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.

Purpose: Programmed death-1/programmed death-ligand 1 (PD-L1) inhibitors have shown efficacy in metastatic esophageal squamous cell carcinoma (ESCC) therapy. However, data is still limited regarding neoadjuvant immunotherapy for operable ESCC. Materials and Methods: Patients with clinical stage T2 or T3 and N0 ESCC received three cycles of nivolumab therapy every two weeks before surgical resection. The primary endpoint is major pathologic responses (MPR) rate (≤ 10% of residual viable tumor [RVT]). Results: Total 20 patients completed the planned nivolumab therapy. Among them, 17 patients underwent surgery as protocol, showing MPR in two patients (MPR rate, 11.8%), including one pathologic complete response, on conventional pathologic response evaluation. Pathologic response was re-evaluated using the immune-related pathologic response criteria based on immune-related RVT (irRVT). Three patients were classified as immunologic major pathologic response (iMPR; ≤ 10% irRVT, iMPR rate: 17.6%), five as pathologic partial response (> 10% and < 90% irRVT), and nine as pathologic nonresponse (≥ 90% irRVT). The combined positive score (CPS) for PD-L1 in the baseline samples was predictable for iMPR, with the probability as 37.5% in CPS ≥ 10 (3/8) and 0% in CPS < 10 (0/9). Conclusion Although the efficacy of neoadjuvant nivolumab therapy was modest in unselected ESCC patients, further researches on neoadjuvant immunotherapy are necessary in patients with PD-L1 expressed ESCC.

Purpose: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors have greatly improved survival in EGFR-mutant (EGFRm) non–small cell lung cancer (NSCLC); however, their effects on the tumor microenvironment (TME) are unknown. We assessed the changes induced by neoadjuvant erlotinib therapy (NE) in the TME of operable EGFRm NSCLC. Materials and Methods: This was a single-arm phase II trial for neoadjuvant/adjuvant erlotinib therapy in patients with stage II/IIIA EGFRm NSCLC (EGFR exon 19 deletion or L858R mutations). Patients received up to 2 cycles of NE (150 mg/day) for 4 weeks, followed by surgery and adjuvant erlotinib or vinorelbine plus cisplatin therapy depending on observed NE response. TME changes were assessed based on gene expression analysis and mutation profiling. Results: A total of 26 patients were enrolled; the median age was 61, 69% were female, 88% were stage IIIA, and 62% had L858R mutation. Among 25 patients who received NE, the objective response rate was 72% (95% confidence interval [CI], 52.4 to 85.7). The median disease-free and overall survival (OS) were 17.9 (95% CI, 10.5 to 25.4) and 84.7 months (95% CI, 49.7 to 119.8), respectively. Gene set enrichment analysis in resected tissues revealed upregulation of interleukin, complement, cytokine, transforming growth factor β, and hedgehog pathways. Patients with upregulated pathogen defense, interleukins, and T-cell function pathways at baseline exhibited partial response to NE and longer OS. Patients with upregulated cell cycle pathways at baseline exhibited stable/progressive disease after NE and shorter OS. Conclusion NE modulated the TME in EGFRm NSCLC. Upregulation of immune-related pathways was associated with better outcomes.

Purpose: Recently, we developed allele-discriminating priming system (ADPS) technology. This method increases the sensitivity of conventional quantitative polymerase chain reaction up to 100 folds, with limit of detection, 0.01%, with reinforced specificity. This prospective study aimed to develop and validate the accuracy of ADPS epidermal growth factor receptor (EGFR) Mutation Test Kit using clinical specimens. Materials and Methods: In total 189 formalin-fixed paraffin-embedded tumor tissues resected from patients with non–small cell lung cancer were used to perform a comparative evaluation of the ADPS EGFR Mutation Test Kit versus the cobas EGFR Mutation Test v2, which is the current gold standard. When the two methods had inconsistent results, next-generation sequencing–based CancerSCAN was utilized as a referee. Results: The overall agreement of the two methods was 97.4% (93.9%-99.1%); the positive percent agreement, 95.0% (88.7%-98.4%); and the negative percent agreement, 100.0% (95.9%-100.0%). EGFR mutations were detected at a frequency of 50.3% using the ADPS EGFR Mutation Test Kit and 52.9% using the cobas EGFR Mutation Test v2. There were 10 discrepant mutation calls between the two methods. CancerSCAN reproduced eight ADPS results. In two cases, mutant allele fraction was ultra-low at 0.02% and 0.06%, which are significantly below the limit of detection of the cobas assay and CancerSCAN. Based on the EGFR genotyping by ADPS, the treatment options could be switched in five patients. Conclusion The highly sensitive and specific ADPS EGFR Mutation Test Kit would be useful in detecting the patients who have lung cancer with EGFR mutation, and can benefit from the EGFR targeted therapy.

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 2 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%), nine (26%), and four (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 5-year DFS rate of 29%. The OS rate was 86% at 2 years and 76% at 5 years. Patients with tumor recurrence within 6 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.

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.

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.

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.

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.

Purpose: This multi-center, retrospective study was conducted to evaluate the long-term survival in patients who underwent surgical resection for small cell lung cancer (SCLC) and to identify the benefit of adjuvant therapy following surgery. Materials and Methods: The data of 213 patients who underwent surgical resection for SCLC at four institutions were retrospectively reviewed. Patients who received neoadjuvant therapy or an incomplete resection were excluded. Results: The mean patient age was 65.29±8.93 years, and 184 patients (86.4%) were male. Lobectomies and pneumonectomies were performed in 173 patients (81.2%), and 198 (93%) underwent systematic mediastinal lymph node dissections. Overall, 170 patients (79.8%) underwent adjuvant chemotherapy, 42 (19.7%) underwent radiotherapy to the mediastinum, and 23 (10.8%) underwent prophylactic cranial irradiation. The median follow-up period was 31.08 months (interquartile range, 13.79 to 64.52 months). The 5-year overall survival (OS) and disease-free survival were 53.4% and 46.9%, respectively. The 5-year OS significantly improved after adjuvant chemotherapy in all patients (57.4% vs. 40.3%, p=0.007), and the survival benefit of adjuvant chemotherapy was significant in patients with negative node pathology (70.8% vs. 39.7%, p=0.004). Adjuvant radiotherapy did not affect the 5-year OS (54.6% vs. 48.5%, p=0.458). Age (hazard ratio [HR], 1.032; p=0.017), node metastasis (HR, 2.190; p < 0.001), and adjuvant chemotherapy (HR, 0.558; p=0.019) were associated with OS. Conclusion Adjuvant chemotherapy after surgical resection in patients with SCLC improved the OS, though adjuvant radiotherapy to the mediastinum did not improve the survival or decrease the locoregional recurrence rate.