Mitigation of acute lung injury by human bronchial epithelial cell-derived extracellular vesicles via ANXA1-mediated FPR signaling.

Acute lung injury (ALI) is characterized by respiratory failure resulting from the disruption of the epithelial and endothelial barriers as well as immune system. In this study, we evaluated the therapeutic potential of airway epithelial cell-derived extracellular vesicles (EVs) in maintaining lung homeostasis. We isolated human bronchial epithelial cell-derived EVs (HBEC-EVs), which endogenously express various immune-related surface markers and investigated their immunomodulatory potential in ALI. In ALI cellular models, HBEC-EVs demonstrated immunosuppressive effects by reducing the secretion of proinflammatory cytokines in both THP-1 macrophages and HBECs. Mechanistically, these effects were partially ascribed to nine of the top 10 miRNAs enriched in HBEC-EVs, governing toll-like receptor-NF-κB signaling pathways. Proteomic analysis revealed the presence of proteins in HBEC-EVs involved in WNT and NF-κB signaling pathways, pivotal in inflammation regulation. ANXA1, a constituent of HBEC-EVs, interacts with formyl peptide receptor (FPR)2, eliciting anti-inflammatory responses by suppressing NF-κB signaling in inflamed epithelium, including type II alveolar epithelial cells. In a mouse model of ALI, intratracheal administration of HBEC-EVs reduced lung injury, inflammatory cell infiltration, and cytokine levels. Collectively, these findings suggest the therapeutic potential of HBEC-EVs, through their miRNAs and ANXA1 cargo, in mitigating lung injury and inflammation in ALI patients.

Clinical outcomes of left upper segmentectomy vs. lobectomy for early non-small-cell lung cancer: a nationwide database study in Japan.

PURPOSE: Given that left upper lobe and right upper and middle lobes share a similar anatomy, segmentectomy, such as upper division and lingulectomy, should yield identical oncological clearance to left upper lobectomy. We compared the prognosis of segmentectomy with that of lobectomy for early stage non-small-cell lung cancer (NSCLC) in the left upper lobe. METHODS: We retrospectively examined 2115 patients who underwent segmentectomy or lobectomy for c-stage I (TNM 8th edition) NSCLC in the left upper lobe in 2010. We compared the oncological outcomes of segmentectomy (n = 483) and lobectomy (n = 483) using a propensity score matching analysis. RESULTS: The 5-year recurrence-free and overall survival rates in the segmentectomy and lobectomy groups were comparable, irrespective of c-stage IA or IB. Subset analyses according to radiological tumor findings showed that segmentectomy yielded oncological outcomes comparable to those of lobectomy for non-pure solid tumors. In cases where the solid tumor exceeded 20 mm, segmentectomy showed a recurrence-free survival inferior to that of lobectomy (p = 0.028), despite an equivalent overall survival (p = 0.38). CONCLUSION: Segmentectomy may be an acceptable alternative to lobectomy with regard to the overall survival of patients with c-stage I NSCLC in the left upper lobe.

Prognostic factors in pulmonary metastases resection from colorectal cancer: impact of right-sided colon cancer and early recurrence.

OBJECTIVE: This retrospective cohort study aimed to explore the surgical outcomes and prognostic factors of resection of pulmonary metastases (PM) from colorectal cancer (CRC). METHODS: Overall, 60 patients who underwent resection of PM from CRC between 2015 and 2021 at two institutions were reviewed. The primary outcome were overall survival (OS) and early recurrence after PM resection. The association between OS and right-sided colon cancer (RCC) was investigated. Early recurrence after PM resection was defined as recurrence within one year. RESULTS: The 5-year OS after CRC resection was 83.8% (95% confidence interval [CI] 67.5-92.4) and after PM resection was 69.4% (95% CI 47.5-83.6). In total, 25 patients had recurrence after PM resection (16 within 1 year and 9 after 1 year). In multivariable analysis for OS, RCC (hazard ratio [HR] 4.370, 95% CI 1.020-18.73; p = 0.047) and early recurrence after resection of PM (HR 17.23, 95% CI 2.685-110.6; p = 0.003) were risk factors for poor OS. In multivariable analysis for early recurrence after PM resection, higher value of carcinoembryonic antigen (CEA) (> 5.0 mg/dL) before PM resection was a risk factor for early recurrence (HR 3.275, 95% CI 1.092-9.821; p = 0.034). CONCLUSION: The RCC and early recurrence after PM resection were poor prognosis factors of OS. Higher value of CEA before PM resection was an independent risk factor for early recurrence after resection of PM. Comparitive study between surgery and nonsurgery is necessary in patients with higher CEA values.

Dual-specificity tyrosine-regulated kinase 2 exerts anti-tumor effects by induction of G1 arrest in lung adenocarcinoma.

OBJECTIVES: Lung cancer is a leading cause of cancer-related mortality and remains one of the most poorly prognosed disease worldwide. Therefore, it is necessary to identify novel molecular markers with potential therapeutic effects. Recent findings have suggested that dual-specificity tyrosine-regulated kinase 2 (DYRK2) plays a tumor suppressive role in colorectal, breast, and hepatic cancers; however, its effect and mechanism in lung cancer remain poorly understood. Therefore, this study aimed to investigate the tumor-suppressive role and molecular mechanism of DYRK2 in lung adenocarcinoma (LUAD) by in vitro experiments and xenograft models. MATERIALS AND METHODS: The evaluation of DYRK2 expression was carried out using lung cancer cell lines and normal bronchial epithelial cells. Overexpression of DYRK2 was induced by an adenovirus vector, and cell proliferation was assessed through MTS assay and Colony Formation Assay. Cell cycle analysis was performed using flow cytometry. Additionally, proliferative capacity was evaluated in a xenograft model by subcutaneously implanting A549 cells into SCID mice (C·B17/Icr-scidjcl-scid/scid). RESULTS: Immunoblotting assays showed that DYRK2 was downregulated in most LUAD cell lines. DYRK2 overexpression using adenovirus vectors significantly suppressed cell proliferation compared with that in the control group. Additionally, DYRK2 overexpression suppressed tumor growth in a murine subcutaneous xenograft model. Mechanistically, DYRK2 overexpression inhibited the proliferation of LUAD cells via p21-mediated G1 arrest, which was contingent on p53. CONCLUSION: Taken together, these findings suggest that DYRK2 may serve as potential prognostic biomarker and therapeutic target for LUAD.

Compensatory expansion of the right middle lobe: volumetric and functional analysis of the changes after right upper or lower lobectomy.

The right middle lobe often poorly expands after right upper lobectomy. Postoperative pulmonary function may be inferior after right upper lobectomy than after right lower lobectomy due to poor expansion of the middle lobe. This study examined the difference in the postoperative right middle lobe expansion and pulmonary function between right upper and right lower lobectomy. Patients who underwent right upper or right lower lobectomy through video-assisted thoracic surgery (n = 82) were enrolled in this retrospective study. Pulmonary function tests and computed tomography were performed preoperatively and at 1 year postoperatively. Using three-dimensional computed tomography volumetry, the preoperative and postoperative lung volumes were measured, and the predicted postoperative forced expiratory volume in 1 s was calculated. Middle lobe volume ratio (i.e., ratio of the postoperative to the preoperative middle lobe volume) and the postoperative forced expiratory volume in 1 s ratio (i.e., ratio of the measured to the predicted postoperative forced expiratory volume in 1 s) were compared between right upper and right lower lobectomy. Compared with the patients who underwent right upper lobectomy (n = 50), those who underwent right lower lobectomy (n = 32) had significantly higher middle lobe volume ratio (1.15 ± 0.32 vs. 1.63 ± 0.52, p < 0.001) and postoperative forced expiratory volume in 1 s ratio (1.12 ± 0.12 vs. 1.19 ± 0.13, p = 0.010). The right middle lobe showed more expansion and better recovery of postoperative pulmonary function after right lower lobectomy than after right upper lobectomy.

Reduction in drain-related adverse events using the barbed suture method for chest tube wound closure.

OBJECTIVE: A chest tube is usually placed in patients undergoing general thoracic surgery. Although the barbed suture method has been introduced for chest tube wound closure, its superiority to the conventional suture methods for drain management remains unclear. The study aimed to determine whether the barbed suture method could reduce drain-related adverse events compared to the conventional method. METHODS: We retrospectively reviewed the medical records of patients who underwent general thoracic surgery between January 2021 and December 2022, 1 year before and after the introduction of the barbed suture method at our institution. Patients who underwent the barbed suture or conventional method were included. Univariate and multivariate analyses of drain-related adverse events were performed. RESULTS: Of the 250 participants, 110 and 140 underwent the barbed suture method and conventional suture method, respectively. The univariate analysis showed that a higher body mass index, preoperative malignant diagnosis, lobectomy, longer operative time, larger tube size, longer chest drainage duration, surgical complications, and conventional method were risk factors for drain-related adverse events. The multivariate analysis showed that the barbed suture method was a protective factor against drain-related adverse events (odds ratio 0.267; 95% confidence interval 0.103-0.691; P = 0.007). CONCLUSIONS: The barbed suture method could reduce drain-related adverse events compared to the conventional method. Therefore, it might be a potential standard method for chest tube wound closure in patients undergoing general thoracic surgery.

Weight loss of 5% or more after lobectomy for lung cancer via minimally invasive approaches is associated with poor prognosis.

INTRODUCTION: We analyzed the association between postoperative weight loss (WL), preoperative body mass index (BMI), and prognosis in patients with lung cancer who underwent lobectomy using minimally invasive approaches. METHODS: Weight change in 325 patients who underwent radical lobectomy for non-small cell lung cancer was assessed at 3, 6, and 12 months postoperatively and compared to preoperative weight. Patients were divided into three groups according to their preoperative BMI interquartile range: low BMI ≤20.3 kg/m2 , middle BMI 20.4-24.4 kg/m2 , and high BMI ≥24.5 kg/m2 . Postoperative WL ≥5% was evaluated with reference to frailty. RESULTS: There were no significant differences in pathological findings, postoperative complications, or postoperative hospital stay among the three groups. Thirty all-cause deaths and 39 cancer recurrences occurred. Within the first year after surgery, WL of any grade was observed in 229 patients (70.5%) and WL ≥5% in 86 patients (26.5%). Postoperative WL of any grade within 1 year after surgery was not associated with OS and RFS (both p > .05). However, WL ≥5% within 1 year after surgery was associated with worse OS and RFS (p = .007 and .006, respectively). WL ≥5% within 1 year after surgery was more common in the low BMI group (p = .045). There was no difference in OS and RFS among the BMI groups in patients with WL ≥5% and those without WL ≥5% (all p > .05). CONCLUSION: WL ≥5% was associated with poor prognosis after lobectomy via minimally invasive approaches. Weighing is a useful prognostic marker that can be easily self-checked.

Benefit of Adjuvant Chemotherapy for Patients Older Than 75 Years With Completely Resected p-Stage II-IIIA Non-Small-Cell Lung Cancer: A Retrospective Cohort Study Using Japanese Nationwide Real-World Data.

BACKGROUND: The efficacy of adjuvant chemotherapy (ACT) in elderly patients with completely resected p-stage II-IIIA non-small-cell lung cancer (NSCLC) remains unclear because all previous randomized controlled trials on ACT have been conducted among patients aged <75 years. Thus, this study aimed to evaluate the effectiveness of ACT in elderly patients with completely resected NSCLC. PATIENTS: We extracted the nationwide data of 812 patients aged ≥75 years who underwent lobectomy with mediastinal nodal dissection in 2010 and were diagnosed with p-stage II-IIIA NSCLC, from nationwide registry data accumulated in 2016. METHODS: We classified the 812 patients into 2 groups based on the ACT administration status and analyzed the differences in their postoperative overall survival (OS). RESULTS: Overall, 295 patients received ACT (36.3%; group A), whereas 517 patients did not (63.70%; group N). Group A showed significantly better OS as a whole (hazard ratio [HR]: 0.650 [95% confidence interval {CI}: 0.526-0.804]), in the p-stage II subset (HR: 0.688 [95% CI: 0.513-0.925]), and p-stage IIIA subset (HR: 0.547 [95% CI: 0.402-0.743]) than group N. Even after propensity score matching, group A showed significantly better OS as a whole (HR: 0.626 [95% CI: 0.495-0.792]), in the p-stage II subset (HR: 0.690 [95% CI: 0.493-0.964]), and p-stage IIIA subset (HR: 0.554 [95% CI: 0.398-0.772]) than group N. CONCLUSION: ACT is recommended even in elderly patients with completely resected p-stage II-IIIA NSCLC. Hence, physicians should not avoid ACT in patients with completely resected NSCLC based solely on age.

[Management of Postoperative Surgical Site Infection and Empyema After Thoracic Surgery].

Surgical site infections (SSI)[wound infection, empyema] after thoracic surgery can lead to severe complications. Targeted antibiotic treatment and drainage are the keys. For the treatment of postoperative empyema without bronchopleural fistula, chest tube thoracostomy and irrigation with normal saline is effective. For postoperative empyema with bronchopleural fistula, open window thoracotomy is a good treatment option. Since the condition of empyema is different in each patient, treatment should be individualized depending on the patient's condition.

Risk factors for the recurrence of primary spontaneous pneumothorax after video-assisted thoracoscopic surgery in patients younger than 40 years.

Background: Video-assisted thoracoscopic surgery (VATS) is a standard primary spontaneous pneumothorax (PSP) procedure. However, its high recurrence rate compared to open thoracotomy is a problem. Therefore, various methods to prevent recurrence have been developed. The present study investigated the risk factors for postoperative recurrence of PSP after VATS. Methods: From January 2008 to November 2022, 207 patients younger than 40 years of age without underlying pulmonary disease underwent thoracoscopic bullectomy for PSP. Among them, 96 underwent staple line reinforcement with a polyglycolic acid (PGA) sheet and autologous blood spraying. Patient characteristics and surgical outcomes were analyzed to determine the prognostic factors for postoperative recurrence. Results: Twenty-seven patients (13.0%) experienced recurrences. A multivariate analysis using Cox regression analysis revealed that age younger than 20 years [P=0.039; hazard ratio (HR) =2.337; 95% confidence interval (CI): 3.283-17.287], history of contralateral pneumothorax (P<0.001; HR =7.533; 95% CI, 1.486-12.336), and no staple line reinforcement (P=0.007; HR =4.282; 95% CI, 1.043-5.236) were risk factors for recurrence after pneumothorax surgery. Conclusions: Age younger than 20 years and history of contralateral pneumothorax were risk factors for postoperative recurrence of pneumothorax. Staple line reinforcement with a PGA sheet and spraying of autologous blood reduced the postoperative recurrence rate of PSP.

Is adjuvant chemotherapy for completely resected p-stage IA (>2 cm) and stage IB non-small-cell lung cancer beneficial for elderly patients? A large, retrospective cohort study based on real-world data from Japan.

OBJECTIVE: The efficacy of tegafur-uracil as adjuvant chemotherapy for patients with completely resected stage I non-small-cell lung cancer is proven; however, its efficacy for elderly patients remains unclear. Herein, we evaluated the effectiveness of adjuvant chemotherapy for elderly patients with completely resected stage I non-small-cell lung cancer based on real-world Japanese data using propensity score matching. METHODS: This retrospective study extracted data from a nationwide registry study, performed in 2016, on patients ≥75 years who underwent lobectomy with mediastinal nodal dissection for non-small-cell lung cancer in 2010 and were diagnosed with p-stage IA (>2 cm) or stage IB non-small-cell lung cancer. We classified the 1294 patients into two groups-Group A, postoperative adjuvant chemotherapy (n = 295, 22.8%) and Group N, no adjuvant chemotherapy (n = 999, 77.2%)-and analyzed differences in postoperative overall survival between groups. RESULTS: Group A showed no advantage in overall survival over Group N as a whole (hazard ratio: 0.824 [95% confidence interval: 0.631-1.076]), in p-stage IA (hazard ratio: 0.617 [95% confidence interval: 0.330-1.156]) and in p-stage IB (hazard ratio: 0.806 [95% confidence interval: 0.597-1.088]) subsets. Even after propensity score matching, Group A showed no significant advantage in overall survival over Group N as a whole (hazard ratio: 0.975 [95% confidence interval: 0.688-1.381]), in p-stage IA (hazard ratio: 1.390 [95% confidence interval: 0.539-3.586]) and in p-stage IB (hazard ratio: 0.922 [95% confidence interval: 0.633-1.343]). CONCLUSIONS: adjuvant chemotherapy for completely resected p-stage IA (>2 cm) and stage IB non-small-cell lung cancer showed no benefit for recommendation for elderly patients; considering the risk of adverse events, we do not recommend adjuvant chemotherapy for elderly patients.

Features of anaplastic lymphoma kinase rearrangement in early-stage lung cancer: Analysis of a nationwide Japanese database.

BACKGROUND AND OBJECTIVES: Anaplastic lymphoma kinase (ALK) rearrangement is a representative driver mutation in lung cancer. However, the biology of early-stage ALK-rearranged lung cancer remains unclear. We aimed to assess the clinicopathological features, prognostic implications, and influence of ALK rearrangement on the postoperative course in surgically resected lung cancer. METHODS: We retrospectively analyzed data from the Japanese Joint Committee of Lung Cancer Registry database. Of the 12 730 patients with lung adenocarcinoma, 794 (6.2%) were tested for ALK rearrangement and were included. RESULTS: ALK rearrangements were detected in 76 patients (10%). The 5-year overall survival (OS) rate was significantly higher in the ALK rearrangement-positive group than in the ALK rearrangement-negative group (p = 0.030). Multivariable analysis revealed that ALK rearrangement was an independent prognostic factor for improved OS (hazard ratio, 0.521; 95% confidence interval, 0.298-0.911; p = 0.022). Regarding the postrecurrence state, there was no difference in the initial recurrence sites between both groups. Administration of ALK-tyrosine kinase inhibitors (TKIs) improved postrecurrence survival in any treatment lines. CONCLUSION: In one of the largest national surveys, ALK rearrangement was associated with improved long-term outcomes in surgically resected patients. ALK-TKIs may be an important treatment strategy for ALK rearrangement-positive lung adenocarcinoma in the postrecurrence state.

Prognostic Impact of Visceral Pleural Invasion in Resected Solitary Lung Metastases from Gastric Cancer.

PURPOSE: Pulmonary resection of metastases from gastric cancer is extremely rare because gastric cancer metastasis to the lungs or thoracic cavity occurs as multiple pulmonary metastases, carcinomatous lymphangitis, or carcinomatous pleurisy. Therefore, the significance of surgery for pulmonary metastasis of gastric cancer remains unclear. This study aimed to investigate the surgical outcomes and prognostic factors for survival after the resection of pulmonary metastases from gastric cancer. METHODS: From 2007 to 2019, 13 patients with pulmonary metastasis of gastric cancer underwent metastasectomy. Surgical outcomes were analyzed to determine the prognostic factors for recurrence and overall survival (OS). RESULTS: All the patients underwent pulmonary resection for solitary metastases. At the median follow-up time of 45.6 months (range, 4.8-106.8 months), five patients experienced a recurrence of gastric cancer after metastasectomy. The 5-year recurrence-free survival rate was 44.4%, and the 5-year OS rate after pulmonary resection was 45.3%. Univariate analysis revealed that visceral pleural invasion (VPI) was an unfavorable prognostic factor for both recurrence-free and OS. CONCLUSION: Pulmonary resection of solitary metastases from gastric cancer may be an effective therapeutic option to improve survival. VPI in gastric cancer metastasis is a negative prognostic factor.

Pulmonary metastases of a borderline ovarian tumor with multiple cystic formations: a case report.

BACKGROUND: Metastatic lung tumors rarely present with cystic formations. This is the first report of multiple cystic formations in pulmonary metastases from mucinous borderline ovarian tumors written in English. CASE PRESENTATION: A 41-year-old woman underwent left adnexectomy + partial omentectomy + para-aortic lymphadenectomy for a left ovarian tumor 4 years ago. The pathological finding was mucinous borderline ovarian tumor with a microinvasion. A chest computed tomography performed 3 years after surgery revealed multiple cystic lesions in both lungs. After 1-year follow-up, the cysts increased in size and wall thickness. Subsequently, she was referred to our department with multiple cystic lesions in both lungs. No laboratory findings indicated infectious diseases or autoimmune disorders that could cause cystic lesions in both lungs. Positron emission tomography showed slight accumulation in the cyst wall. Partial resection of the left lower lobe was performed to confirm the pathological diagnosis. The diagnosis was consistent with pulmonary metastases from a previous mucinous borderline ovarian tumor. CONCLUSIONS: This is a rare case of lung metastases from a mucinous borderline ovarian tumor presenting with multiple lesions with cystic formation. Pulmonary cystic formations in patients with a borderline ovarian tumor should be considered as possible pulmonary metastases.

Fibroblast-derived Extracellular Vesicles Induce Lung Cancer Progression in the Idiopathic Pulmonary Fibrosis Microenvironment.

Idiopathic pulmonary fibrosis (IPF) is a progressive aging-related lung disease associated with increased lung cancer risk. Although previous studies have shown that IPF worsens the survival of patients with lung cancer, whether IPF independently affects cancer malignancy and prognosis remains inconclusive. Extracellular vesicles (EVs) have recently emerged as active carriers of molecular biomarkers and mediators of intercellular communication in lung homeostasis and pathogenesis. EV cargo-mediated fibroblast-tumor cell communication might participate in the development and progression of lung cancer by modulating various signaling pathways. In this study, we examined the impact of lung fibroblast (LF)-derived EVs on non-small cell lung cancer (NSCLC) malignancy in the IPF microenvironment. Here, we showed that LFs derived from patients with IPF have phenotypes of myofibroblast differentiation and cellular senescence. Furthermore, we found that IPF LF-derived EVs have markedly altered microRNA compositions and exert proproliferative functions on NSCLC cells. Mechanistically, the phenotype was attributed mainly to the enrichment of miR-19a in IPF LF-derived EVs. As a downstream signaling pathway, mir-19a in IPF LF-derived EVs regulates ZMYND11-mediated c-Myc activation in NSCLC, potentially contributing to the poor prognosis of patients with NSCLC with IPF. Our discoveries provide novel mechanistic insights for understanding lung cancer progression in the IPF microenvironment. Accordingly, blocking the secretion of IPF LF-derived EV miR-19a and their signaling pathways is a potential therapeutic strategy for managing IPF and lung cancer progression.

Comparative study of local versus general anesthesia in video-assisted thoracoscopic surgery for empyema.

OBJECTIVE: This study evaluated the feasibility of performing non-intubated video-assisted thoracoscopic surgery (VATS) with local anesthesia for parapneumonic effusion and empyema resistant to conservative treatment. METHODS: We retrospectively reviewed 80 patients who underwent surgery for parapneumonic effusions and empyema between 2015 and 2021. Patients were divided into those who received non-intubated local anesthesia and general anesthesia during surgery. Patient demographics, characteristics, laboratory findings, treatment progress, and treatment outcomes were compared. The primary outcomes were duration of postoperative drainage, postoperative complication rate, and postoperative mortality rate within 30 days. RESULTS: Among patients who received local (n = 21) and general anesthesia (n = 59), there was a significant difference in age (median 79.0 years [interquartile range (IQR) 77.0-80.0] vs. 68.0 years [IQR 54.5-77.5]; p < 0.001), preoperative performance status (3.0 [IQR 2.0-4.0] vs. 2.0 [IQR 1.0-3.0]; p < 0.001), and operative time (69 min [IQR 50-128] vs. 150 min [IQR 107-198]; p < 0.001) but not in preoperative white blood cell count (12,100/µL [IQR 8,400-18000] vs. 12,220/µL [IQR 8,950-16,724]; p = 0.840), C-reactive protein (15.2 mg/dL [8.8-21.3] vs. 17.9 mg/dL [IQR 9.5-23.6]; p = 0.623), postoperative drainage period (11 days [IQR 7-14] vs. 9 days [7-13]; p = 0.216), postoperative hospital stay (22 days [IQR 16-53] vs. 18 days [IQR 12-26]; p = 0.094), reoperation rate (9.5% vs. 15.3%; p = 0.775), postoperative complication rate (19.0% vs. 18.6%; p = 0.132), or postoperative 30-day mortality rate (4.8% vs. 0%; p = 0.587). CONCLUSIONS: VATS using local anesthesia is feasible for patients with treatment-resistant parapneumonic effusion and empyema with poor general condition.

Postoperative surveillance using low-dose computed tomography for non-small-cell lung cancer.

OBJECTIVES: We retrospectively analysed the surgical prognosis of patients with pathological stage I non-small-cell lung cancer (NSCLC) who after complete resection underwent low-dose computed tomography (LDCT) or conventional CT as postoperative surveillance. METHODS: We investigated 416 patients who underwent lobectomy or segmentectomy between January 2013 and December 2016. We compared the prognosis between the LDCT and conventional CT groups using the propensity score-matched analysis. RESULTS: The median follow-up period was 57 months. Cancer recurrence occurred in 47 patients (11.3%). In the entire cohort (n = 416), recurrence-free survival (RFS) and overall survival (OS) were better in the LDCT group (P = 0.001 and 0.002, respectively). Both intrathoracic recurrence and distant metastasis were higher in the conventional group (P = 0.015 and 0.009, respectively). However, there was no statistical difference in the factors leading to recurrence detection (routine radiological examination, symptoms and elevated tumour markers: all P > 0.05). Both groups were matched using a ratio of 1:1. The area under the receiver operating characteristic curve was 0.788. A total of 226 patients were successfully matched. After matching, there was no statistical difference between the 2 groups for RFS and OS (P = 0.263 and 0.226). There were also no statistical differences in recurrence rate, the factors leading to recurrence detection or recurrence site (all P > 0.05). CONCLUSIONS: After using propensity score matched, RFS and OS did not differ significantly between LDCT and conventional CT groups. Retrospective comparisons suggest no disadvantages of using LDCT for postoperative surveillance of pathological stage I NSCLC. Further validation will be needed in the future.