ASO Author Reflections: The Timeless Debate Between Ivor-Lewis or McKeown Esophagectomy.

Ivor-Lewis (IL) operation, esophagectomy and intrathoracic esophagogastrostomy and McKeown (MK) operation, esophagectomy, and cervical esophagogastrostomy are the most common procedures for esophageal cancer. The authors reported that the oncological outcomes and completeness of upper mediastinal dissection among esophageal squamous cell carcinoma patients undergoing the IL or MK operations were not different in previous paper. Whether the IL procedure can show equivalent oncologic outcomes as compared to the MK procedure in cases of upper esophageal cancer needs to be further studied in the future. In addition, a comparison of the functional outcomes and quality of life between patients who had undergone the IL and MK operations needs to be explored.

Comparison of the Oncologic Outcomes for Patients with Middle to Lower Esophageal Squamous Cell Carcinoma Undergoing Surgical Treatment Using the Ivor-Lewis or McKeown Operation.

BACKGROUND: The upper mediastinum is the most common metastatic site of esophageal squamous cell carcinoma (ESCC), and complete dissection of this region is important for oncologic reasons. This study aimed to compare the oncologic outcomes and completeness of upper mediastinal dissection for ESCC patients undergoing the Ivor-Lewis (IL) or McKeown (MK) operations. METHODS: Between 2013 and 2018, 680 patients (IL, 433; MK, 247) underwent upfront esophagectomy with two-field lymph node (LN) dissection for mid-to-lower ESCCs. Propensity score-matching (1:1 ratio) was performed to minimize the effects of confounding factors. RESULTS: The mean age was 64.5 ± 8.8 years, and 635 (93.4%) of the patients were male. The median follow-up period was 71.66 months (interquartile range [IQR], 59.60-91.04 months). The IL group had a higher mean age, lower body mass index, higher proportion of advanced T and N, and higher adjuvant therapy rates, but these differences were well-balanced after propensity score-matching. The mean number of dissected LNs at the mediastinum and at the right recurrent laryngeal nerve (RLN) were similar between the two groups after matching, whereas the IL group exhibited a slightly greater number of dissected LNs at the left RLN. Among the matched patients, the IL and MK groups exhibited similar 5-year overall survival (OS: 75.1% vs 78.0%; p = 0.368). The multivariate model showed no differences in OS, disease-free survival, or recurrence-free survival for locoregional, upper mediastinum, or neck between the two groups. CONCLUSIONS: This study suggests that both the IL and MK operations are oncologically feasible for patients with mid-to-lower ESCC.

Therapeutic Potential of Mangosteen Pericarp Extract-Loaded Liposomes against Superficial Skin Infection Caused by Staphylococcus pseudintermedius in a Murine Model.

α-mangostin (α-MG) demonstrates antibacterial activity against Staphylococcus species. Therefore, this study aimed to explore the antibacterial activity of α-MG-rich mangosteen pericarp extract (MPE)-loaded liposomes against Staphylococcus isolates from companion animal skin diseases in vitro and evaluated their therapeutic potential in a murine model of superficial skin infection caused by S. pseudintermedius. α-MG-rich extract was purified from mangosteen pericarp and then complexed with γ-cyclodextrin (γ-CD), forming the inclusion complexes. Nanoliposomes containing MPE and γ-CD complexes were prepared by adding lecithin and casein. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of MPE-loaded liposomes were determined using agar dilution and broth microdilution methods. The therapeutic potential of MPE-loaded liposomes was evaluated in vivo on tape-stripped skin lesions infected with S. pseudintermedius. Purified MPE and MPE-loaded liposomes contained 402.43 mg/g and 18.18 mg/g α-MG, respectively. MPE-loaded liposomes showed antibacterial activity against clinical Staphylococcus isolates in vitro but did not show antibacterial activity against Gram-negative bacterial isolates. MPE-loaded liposomes demonstrated consistent MICs and MBCs against Staphylococcus isolates. These liposomes significantly reduced bacterial numbers and lesional sizes in a superficial skin infection model. Moreover, they reconstructed the epidermal barrier in skin lesions. The therapeutic concentrations of MPE-loaded liposomes did not induce cytotoxicity in canine progenitor epidermal keratinocyte cells. In conclusion, MPE-loaded liposomes hold promise for the development of a prospective topical formulation to treat superficial pyoderma in companion animals.

Smoking-attributable Mortality in Korea, 2020: A Meta-analysis of 4 Databases.

OBJECTIVES: Estimating the number of deaths caused by smoking is crucial for developing and evaluating tobacco control and smoking cessation policies. This study aimed to determine smoking-attributable mortality (SAM) in Korea in 2020. METHODS: Four large-scale cohorts from Korea were analyzed. A Cox proportional-hazards model was used to determine the hazard ratios (HRs) of smoking-related death. By conducting a meta-analysis of these HRs, the pooled HRs of smoking-related death for 41 diseases were estimated. Population-attributable fractions (PAFs) were calculated based on the smoking prevalence for 1995 in conjunction with the pooled HRs. Subsequently, SAM was derived using the PAF and the number of deaths recorded for each disease in 2020. RESULTS: The pooled HR for all-cause mortality attributable to smoking was 1.73 for current men smokers (95% confidence interval [CI], 1.53 to 1.95) and 1.63 for current women smokers (95% CI, 1.37 to 1.94). Smoking accounted for 33.2% of all-cause deaths in men and 4.6% in women. Additionally, it was a factor in 71.8% of men lung cancer deaths and 11.9% of women lung cancer deaths. In 2020, smoking was responsible for 53 930 men deaths and 6283 women deaths, totaling 60 213 deaths. CONCLUSIONS: Cigarette smoking was responsible for a significant number of deaths in Korea in 2020. Monitoring the impact and societal burden of smoking is essential for effective tobacco control and harm prevention policies.

Practice pattern and risk of not receiving planned surgery after neoadjuvant chemoradiotherapy for locally advanced oesophageal squamous cell carcinoma.

OBJECTIVES: Unlike the initial plan, some patients with oesophageal squamous cell carcinoma cannot or do not receive surgery after neoadjuvant chemoradiotherapy (nCRT). This study aimed to report the epidemiology of patients not receiving surgery after nCRT and to evaluate the potential risk of refusing surgery. METHODS: We analysed patients with clinical stage T3-T4aN0M0 or T1-T4aN1-N3M0 oesophageal squamous cell carcinoma who underwent nCRT as an initial treatment intent between January 2005 and March 2020. Patients not receiving surgery were categorized using predefined criteria. To evaluate the risk of refusing surgery, a propensity-matched comparison with those who received surgery was performed. Recurrence-free (RFS) and overall survival (OS) was compared between groups, according to clinical response to nCRT. RESULTS: Among the study population (n = 715), 105 patients (14.7%) eventually failed to reach surgery. There were three major patterns of not receiving surgery: disease progression before surgery (n = 25), functional deterioration at reassessment (n = 47), and patient's refusal without contraindications (n = 33). After propensity-score matching, the RFS curves of the surgery group and the refusal group were significantly different (P < 0.001), while OS curves were not significantly different (P = 0.069). In patients who achieved clinical complete response on re-evaluation, no significant difference in the RFS curves (P = 0.382) and in the OS curves (P = 0.290) was observed between the surgery group and the refusal group. However, among patients who showed partial response or stable disease on re-evaluation, the RFS and OS curves of the refusal group were overall significantly inferior compared to those of the surgery group (both P < 0.001). The 5-year RFS rates were 10.3% for the refusal group and 48.2% for the surgery group, and the 5-year OS rates were 8.2% for the refusal group and 46.1% for the surgery group. CONCLUSIONS: Patient's refusal remains one of the major obstacles in completing the trimodality therapy for oesophageal squamous cell carcinoma. Refusing surgery when offered may jeopardize oncological outcome, particularly in those with residual disease on re-evaluation after nCRT. These results provide significant implications for consulting patients who are reluctant to oesophagectomy after nCRT.

Risk Factor Analysis of Morbidity and 90-Day Mortality of Curative Resection in Patients with Stage IIIA-N2 Non-Small Cell Lung Cancer after Induction Concurrent Chemoradiation Therapy.

Background: Major pulmonary resection after neoadjuvant concurrent chemoradiation therapy (nCCRT) is associated with a substantial risk of postoperative complications. This study investigated postoperative complications and associated risk factors to facilitate the selection of suitable surgical candidates following nCCRT in stage IIIA-N2 non-small cell lung cancer (NSCLC). Methods: We conducted a retrospective analysis of patients diagnosed with clinical stage IIIA-N2 NSCLC who underwent surgical resection following nCCRT between 1997 and 2013. Perioperative characteristics and clinical factors associated with morbidity and mortality were analyzed using univariable and multivariable logistic regression. Results: A total of 574 patients underwent major lung resection after induction CCRT. Thirty-day and 90-day postoperative mortality occurred in 8 patients (1.4%) and 41 patients (7.1%), respectively. Acute respiratory distress syndrome (n=6, 4.5%) was the primary cause of in-hospital mortality. Morbidity occurred in 199 patients (34.7%). Multivariable analysis identified significant predictors of morbidity, including patient age exceeding 70 years (odds ratio [OR], 1.8; p=0.04), low body mass index (OR, 2.6; p=0.02), and pneumonectomy (OR, 1.8; p=0.03). Patient age over 70 years (OR, 1.8; p=0.02) and pneumonectomy (OR, 3.26; p<0.01) were independent predictors of mortality in the multivariable analysis. Conclusion: In conclusion, the surgical outcomes following nCCRT are less favorable for individuals aged over 70 years or those undergoing pneumonectomy. Special attention is warranted for these patients due to their heightened risks of respiratory complications. In high-risk patients, such as elderly patients with decreased lung function, alternative treatment options like definitive CCRT should be considered instead of surgical resection.

Clonal Distribution and Its Association With the Carbapenem Resistance Mechanisms of Carbapenem-Non-Susceptible Pseudomonas aeruginosa Isolates From Korean Hospitals.

Background: Carbapenem resistance in Pseudomonas aeruginosa is a serious global health problem. We investigated the clonal distribution and its association with the carbapenem resistance mechanisms of carbapenem-non-susceptible P. aeruginosa isolates from three Korean hospitals. Methods: A total of 155 carbapenem-non-susceptible P. aeruginosa isolates collected between 2011 and 2019 were analyzed for sequence types (STs), antimicrobial susceptibility, and carbapenem resistance mechanisms, including carbapenemase production, the presence of resistance genes, OprD mutations, and the hyperproduction of AmpC ß-lactamase. Results: Sixty STs were identified in carbapenem-non-susceptible P. aeruginosa isolates. Two high-risk clones, ST235 (N=41) and ST111 (N=20), were predominant; however, sporadic STs were more prevalent than high-risk clones. The resistance rate to amikacin was the lowest (49.7%), whereas that to piperacillin was the highest (92.3%). Of the 155 carbapenem-non-susceptible isolates, 43 (27.7%) produced carbapenemases. Three metallo-ß-lactamase (MBL) genes, blaIMP-6 (N=38), blaVIM-2 (N=3), and blaNDM-1 (N=2), were detected. blaIMP-6 was detected in clonal complex 235 isolates. Two ST773 isolates carried blaNDM-1 and rmtB. Frameshift mutations in oprD were identified in all isolates tested, regardless of the presence of MBL genes. Hyperproduction of AmpC was detected in MBL gene-negative isolates. Conclusions: Frameshift mutations in oprD combined with MBL production or hyperproduction of AmpC are responsible for carbapenem resistance in P. aeruginosa. Further attention is required to curb the emergence and spread of new carbapenem-resistant P. aeruginosa clones.

Preoperative DLco and FEV1 are correlated with postoperative pulmonary complications in patients after esophagectomy.

Limited information is available regarding the association between preoperative lung function and postoperative pulmonary complications (PPCs) in patients with esophageal cancer who undergo esophagectomy. This is a retrospective cohort study. Patients were classified into low and high lung function groups by the cutoff of the lowest fifth quintile of forced expiratory volume in 1 s (FEV1) %predicted (%pred) and diffusing capacity of the carbon monoxide (DLco) %pred. The PPCs compromised of atelectasis requiring bronchoscopic intervention, pneumonia, and acute lung injury/acute respiratory distress syndrome. Modified multivariable-adjusted Poisson regression model using robust error variances and inverse probability treatment weighting (IPTW) were used to assess the relative risk (RR) for the PPCs. A joint effect model considered FEV1%pred and DLco %pred together for the estimation of RR for the PPCs. Of 810 patients with esophageal cancer who underwent esophagectomy, 159 (19.6%) developed PPCs. The adjusted RR for PPCs in the low FEV1 group relative to high FEV1 group was 1.48 (95% confidence interval [CI] = 1.09-2.00) and 1.98 (95% CI = 1.46-2.68) in the low DLco group relative to the high DLco group. A joint effect model showed adjusted RR of PPCs was highest in patients with low DLco and low FEV1 followed by low DLco and high FEV1, high DLco and low FEV1, and high DLco and high FEV1 (Reference). Results were consistent with the IPTW. Reduced preoperative lung function (FEV1 and DLco) is associated with post-esophagectomy PPCs. The risk was further strengthened when both values decreased together.

Surgical outcomes and survival following esophagectomy for squamous cell carcinoma with or without liver cirrhosis: retrospective cohort study.

BACKGROUND AND AIMS: Esophageal squamous cell carcinoma (ESCC) shares common risk factors with liver cirrhosis (LC). The influence of LC in patients with ESCC has not been fully investigated. This study aimed to investigate the postoperative and long-term survival outcomes of esophagectomy for ESCC according to LC presence. METHODS: Among patients who underwent curative-intent surgery for ESCC between 1994 and 2018, 121 patients with Child-Pugh class A LC and 2810 patients without LC were compared. RESULTS: Among the LC patients, 73 (60.3%) were diagnosed with LC before surgery and 48 (39.7%) were diagnosed intraoperatively. There were no significant differences in baseline characteristics between patients with LC and those without LC. However, intraoperative blood loss was higher, and operation time, hospital stay, and ICU stay were longer in patients with LC than in those without LC. Moreover, the reoperation, 30-day morbidity (60.6 vs. 73.6%, P =0.006) and 90-day mortality (2.2 vs. 4.9%, P =0.049) were significantly higher in patients with LC. The 5-year overall survival (OS) rate was significantly higher in patients without LC than in those with LC. After adjusting the confounding variables, LC was an adverse risk factor of OS (hazard ratio 1.402, P =0.004). Among patients with LC, the Model of End-Stage Liver Disease score was related to the development of complications of grade more than III (odds ratio 1.459, P =0.013). CONCLUSION: ESCC patients with Child-Pugh class A LC have high incidences of postoperative morbidity and mortality, and poor OS. Thus, careful patient selection, meticulous operation, and careful postoperative care are needed.

Contralateral Pulmonary Resection after Pneumonectomy.

Background: Contralateral pulmonary resection after pneumonectomy presents considerable challenges, and few reports in the literature have described this procedure. Methods: We retrospectively reviewed the medical records of all patients who underwent contralateral lung resection following pneumonectomy for any reason at our institution between November 1994 and December 2020. Results: Thirteen patients (9 men and 4 women) were included in this study. The median age was 57 years (range, 35-77 years), and the median preoperative forced expiratory volume in 1 second was 1.64 L (range, 1.17-2.12 L). Contralateral pulmonary resection was performed at a median interval of 44 months after pneumonectomy (range, 6-564 months). Surgical procedures varied among the patients: 10 underwent single wedge resection, 2 were treated with double wedge resection, and 1 underwent lobectomy. Diagnoses at the time of contralateral lung resection included lung cancer in 7 patients, lung metastasis from other cancers in 3 patients, and tuberculosis in 3 patients. Complications were observed in 4 patients (36%), including acute kidney injury, pneumothorax following chest tube removal, pneumonia, and prolonged air leak. No cases of operative mortality were noted. Conclusion: In carefully selected patients, contralateral pulmonary resection after pneumonectomy can be accomplished with acceptable operative morbidity and mortality.

Factors affecting accuracy of clinical staging in resectable non-small cell lung cancer in a real-world study.

BACKGROUND: The clinical staging of non-small cell lung cancer (NSCLC) is well known to be related to their prognosis. However, there is usually a discrepancy between clinical staging and pathological staging. There are few analyses of clinical staging accuracy in patients with NSCLC. We compared the concordance rate between clinical and pathological staging of NSCLC and evaluated factors affecting the accuracy in real-world data. METHODS: Altogether, 811 patients with primary NSCLC who had undergone curative lung resection surgery in Severance Hospital from January 2019 to December 2020 were retrospectively reviewed. We used the eighth edition of the American Joint Committee on Cancer TNM staging. RESULTS: Among 811 patients, endobronchial ultrasound (EBUS) and positron emission tomography (PET-CT) were performed in 31.6% and 96.7%, respectively. The concordance rates between clinical and pathological TNM staging, T factor, and N factor, were 68.7%, 77.7%, and 85.8%, respectively. With multivariable logistic regression analysis, current smokers (OR 0.49; 95% CI: 0.32-0.76, p = 0.001) and a higher clinical stage (p < 0.001) contributed to the clinical staging inaccuracy. Additionally, the presence of a bronchoscopy specialist was significantly associated with clinical staging accuracy (OR 1.53; 95% CI: 1.10-2.13, p = 0.011). CONCLUSION: Clinical staging accuracy in NSCLC improved compared to before the widespread use of PET-CT and EBUS in clinical staging work-up. Smoking history and absence of expert bronchoscopy specialists showed a meaningful correlation with the inaccuracy of clinical staging. Thus, training more bronchoscopy experts would improve the staging accuracy of NSCLC, which could positively affect the prognosis of NSCLC.

PD-L1 expression in resected lung adenocarcinoma: prevalence and prognostic significance in relation to the IASLC grading system.

AIMS: Programmed death-ligand 1 (PD-L1) expression is a predictive biomarker for adjuvant immunotherapy and has been linked to poor differentiation in lung adenocarcinoma. However, its prevalence and prognostic role in the context of the novel histologic grade has not been evaluated. METHODS: We analysed a cohort of 1233 patients with resected lung adenocarcinoma where PD-L1 immunohistochemistry (22C3 assay) was reflexively tested. Tumour PD-L1 expression was correlated with the new standardized International Association for the Study of Lung Cancer (IASLC) histologic grading system (G1, G2, and G3). Clinicopathologic features including patient outcome were analysed. RESULTS: PD-L1 was positive (≥1%) in 7.0%, 23.5%, and 63.0% of G1, G2, and G3 tumours, respectively. PD-L1 positivity was significantly associated with male sex, smoking, and less sublobar resection among patients with G2 tumours, but this association was less pronounced in those with G3 tumours. PD-L1 was an independent risk factor for recurrence (adjusted hazard ratio [HR] = 3.25, 95% confidence intervals [CI] = 1.93-5.48, P < 0.001) and death (adjusted HR = 2.69, 95% CI = 1.13-6.40, P = 0.026) in the G2 group, but not in the G3 group (adjusted HR for recurrence = 0.94, 95% CI = 0.64-1.40, P = 0.778). CONCLUSION: PD-L1 expression differs substantially across IASLC grades and identifies aggressive tumours within the G2 subgroup. This knowledge may be used for both prognostication and designing future studies on adjuvant immunotherapy.

Surgical Outcomes of Cervical Esophageal Cancer: A Single-Center Experience.

Background: Cervical esophageal cancer is a rare malignancy that requires specialized care. While definitive chemoradiation is the standard treatment approach, surgery remains a valuable option for certain patients. This study examined the surgical outcomes of patients with cervical esophageal cancer. Methods: The study involved a retrospective review and analysis of 24 patients with cervical esophageal cancer. These patients underwent surgical resection between September 1994 and December 2018. Results: The mean age of the patients was 61.0±10.2 years, and 22 (91.7%) of them were male. Furthermore, 21 patients (87.5%) had T3 or T4 tumors, and 11 (45.8%) exhibited lymph node metastasis. Gastric pull-up with esophagectomy was performed for 19 patients (79.2%), while 5 (20.8%) underwent free jejunal graft with cervical esophagectomy. The 30-day operative mortality rate was 8.3%. During the follow-up period, complications included leakage at the anastomotic site in 9 cases (37.5%) and graft necrosis of the gastric conduit in 1 case. Progression to oral feeding was achieved in 20 patients (83.3%). Fifteen patients (62.5%) displayed tumor recurrence. The median time from surgery to recurrence was 10.5 months, and the 1-year recurrence rate was 73.3%. The 1-year and 3-year survival rates were 75% and 33.3%, respectively, with a median survival period of 17 months. Conclusion: Patients with cervical esophageal cancer who underwent surgical resection faced unfavorable outcomes and relatively poor survival. The selection of cases and decision to proceed with surgery should be made cautiously, considering the risk of severe complications.

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.

Outcomes of Completion Lobectomy for Locoregional Recurrence after Sublobar Resection in Patients with Non-small Cell Lung Cancer.

Background: This retrospective study aimed to determine the treatment patterns and the surgical and oncologic outcomes after completion lobectomy (CL) in patients with locoregionally recurrent stage I non-small cell lung cancer (NSCLC) who previously underwent sublobar resection. Methods: Data from 36 patients who initially underwent sublobar resection for clinical, pathological stage IA NSCLC and experienced locoregional recurrence between 2008 and 2016 were analyzed. Results: Thirty-six (3.6%) of 1,003 patients who underwent sublobar resection for NSCLC experienced locoregional recurrence. The patients' median age was 66.5 (range, 44-77) years at the initial operation, and 28 (77.8%) patients were men. Six (16.7%) patients underwent segmentectomy and 30 (83.3%) underwent wedge resection as the initial operation. The median follow-up from the initial operation was 56 (range, 9-150) months. Ten (27.8%) patients underwent CL, 22 (61.1%) underwent non-surgical treatments (chemotherapy, radiation, concurrent chemoradiation therapy), and 4 (11.1%) did not receive treatment or were lost to follow-up after recurrence. Patients who underwent CL experienced no significant complications or deaths. The median follow-up time after CL was 64.5 (range, 19-93) months. The 5-year overall survival (OS) and post-recurrence survival (PRS) were higher in the surgical group than in the non-surgical (p<0.001) and no-treatment groups (p<0.001). Conclusion: CL is a technically demanding but safe procedure for locoregionally recurrent stage I NSCLC after sublobar resection. Patients who underwent CL had better OS and PRS than patients who underwent non-surgical treatments or no treatments; however, a larger cohort study and long-term surveillance are necessary.

Clinical Significance of the Proposed Pathologic Criteria for Invasion by the International Association for the Study of Lung Cancer in Resected Nonmucinous Lung Adenocarcinoma.

INTRODUCTION: Accurate diagnostic criteria for tumor invasion are essential for precise pathologic tumor (pT) staging. Recently, the International Association for the Study of Lung Cancer (IASLC) Pathology Committee suggested a new set of criteria for assessing tumor invasion, but the clinical usefulness of the proposed criteria has not been evaluated. METHODS: The study included 1295 patients with resected part-solid lung adenocarcinoma from January 2017 to December 2019 at the Samsung Medical Center, Seoul, Korea. The revised pT stage was determined by the extent of the newly measured invasive component using the IASLC criteria. The primary outcome was to compare the performance of the revised pT stage with the original pT stage in predicting recurrence-free survival and proof of invasion status (i.e., recurrence or lymph node metastasis). The secondary outcome was the correlation with radiologic surrogates of tumor invasiveness (consolidation-to-tumor ratio and maximum standardized uptake value) and pathologic risk factors. RESULTS: The re-evaluation resulted in a 22% downstaging and 2.5% upstaging of pT, which improved the correlation with radiologic (consolidation-to-tumor ratio and maximum standardized uptake value) and pathologic risk factors. The revised pT staging allowed for more accurate discrimination of recurrence-free survival than the original pT staging (c-index = 0.794 versus 0.717). Moreover, the revised pT staging significantly improved the prediction of recurrence or lymph node metastasis (area under the curve = 0.818 versus 0.741, p < 0.001). CONCLUSIONS: To our knowledge, this is the first study evaluating the clinical significance of the IASLC-proposed criteria for invasion. The proposed IASLC criteria offered better alignment with clinicopathologic risk factors and improved prognostication. Further studies are warranted to assess the impact of the IASLC criteria on treatment decisions and patient outcomes.

Rheumatoid Arthritis and Risk of Lung Cancer: A Nationwide Cohort Study.

INTRODUCTION: There has been an increasing interest in the risk of lung cancer related to rheumatoid arthritis (RA). We investigated the association between RA and the risk of lung cancer with consideration of key confounding factors, including RA serostatus and smoking status. METHODS: Using a nationwide database, we identified 51,899 patients with newly diagnosed RA between 2010 and 2017, which were matched by sex and age at a 1:5 ratio with 259,495 non-RA population. The association of lung cancer and RA was investigated using Cox regression analyses. Stratified analyses by smoking status, sex, age, and comorbidity of interstitial lung disease were conducted using the same Cox modeling. RESULTS: During 4.5 years of follow-up, the adjusted hazard ratio of lung cancer in the patients with RA was 1.49 (95% confidence interval: 1.34-1.66). Compared with the patients with seronegative RA, an increased risk of lung cancer was not considerable in the patients with seropositive RA. In the stratified analyses, the increased risk of lung cancer was more prominent in current or previous heavy smokers with RA (interaction p value of 0.046) and male patients (interaction p < 0.001), whereas there was no substantial effect associated with age or interstitial lung disease status. CONCLUSIONS: Patients with RA had an increased risk of lung cancer compared with the non-RA group, and the risk did not differ by RA serostatus. There is a need for increased awareness of smoking cessation and potentially for regular lung cancer screening with proper risk stratification in patients with RA.