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.

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.

Deep learning model integrating cfDNA methylation and fragment size profiles for lung cancer diagnosis

Detecting aberrant cell-free DNA (cfDNA) methylation is a promising strategy for lung cancer diagnosis. In this study, our aim is to identify methylation markers to distinguish patients with lung cancer from healthy individuals. Additionally, we sought to develop a deep learning model incorporating cfDNA methylation and fragment size profiles. To achieve this, we utilized methylation data collected from The Cancer Genome Atlas and Gene Expression Omnibus databases. Then we generated methylated DNA immunoprecipitation sequencing and genome-wide Enzymatic Methyl-seq (EM-seq) form lung cancer tissue and plasma. Using these data, we selected 366 methylation markers. A targeted EM-seq panel was designed using the selected markers, and 142 lung cancer and 56 healthy samples were produced with the panel. Additionally, cfDNA samples from healthy individuals and lung cancer patients were diluted to evaluate sensitivity. Its lung cancer detection performance reached an accuracy of 81.5% and an area under the receiver operating characteristic curve of 0.87. In the serial dilution experiment, we achieved tumor fraction detection of 1% at 98% specificity and 0.1% at 80% specificity. In conclusion, we successfully developed and validated a combination of methylation panel and a deep learning model that can distinguish between patients with lung cancer and healthy individuals.

Computed tomography characteristics of cN0 primary non-small cell lung cancer predict occult lymph node metastasis

RATIONALE

Occult lymph node metastasis (OLNM) is frequently found in patients with resectable non-small cell lung cancer (NSCLC), despite using diagnostic methods recommended by guidelines.

OBJECTIVES

To evaluate the risk of OLNM in NSCLC patients using the radiologic characteristics of the primary tumor on computed tomography (CT).

METHODS

We retrospectively reviewed clinicopathologic features of 2042 clinical T1-4N0 NSCLC patients undergoing curative intent pulmonary resection. Unique radiological features (i.e., air-bronchogram throughout the whole tumor, heterogeneous ground-glass opacity (GGO), mainly cystic appearance, endobronchial location), percentage of solid portion, and shape of tumor margin were analyzed via a stepwise approach. We used multivariable logistic regression to assess the relationship between OLNM and tumor characteristics.

RESULTS

Compared with the other unique features, endobronchial tumors were associated with the highest risk of OLNM (OR = 3.9, 95% confidence interval (CI) = 2.29-6.62), and heterogeneous GGO and mainly cystic tumors were associated with a low risk of OLNM. For tumors without unique features, the percentage of the solid portion was measured, and solid tumors were associated with OLNM (OR = 2.49, 95% CI = 1.86-3.35). Among part-solid tumors with solid proportion > 50%, spiculated margin, and peri-tumoral GGO were associated with OLNM.

CONCLUSIONS

The risk of OLNM could be assessed using radiologic characteristics on CT. This could allow us to adequately select optimal candidates for invasive nodal staging procedures (INSPs) and complete systematic lymph node dissection.

CLINICAL RELEVANCE STATEMENT

These data may be helpful for clinicians to select appropriate candidates for INSPs and complete surgical systematic lymph node dissection in NSCLC patients.

KEY POINTS

Lymph node metastasis status plays a key role in both prognostication and treatment planning. Solid tumors, particularly endobronchial tumors, were associated with occult lymph node metastasis (OLNM). The risk of OLNM can be assessed using radiologic characteristics acquired from CT images.

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.

Clinical and Pathologic Supraclavicular Lymph Node Metastases in Esophageal Squamous Cell Carcinoma Treated by Esophagectomy with Three-Field Lymph Node Dissection

BACKGROUND

This study investigated the survival outcomes for surgically treated esophageal squamous cell carcinoma (ESCC) patients based on clinically suspicious supraclavicular lymph node (SCN) metastasis (cSCN+) and pathologically confirmed SCN metastasis (pSCN+).

METHODS

Using an institutional registry between 1994 and 2018, this study retrospectively analyzed 611 patients who received curative-intent esophagectomy with 3-field lymph node dissection for ESCC. The study used computed tomography and positron emission tomography to define cSCN+.

RESULTS

Among 611 patients, 24.4% had cSCN+ and 12.2% had pSCN+. The 5-year overall survival (OS) rates were 68.2% for cN0, 43.5% for cN+ without cSCN+, and 30.3% for cN+ with cSCN+ (p = 0.018). Although the univariable analysis showed that cSCN+ was associated with poorer survival than cN0 or cN+ with cSCN- (hazard ratio [HR], 1.818; p < 0.001), the multivariable analysis did not support this finding (HR, 1.281; p = 0.681). The 5-year OS rates were 64.2% for pN0, 41.5% for pN+ without pSCN+, and 25.6% for pN+ with pSCN+ (p = 0.054). Univariable analysis showed an association of pSCN+ with poor OS (HR, 1.830; p < 0.001), but the difference in the multivariable analysis was not significant (HR, 0.912; p = 0.587).

CONCLUSIONS

The presence of SCN metastasis did not have a significant impact on the OS of ESCC patients with 3-field lymph node dissection regardless of clinical suspicion or pathologic confirmation.

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.

Adjuvant Pembrolizumab in Patients with Stage IIIA/N2 Non-Small Cell Lung Cancer Completely Resected after Neoadjuvant Concurrent Chemoradiation: A Prospective, Open-Label, Single-Arm, Phase 2 Trial

Purpose

Optimal treatment for stage IIIA/N2 non-small cell lung cancer (NSCLC) is controversial. We aimed to assess the efficacy and safety of adjuvant pembrolizumab for stage IIIA/N2 NSCLC completely resected after neoadjuvant concurrent chemoradiation therapy (CCRT).

Materials and Methods

In this open-label, single-center, single-arm phase 2 trial, patients with stage IIIA/N2 NSCLC received adjuvant pembrolizumab for up to two years after complete resection following neoadjuvant CCRT. The primary endpoint was disease-free survival (DFS). Secondary endpoints included overall survival (OS) and safety. As an exploratory biomarker analysis, we evaluated the proliferative response of blood CD39+PD-1+CD8+ T cells using fold changes in the percentage of proliferating Ki-67+ cells from days 1 to 7 of cycle 1 (Ki-67D7/D1).

Results

Between October 2017 and October 2018, 37 patients were enrolled. Twelve (32%) and three (8%) patients harbored EGFR and ALK alterations, respectively. Of 34 patients with programmed cell death ligand 1 assessment, 21 (62%), 9 (26%), and 4 (12%) had a tumor proportion score of <1%, 1-50%, and ≥50%, respectively. The median follow-up was 71 months. The median DFS was 22.4 months in the overall population, with a five-year DFS rate of 29%. The OS rate was 86% at two years and 76% at five years. Patients with tumor recurrence within six months had a significantly lower Ki-67D7/D1 among CD39+PD-1+CD8+ T cells than those without (p=0.036). No new safety signals were identified.

Conclusion

Adjuvant pembrolizumab may offer durable disease control in a subset of stage IIIA/N2 NSCLC patients after neoadjuvant CCRT and surgery.

Metabolic dysfunction-associated steatotic liver disease and risk of esophageal cancer in patients with diabetes mellitus: a nationwide cohort study

Metabolic dysfunction-associated steatotic liver disease (MASLD) is closely associated with type 2 diabetes and a developing several cancers including esophageal cancer (EC). However, the association between MASLD and EC in diabetic patients has not been investigated. Therefore, we aimed to investigate the relation between MASLD and developing EC in diabetic patients. This was a population-based retrospective cohort study of data from the Korean National Health Insurance Service (NHIS). A total of 1,904,468 subjects diagnosed with diabetes who underwent NHIS-provided health checkups from 2009 to 2012 were included. We constructed a Cox proportional hazard model for the association of fatty liver index (FLI) and the risk of EC stratified by potential confounders. Over a mean follow-up duration of 6.9 years, the incidence of EC was higher in the high (≥60) FLI group compared to the low (<30) FLI group (14.4 vs. 13.7 event per 100,000 person-years). The risk of EC correlated with the degree of FLI, particularly in older (P = 0.002), female (P = 0.033), non-smoking (P = 0.002), and non-drinking patients (P = 0.025). Among obese patients, the risk of EC was not associated with FLI; however, the risk of EC was higher in the high FLI group in non-obese patients. Lean MASLD patients had the highest risk of EC (adjusted hazard ratio 1.78; 95% confidence interval, 1.5-2.13). MASLD was associated with an increased risk of EC in diabetic patients, and lean MASLD has the highest risk. Further studies are required to determine the causal relationship between MASLD and EC.

Comprehensive analysis of transcription factor-based molecular subtypes and their correlation to clinical outcomes in small-cell lung cancer

BACKGROUND

Recent studies have reported the predictive and prognostic value of novel transcriptional factor-based molecular subtypes in small-cell lung cancer (SCLC). We conducted an in-depth analysis pairing multi-omics data with immunohistochemistry (IHC) to elucidate the underlying characteristics associated with differences in clinical outcomes between subtypes.

METHODS

IHC (n = 252), target exome sequencing (n = 422), and whole transcriptome sequencing (WTS, n = 189) data generated from 427 patients (86.4% males, 13.6% females) with SCLC were comprehensively analysed. The differences in the mutation profile, gene expression profile, and inflammed signatures were analysed according to the IHC-based molecular subtype.

FINDINGS

IHC-based molecular subtyping, comprised of 90 limited-disease (35.7%) and 162 extensive-disease (64.3%), revealed a high incidence of ASCL1 subtype (IHC-A, 56.3%) followed by ASCL1/NEUROD1 co-expressed (IHC-AN, 17.9%), NEUROD1 (IHC-N, 12.3%), POU2F3 (IHC-P, 9.1%), triple-negative (IHC-TN, 4.4%) subtypes. IHC-based subtype showing high concordance with WTS-based subtyping and non-negative matrix factorization (NMF) clusterization method. IHC-AN subtype resembled IHC-A (rather than IHC-N) in terms of both gene expression profiles and clinical outcomes. Favourable median overall survival was observed in IHC-A (15.2 months) compared to IHC-N (8.0 months, adjusted HR 2.3, 95% CI 1.4-3.9, p = 0.002) and IHC-P (8.3 months, adjusted HR 1.7, 95% CI 0.9-3.2, p = 0.076). Inflamed tumours made up 25% of cases (including 53% of IHC-P, 26% of IHC-A, 17% of IHC-AN, but only 11% of IHC-N). Consistent with recent findings, inflamed tumours were more likely to benefit from first-line immunotherapy treatment than non-inflamed phenotype (p = 0.002).

INTERPRETATION

This study provides fundamental data, including the incidence and basic demographics of molecular subtypes of SCLC using both IHC and WTS from a comparably large, real-world Asian/non-Western patient cohort, showing high concordance with the previous NMF-based SCLC model. In addition, we revealed underlying biological pathway activities, immunogenicity, and treatment outcomes based on molecular subtype, possibly related to the difference in clinical outcomes, including immunotherapy response.

FUNDING

This work was supported by AstraZeneca, Future Medicine 2030 Project of the Samsung Medical Center [grant number SMX1240011], the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) [grant number 2020R1C1C1010626] and the 7th AstraZeneca-KHIDI (Korea Health Industry Development Institute) oncology research program.

Clinical Effect of Endosonography on Overall Survival in Patients with Radiological N1 Non-Small Cell Lung Cancer

PURPOSE

It is unclear whether performing endosonography first in non-small cell lung cancer (NSCLC) patients with radiological N1 (rN1) has any advantages over surgery without nodal staging. We aimed to compare surgery without endosonography to performing endosonography first in rN1 on the overall survival (OS) of patients with NSCLC.

MATERIALS AND METHODS

This is a retrospective analysis of patients with rN1 NSCLC between 2013 and 2019. Patients were divided into 'no endosonography' and 'endosonography first' groups. We investigated the effect of nodal staging through endosonography on OS using propensity score matching (PSM) and multivariable Cox proportional hazard regression analysis.

RESULTS

In the no endosonography group, pathologic N2 occurred in 23.0% of patients. In the endosonography first group, endosonographic N2 and N3 occurred in 8.6% and 1.6% of patients, respectively. Additionally, 51 patients were pathologic N2 among 249 patients who underwent surgery and mediastinal lymph node dissection (MLND) in endosonography first group. After PSM, the 5-year OSs were 68.1% and 70.6% in the no endosonography and endosonography first groups, respectively. However, the 5-year OS was 80.2% in the subgroup who underwent surgery and MLND of the endosonography first group. Moreover, in patients receiving surgical resection with MLND, the endosonography first group tended to have a better OS than the no endosonography group in adjusted analysis using various models.

CONCLUSION

In rN1 NSCLC, preoperative endosonography shows better OS than surgery without endosonography. For patients with rN1 NSCLC who are candidates for surgery, preoperative endosonography may help improve survival through patient selection.

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.

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.

Treatment Patterns and Outcomes of Anastomotic Leakage after Esophagectomy for Esophageal Cancer

Background

Anastomotic leakage (AL) following esophagectomy represents a serious complication that often results in prolonged hospitalization and necessitates repeated interventions, including nothing-by-mouth (NPO) restriction, endoscopic vacuum therapy (EVT), or surgical repair. In this study, we evaluated the patterns and outcomes of AL treatment.

Methods

We retrospectively reviewed the medical records of patients who underwent esophagectomy for esophageal cancer at a single center between 2003 and 2020. Of 3,096 examined cases, 181 patients (5.8%) with AL were included in the study: 114 patients (63%) with cervical anastomosis (CA) and 67 (37%) with intrathoracic anastomosis (TA).

Results

The incidence of AL was 11.9% in the CA and 3.2% in the TA group (p<0.001). Among patients with CA who developed AL, 87 (76.3%) were managed with NPO, 15 (13.2%) with EVT, and 12 (10.5%) with surgical repair. Over 90% of patients with cervical AL resumed an oral diet by the time of discharge, regardless of treatment method. Among patients with TA and AL, 36 (53.7%) received NPO, 25 (37.7%) underwent EVT, and 6 (9%) required surgery. Of these, 34 patients who were managed with NPO and 19 with EVT could resume an oral diet. However, only 2 patients who underwent surgery resumed an oral diet, and 2 patients required additional EVT.

Conclusion

Although patients with CA displayed a higher incidence of AL, their rate of successful oral intake exceeded that of those with TA, regardless of treatment method. Among patients exhibiting AL with TA, EVT was more commonly employed than in CA cases, and it appears effective.

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.

Role of invasive mediastinal nodal staging in survival outcomes of patients with non-small cell lung cancer and without radiologic lymph node metastasis: a retrospective cohort study

Background

Lung cancer diagnostic guidelines advocate for invasive mediastinal nodal staging (IMNS), but the survival benefits of this approach in patients with non-small cell lung cancer (NSCLC) without radiologic evidence of lymph node metastasis (rN0) remain uncertain. We aimed to investigate the impact of IMNS in patients with rN0 NSCLC by comparing the long-term survival between patients who underwent IMNS and those who did not (non-IMNS).

Methods

In this retrospective cohort study, we included patients with NSCLC but without radiologic evidence of lymph node metastasis from the Registry for Thoracic Cancer Surgery and the clinical data warehouse at the Samsung Medical Centre, Republic of Korea between January 2, 2008 and December 31, 2016. We compared the 5-year overall survival (OS) rate as the primary outcome after propensity score matching between the IMNS and non-IMNS groups. The age, sex, performance statue, tumor size, centrality, solidity, lung function, FDG uptake in PET-CT, and histological examination of the tumor before surgery were matched.

Findings

A total of 4545 patients (887 in the IMNS group and 3658 in the non-IMNS group) who received curative treatment for NSCLC were included in this study. By the mediastinal node dissection, the overall incidence of unforeseen mediastinal node metastasis (N2) was 7.2% (317/4378 patients). Despite the IMNS, 67% of pathological N2 was missed (61/91 patients with unforeseen N2). Based on propensity score matching, 866 patients each for the IMNS and non-IMNS groups were assigned. There was no significant difference in 5-year OS and recurrence-free survival (RFS) between two groups: 5-year OS was 73.9% (95% confidence interval, CI: 71%-77%) for IMNS and 71.7% (95% CI: 68.6%-74.9%; p = 0.23), for non-IMNS (hazard ratio, HR 0.90, 95% CI: 0.77-1.07), while 5-year RFS was 64.7% (95% CI: 61.5%-68.2%) and 67.5% (95% CI: 64.3%-70.9%; p = 0.35 (HR 1.08, 95% CI: 0.92-1.27), respectively. Moreover, the timing and locations of recurrence were similar in both groups.

Interpretation

IMNS might not be required before surgery for patients with NSCLC without LN suspicious of metastasis. Further randomised trials are required to validate the findings of the present study.

Funding

None.

Importance of Lymph Node Evaluation in ≤2-cm Pure-Solid Non-Small Cell Lung Cancer

BACKGROUND

The prevalence of lymph node (LN) metastasis in small-sized lung cancer varies depending on the tumor size and proportion of ground-glass opacity. We investigated occult LN metastasis and prognosis in patients with small-sized non-small cell lung cancer (NSCLC), mainly focusing on the pure-solid tumor.

METHODS

We retrospectively reviewed patients with ≤2-cm clinical N0 NSCLC who underwent lung resection with curative intent from 2003 to 2017. Among them we analyzed patients who also underwent adequate complete systematic LN dissection. Pathologic results and disease-free survival of the radiologically mixed ground-glass nodule (mGGN) and pure-solid nodule (PSN) groups were analyzed.

RESULTS

Of 1329 patients analyzed, 591 had mGGNs and PSNs. As tumor size increased, patients in the mGGN group showed no difference in LN metastasis: ≤1 cm, 2.27%; 1.0 to 1.5 cm, 2.19%; and 1.5 to 2.0 cm, 2.18% (P = .999). However the PSN group showed a significant difference in LN metastasis as the tumor size increased: ≤1 cm, 2.67%; 1.0 to 1.5 cm, 12.46%; and 1.5 to 2.0 cm, 21.31% (P < .001). In the multivariate analysis tumor size was a significant predictor of nodal metastasis in the PSN group but not in the mGGN group. In terms of 5-year disease-free survival, the mGGN group showed a better prognosis than the PSN group (94.4% vs 71.2%, P < .001).

CONCLUSIONS

We need to conduct a thorough LN dissection during surgery for small-sized NSCLC, especially for pure-solid tumors ≥ 1 cm.