training. METHODS: This study is a prospective, multinational, multicentre, randomised controlled study. Four institutions in 4 countries will participate in the study. A total of 154 participants will be randomly assigned to either the XR group or the conventional group stratified by institution and sex (1:1 ratio). Each participant who is allocated to either group will be sent to a separate room to receive training with an XR BLS module or conventional CPR training video. All participants will perform a test on a CPR manikin after the training. The primary outcome will be mean compression depth. The secondary outcome will be overall BLS performance, including compression rate, correct hand position, compression, and full release and hands-off time. DISCUSSION: Using virtual reality (VR) to establish a virtual educational environment can give trainees a sense of realism. In the XR environment, which combines the virtual world with the real world, trainees can more effectively learn various skills. This trial will provide evidence of the usefulness of XR in CPR education. TRIAL REGISTRATION: ClinicalTrials.gov NCT04736888. Registered on 29 January 2021.

Genetic variants in histone modification regions are associated with the prognosis of lung adenocarcinoma.

We investigated the association between genetic variants in the histone modification regions and the prognosis of lung adenocarcinoma after curative surgery. Potentially functional SNPs were selected using integrated analysis of ChIP-seq and RNA-seq. The SNPs were analyzed in a discovery set (n = 166) and a validation set (n = 238). The associations of the SNPs with overall survival (OS) and disease-free survival (DFS) were analyzed. A total of 279 SNPs were selected for genotyping. Among these, CAPN1 rs17583C>T was significantly associated with better OS and DFS (P = 0.001 and P = 0.007, respectively), and LINC00959 rs4751162A>G was significantly associated with worse DFS (P = 0.008). Luciferase assays showed a significantly lower promoter activity of CAPN1 in the rs17583 T allele than C allele (P = 0.008), and consistently the CT + TT genotypes had significantly lower CAPN1 expression than CC genotype (P = 0.01) in clinical samples. The rs4751162 G allele had higher promoter activity of GLRX3 than A allele (P = 0.05). The motif analyses and ChIP-qPCR confirmed that the variants are located in the active promoter/enhancer regions where transcription factor binding occurs. This study showed that genetic variants in the histone modification regions could predict the prognosis of lung adenocarcinoma after surgery.

Video-assisted thoracic surgery sleeve resection and bronchoplasty using 3D imaging system: its safety and efficacy.

BACKGROUND: Video-assisted thoracic surgery sleeve resection with bronchial anastomosis or bronchoplasty is a technically demanding procedure. Three-dimensional endoscopic surgery has been reported to be helpful in decreasing operation time and improving spatial perception with less surgical errors, but there have been rare reports about relatively difficult thoracoscopic procedures utilizing 3D thoracoscope. We performed this study to evaluate early clinical outcomes of thoracoscopic sleeve resection and bronchoplasty utilizing 3D thoracoscope. METHODS: Data from a total of 36 patients who underwent thoracoscopic sleeve lobectomy or bronchoplasty at our institution from December 2015 to October 2017 were retrospectively reviewed. Three-port approach with one utility incision was used with a 10 mm, 30° three-dimensional thoracoscope. Twenty-three patients (81%) were male, and mean age was 65.9 ± 9.4 years. Fourteen patients (38.9%) underwent sleeve resection with bronchial anastomosis, 22 (61.1%) underwent wedge or simple bronchoplasty, and one patient received concomitant PA procedure. Bronchial anastomosis sites were not covered with viable tissue flaps. RESULTS: There was no (0%) suture needle injury from spatial misperception during bronchoplasty or sleeve anastomosis. There was no (0%) operative mortality. The pathologic report revealed squamous cell carcinoma (63.9%), adenocarcinoma (19.4%), carcinoid (6.9%), adenosquamous carcinoma (3.4%), and sarcomatoid carcinoma (2.8%). One (2.8%) late mortality was due to systemic recurrence of sarcomatoid carcinoma. There was no (0.0%) anastomotic failure. The mean number of dissected lymph nodes were 27.4 ± 13.2, and mean operation time was 216.8 ± 60.0 min. Median postoperative 24-h drain amount was 315 mL. Median chest tube days and hospital days were 4 and 6, respectively. Two patients (5.6%) had complications greater than Clavien-Dindo grade II-one case of ARDS, and the other case of a delayed bronchopleural fistula. CONCLUSIONS: Thoracoscopic sleeve resection and bronchoplasty utilizing HD 3D thoracoscope is a safe and effective procedure with excellent early clinical outcomes. Further investigation for long-term outcomes will be needed.

Prognostic Significance of the Extranodal Extension of Regional Lymph Nodes in Stage III-N2 Non-Small-Cell Lung Cancer after Curative Resection.

The present study investigated the prognostic role of extranodal extension (ENE) in stage III-N2 non-small-cell lung cancer (NSCLC) following curative surgery. From January 2005 to December 2018, pathologic stage III-N2 disease was diagnosed in 371 patients, all of whom underwent anatomic pulmonary resection accompanied by mediastinal lymph node dissection. This study included 282 patients, after excluding 89 patients who received preoperative chemotherapy or incomplete surgical resection. Their lymph nodes were processed; after hematoxylin and eosin staining, histopathologic slides of the metastatic nodes were reviewed by a designated pathologist. Predictors of disease free survival (DFS), including age, sex, operation type, pathologic T stage, nodal status, visceral pleural invasion, perioperative treatment, and the presence of ENE, were investigated. Among the 282 patients, ENE was detected in 85 patients (30.1%). ENE presence was associated with advanced T stage (p = 0.034), N2 subgroups (p < 0.001), lymphatic invasion (p = 0.001), and pneumonectomy (p = 0.002). The multivariable analysis demonstrated that old age (p < 0.001), advanced T stage (p = 0.012), N2 subgroups (p = 0.005), and ENE presence (p = 0.005) were significant independent predictors of DFS. The DFS rate at five years was 21.4% in patients who had ENE and 43.4% in patients who did not have ENE (p < 0.001). The presence of ENE, coupled with tumor-node-metastasis staging, should be recognized as a meaningful prognostic factor in stage III-N2 NSCLC patients.

Synchrotron Radiation-Based Refraction-Contrast Tomographic Images Using X-ray Dark-Field Imaging Optics in Human Lung Adenocarcinoma and Histologic Correlations.

The aim of this study was to evaluate the clinical implication of synchrotron radiation imaging techniques for human lung adenocarcinoma in comparison with pathologic examination. A refraction-based tomographic imaging technique called the X-ray dark-field imaging (XDFI) method was used to obtain computed tomographic images of human lung adenocarcinoma at the beam line at Photon Factory BL 14B at the High Energy Accelerator Research Organization (KEK) in Tsukuba, Japan. Images of normal lung tissue were also obtained using the same methods and reconstructed as 3D images. Both reconstructed images were compared with pathologic examinations from histologic slides which were made with identical samples. Pulmonary alveolar structure including terminal bronchioles, alveolar sacs, and vasculatures could be identified in synchrotron radiation images of normal lung. Hyperplasia of interstitial tissue and dysplasia of alveolar structures were noticed in images of lung adenocarcinoma. Both synchrotron radiation images were considerably correlated with images from histologic slides. Lepidic patterns of cancer tissue were distinguished from the invasive area in synchrotron radiation images of lung adenocarcinoma. Refraction-contrast tomographic techniques using synchrotron radiation could provide high-resolution images of lung adenocarcinoma which are compatible with those from pathologic examinations.

Genetic Polymorphisms in Activating Transcription Factor 3 Binding Site and the Prognosis of Early-Stage Non-Small Cell Lung Cancer.

BACKGROUND: Activating transcription factor 3 (ATF3) plays a significant role in cancer development and progression. We investigated the association between variants in expression quantitative trait loci (eQTLs) within ATF3 binding regions and the prognosis of non-small cell lung cancer (NSCLC) after surgery. METHODS: A total of 772 patients with NSCLC who underwent curative surgery were enrolled. Using a public database (http://galaxyproject.org), we selected 104 single nucleotide polymorphisms (SNPs) in eQTLs in the ATF3 binding regions. The association of those SNPs with disease-free survival (DFS) was evaluated. RESULTS: Among those SNPs, HAX1 rs11265425T>G was associated with significantly worse DFS (aHR = 1.30, 95% CI = 1.00-1.69, p = 0.05), and ME3 rs10400291C>A was associated with significantly better DFS (aHR = 0.66, 95% CI = 0.46-0.95, p = 0.03). Regarding HAX1 rs11265425T>G, the significant association remained only in adenocarcinoma, and the association was significant only in squamous cell carcinoma regarding ME3 rs10400291C>A. ChIP-qPCR assays showed that the two variants reside in active enhancers where H3K27Ac and ATF3 binding occurs. Promoter assays showed that rs11265425 G allele had significantly higher HAX1 promoter activity than T allele. HAX1 RNA expression was significantly higher in tumor than in normal lung, and higher in rs11265425 TG+GG genotypes than in TT genotype. Conversely, ME3 expression was significantly lower in tumor than in normal lung, and higher in rs10400291 AA genotype than in CC+CA genotypes. CONCLUSIONS: In conclusion, this study shows that the functional polymorphisms in ATF3 binding sites, HAX1 rs11265425T>G and ME3 rs10400291C>A are associated with the clinical outcomes of patients in surgically resected NSCLC.

Prognostic significance of tumor spread through air spaces in patients with stage IA part-solid lung adenocarcinoma after sublobar resection.

OBJECTIVES: The purpose of this study was to assess the clinicopathologic implications of tumor spread through air spaces (STAS) in patients with stage IA part-solid lung adenocarcinoma after sublobar resection. MATERIALS AND METHODS: Medical records of patients with stage IA part-solid adenocarcinoma who underwent curative pulmonary resection between February 2009 and December 2016 were retrospectively reviewed. The clinicopathological features of STAS and its influence on postoperative recurrence and survival were investigated. RESULTS: Among the 115 patients with stage IA part-solid adenocarcinoma who underwent wedge resection, 20 (17.4 %) had STAS. The multivariable analysis showed presence of STAS [HR (hazard ratio), 9.447; p = 0.002) and a larger invasive component size (HR, 1.097; p = 0.034) were independent risk factors for recurrence. The 5-year freedom from recurrence rates were 62.4 % and 97.9 % in cases with and without STAS, respectively (p < 0.001), and the 5-year disease-free survival rates were 58.5 % and 97.9 % in cases with and without STAS, respectively (p < 0.001). The presence of STAS was associated with old age (p = 0.030), male gender (p = 0.023), acinar predominant histologic pattern (p = 0.004), presence of micropapillary pattern (p < 0.001), lymphovascular invasion (p < 0.001) and larger invasive component (p < 0.001). CONCLUSION: STAS could be an important prognostic factor in patients with stage IA part-solid lung adenocarcinoma after sublobar resection. Effective preoperative evaluation and postoperative surveillance may help improve the outcome of patients with small part-solid nodules, particularly when accompanied by STAS.

Tumor spread through air spaces (STAS): prognostic significance of grading in non-small cell lung cancer.

Tumor spread through air spaces (STAS) is an invasive pattern of lung cancer that was recently described. In this study, we investigated the association between the extent of STAS and clinicopathological characteristics and patient outcomes in resected non-small cell lung cancers (NSCLCs). STAS has been prospectively described from 2008 and graded its extent with a two-tiered system (STAS I: <2500 µm [one field of ×10 objective lens] from the edge of tumor and STAS II: ≥2500 µm from the edge of tumor) from 2011 in Seoul National University Bundang Hospital. We retrospectively analyzed the correlations between the extent of STAS and clinicopathologic characteristics and prognostic significance in 1869 resected NSCLCs. STAS was observed in 765 cases (40.9%) with 456 STAS I (24.4%) and 309 STAS II (16.5%). STAS was more frequently found in patients with adenocarcinoma (ADC) (than squamous cell carcinoma), pleural invasion, lymphovascular invasion, and/or higher pathologic stage. In ADC, there were significant differences in recurrence free survival (RFS), overall survival (OS), and lung cancer specific survival (LCSS) according to the extent of STAS. In stage IA non-mucinous ADC, multivariate analysis revealed that STAS II was significantly associated with shorter RFS and LCSS (p < 0.001 and p = 0.006, respectively). In addition, STAS II was an independent poor prognostic factor for recurrence in both limited and radical resection groups (p = 0.001 and p = 0.023, respectively). In conclusion, presence of STAS II was an independent poor prognostic factor in stage IA non-mucinous ADC regardless of the extent of resection.

Predictive Factors for Lymph Node Metastasis in Clinical Stage I Part-Solid Lung Adenocarcinoma.

BACKGROUND: Accurate clinical staging of tumors with a small solid portion is essential for developing an appropriate treatment plan. This study evaluated predictive factors for lymph node (LN) metastasis in patients with clinical stage I part-solid lung adenocarcinoma. METHODS: Medical records of patients with clinical stage I part-solid adenocarcinoma who underwent anatomic pulmonary resection with systematic node evaluation between January 2009 and June 2018 were retrospectively reviewed. To identify predictive factors for LN metastasis, univariate and multivariable logistic regression analyses were performed. RESULTS: Among the 593 patients in this study, the overall prevalence of LN metastasis was 3.7% (n = 22), which included 3.0% (n = 18) of patients with N1 LN metastasis and 1.5% (n = 9) of patients with N2 LN metastasis. Combined N1 and N2 nodal involvement was observed in 5 patients. Nodal metastasis was not observed in tumors with a solid portion sized 1.1 cm or smaller. The nodal metastasis rates in cT1b, cT1c, and cT2a tumors were 5.5% (13 of 237), 7.1% (6 of 84), and 13.6% (3 of 22), respectively. According to the multivariable analysis, predictive factors included the size of the solid portion (P = .015) and the high maximum standardized uptake value (SUVmax) of the primary tumor (P = .044). CONCLUSIONS: Large solid portion and high SUVmax of the primary tumor were predictive factors of LN metastasis in patients with clinical stage I part-solid lung adenocarcinoma. Systematic LN evaluation should be performed, especially in those who have a large solid portion and high SUVmax of the primary tumor.