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.

Safety and efficacy of new staple-line reinforcement in lung resection: a prospective study of 48 patients.

PURPOSE: To evaluate the safety and efficacy of new staple-line reinforcement (SLR) in pulmonary resection through a prospective study and to compare the results of this study with historical control data in an exploratory study. METHODS: The subjects of this study were 48 patients who underwent thoracoscopic lobectomy. The primary endpoint was air leakage from the staple line. The secondary endpoints were the location of air leakage, duration of air leakage, and postoperative pulmonary complications. RESULTS: The incidence of intraoperative air leakage from the staple line was 6.3%. Three patients had prolonged air leakage as a postoperative pulmonary complication. No malfunction was found in patients who underwent SLR with the stapling device. When compared with the historical group, the SLR group had a significantly lower incidence of air leakage from the staple line (6.3% vs. 28.5%, P < 0.001) and significantly shorter indwelling chest drainage time (P = 0.049) and length of hospital stay (P < 0.001). CONCLUSIONS: The use of SLR in pulmonary resection was safe and effective. When compared with conventional products, SLR could control intraoperative air leakage from the staple line and shorten time needed for indwelling chest drainage and the length of hospital stay.

Factors affecting the short-term outcomes of robotic-assisted thoracoscopic surgery for lung cancer.

PURPOSE: Robotic-assisted thoracoscopic surgery (RATS) is a relatively new approach to lung cancer surgery. To promote the development of RATS procedures, we investigated the factors related to short-term postoperative outcomes. METHODS: We analyzed the records of patients who underwent RATS lobectomy for primary lung cancer at our institution between June, 2018 and January, 2023. The primary outcome was operative time, and the estimated value of surgery-related factors was calculated by linear regression analysis. The secondary outcome was surgical morbidity and the risk was assessed by logistic regression analysis. RESULTS: The study cohort comprised 238 patients. Left upper lobectomy had the longest mean operative time, followed by right upper lobectomy. Postoperative complications occurred in 13.0% of the patients. Multivariate analysis revealed that upper lobectomy, the number of staples used for interlobular fissures, and the number of cases experienced by the surgeon were significantly associated with a longer operative time. The only significant risk factor for postoperative complications was heavy smoking. CONCLUSION: Patients with well-lobulated middle or lower lobe lung cancer who are not heavy smokers are recommended for the introductory period of RATS lobectomy. Improving the procedures for upper lobectomy and dividing incomplete interlobular fissures will promote the further development of RATS.

[Perioperative Strategy of Fluid and Nutrition in the Compromised Patients After Lung Resection].

The strategy for the administration of fluid and nutrition management after lung resection is not unusual, as compared to the other ordinal surgeries. However, it should be kept in mind that relative reduction in right ventricular function could occur following lung resection due to increased pulmonary vascular resistance. The surgical trauma such as pulmonary arterial clamp and lymphadenectomy as well as the removal of the lung, and perioperative factors such as single lung ventilation, could also increase pulmonary vascular resistance, all of which could be related to acute lung injury. Regarding the fluid management, excessive fluid administration could cause pulmonary edema, decreased alveolar gas permeability, atelectasis, and hypoxia, while restrictive fluid management could induce complication related to hypoperfusion. Since these adverse effects are highly associated with the main causes of morbidity and mortality particularly in the compromised patients, a proper assessment and monitoring of fluid balance (fluid optimization) would be required. In addition, along with the increasing number of the elderly patients, particular concerns must be given to the patients with the sarcopenia or frailty. The appropriate nutritional support following lung surgery is necessary to reduce surgical morbidity and morbidity especially for the malnourished and elderly patients.

Exploration of a novel prognostic model based on nomogram in non-small cell lung cancer patients with distant organ metastasis: implications for immunotherapy.

Background: Evidence for the effects of immunotherapy in non-small cell lung cancer (NSCLC) patients with distant organ metastasis is insufficient, and the predictive efficacy of established markers in tissue and blood is elusive. Our study aimed to determine the prognostic factors and develop a survival prognosis model for these patients. Methods: A total of 100 advanced NSCLC patients with distant organ metastases, who received single or combination immune checkpoint inhibitors (ICIs) in Xijing Hospital between June 2018 and June 2021, were enrolled for retrospective analysis. The major clinicopathological parameters were collected, and associated survival outcomes were followed up by telephone or inpatient follow-up for nearly 3 years to assess prognoses. The survival prognosis model was established based on univariate and multivariate Cox regression analyses to determine the candidate prognostic factors. Results: From the start of immunotherapy to the last follow-up, 77 patients progressed and 42 patients died, with a median follow-up of 18 months [95% confidence interval (CI): 15-19.9]. The median progression-free survival (PFS) and overall survival (OS) were 8 months (95% CI: 5.6-10.4) and 21 months (95% CI: 8.9-33.1), respectively. Multivariate Cox proportional hazards analysis showed Eastern Cooperative Oncology Group performance status (ECOG PS), body mass index (BMI), age-adjusted Charlson comorbidity index (ACCI), lactate dehydrogenase (LDH), and absolute neutrophil count (ANC) were correlated significantly with OS. Based on these five predictive factors, a nomogram and corresponding dynamic web page were constructed with a concordance index (C-index) of 0.81 and a 95% CI of 0.778-0.842. Additionally, the calibration plot and time-receiver operating characteristic (ROC) curve validated the precision of the model at 6-, 12-, and 18-month area under the curves (AUCs) reached 0.934, 0.829, and 0.846, respectively. According to the critical point of the model, patients were further divided into a high-risk total point score (TPS) >258, middle-risk (204< TPS ≤258), and low-risk group (TPS ≤204), and significant OS differences were observed among the three subgroups (median OS: 4.8 vs. 13.0 vs. 32.9 months). Conclusions: A feasible and practical model based on clinical characteristics has been developed to predict the prognosis of NSCLC patients with distant organ metastasis undergoing immunotherapy.

Console and bedside surgeon fused robot-assisted thoracic surgery.

In the last decade, even thoracic surgery has seen an increase in the use of robotic surgical systems, and robot-assisted thoracic surgery (RATS) is considered one of the main issues. While RATS is associated with solo manipulative freedom and high-definition optical systems, several disadvantages, such as the lack of tactile sensation and difficult learning curves for the whole team, have been raised. Therefore, to overcome these issues, we developed a 'fusion surgery' approach combining a robotic procedure with manual maneuvers, where the table surgeon retracts the lung and staples the pulmonary vasculature and bronchus. Herein, we introduce our 'fusion surgery' procedure and elaborate on its advantage from technical and educational perspectives.

Programmed death ligand-1 expression and occult lymph node metastasis in non-small cell lung cancer.

BACKGROUND: Identifying the preoperative risk factors for lymph node upstaging could contribute to the development of individualized perioperative treatment for patients with non-small cell lung cancer (NSCLC). The current study aimed to evaluate the risk factors for lymph node upstaging, including gene mutation and programmed death ligand-1 expression in patients with resectable NSCLC. METHODS: Data on the clinicopathological characteristics of patients who underwent lobectomy for clinical N0 NSCLC at our institution were collected. The clinicopathological findings of the pathological N0 and lymph node upstaging groups were then analyzed. Univariate and multivariate analyses were performed to examine the predictive factors for nodal upstaging. RESULTS: Of 291 patients, 40 had postoperative nodal upstaging (n = 25, N1; n = 15, N2). Large tumor size and high maximum standardized uptake value were significantly associated with nodal upstaging. The nodal upstaging group had a higher proportion of patients with solid adenocarcinoma and lymphatic, vascular, and pleural invasion than the pathological N0 group. Further, the nodal upstaging group had a higher proportion of patients with positive programmed death ligand-1 expression than the pathological N0 group. Univariate and multivariate analyses showed that tumor size and positive programmed death ligand-1 expression were associated with nodal upstaging. CONCLUSION: The appropriate therapeutic strategy including preoperative treatment and resection should be cautiously considered preoperatively in patients with clinical N0 NSCLC who have large tumors and positive programmed death ligand-1 expression.

Uniportal left S1 + 2 segmentectomy.

The left upper lobe is one of the largest lobes of the lung; left upper segmentectomy is well established among thoracic surgeons. In uniportal left S1 + 2 segmentectomy, dissection of the vasculature, bronchus, and intersegmental plane can be performed anteriorly. Given that the fissureless technique is commonly used in uniportal video-assisted thoracoscopic surgery, S1 + 2 segmentectomy exhibits high affinity with the unidirectional approach. We have frequently performed left S1 + 2 segmentectomy for early non-small cell lung cancer located in the apical segment, since this procedure has the potential to preserve pulmonary function over tri-segmentectomy. Herein, we introduce our approach to uniportal left S1 + 2 segmentectomy as a minimally invasive alternative for preserving lung function.

The dynamic pulmonary functional change after thoracoscopic lower lobe segmentectomy.

BACKGROUND: The advantages of segmentectomy over lobectomy in sparing pulmonary function remain controversial. Lower lobe segmentectomy is divided into simple segmentectomy, such as segment 6; and complex segmentectomy that includes the basal segments. Here, we compared residual lung function after thoracoscopic segmentectomy versus lobectomy in the lower lobe using the three-dimensional computed tomography volumetric method. METHODS: Between January 2012 and October 2020, 67 patients who underwent thoracoscopic segmentectomy of the lower lobe were matched to 67 patients who underwent thoracoscopic lower lobectomy during the same period using propensity score matching analysis. The postoperative decrease in the rate of forced expiratory volume in 1 s was compared between methods. The regional forced expiratory volume in 1 s of the residual lobe rescued by segmentectomy was measured using volumetric and spirometric analyses and compared to lower lobectomy. The ratio of the actual to predicted postoperative forced expiratory volume in 1 s in the residual lobe was defined as the preservation rate. RESULTS: Of the 67 thoracoscopic segmentectomies, 43 were S6, seven were S8, three were S8 + 9, seven were S10, and seven were S9 + 10. The percentage of postoperative/preoperative forced expiratory volume in 1 s was significantly higher in the segmentectomy versus lobectomy group (90.7% vs. 85.7%, p = 0.001). The preservation rates after simple segmentectomy (n = 43) and complex segmentectomy (n = 24) did not differ significantly (82.2% vs. 80.2%, p = 0.709). CONCLUSIONS: Thoracoscopic lower lobe segmentectomy versus lobectomy preserves postoperative lung function. Even complex segmentectomy exhibited outcomes relevant to simple segmentectomy by sparing the residual lobe.

Segmental volumetric analysis with a ventilated or perfused area: identifying the intersegmental plane.

OBJECTIVES: Two methods are available to identify the intersegmental plane during segmentectomy: the inflation-deflation method, based on the ventilation area, and injection of indocyanine green, based on the pulmonary arterial distribution. However, whether the intersegmental plane created by these 2 methods matches remains unknown. Our goal was to identify the demarcation lines based on bronchial and arterial territories using 3-dimensional computed tomography-based volumetry. METHODS: We collected data from patients who underwent thoracoscopic segmentectomy in our hospital between April 2012 and May 2021. Three-dimensional images were reconstructed from the preoperative contrast-enhanced computed tomography data using the SYNAPSE VINCENT software program. The volume of the affected area and the distance of the tumour from the intersegmental plane were calculated based on each affected artery and bronchus. Each calculated volume was compared to each affected segment using a paired t-test. RESULTS: Of 195 patients, 114 underwent upper lobe segmentectomy, and 81 underwent lower lobe segmentectomy. In upper lobe segmentectomy, the affected arterial segmental volume was smaller than the bronchial volume (505.0 ml vs 539.4 ml, P < 0.001). In lower lobe segmentectomy, there was no significant difference between arterial and bronchial volumes (234.6 ml vs 236.9 ml, P = 0.607). The volume of the affected arterial segmental lung and the distance of the tumour from the intersegmental plane were significantly smaller than the bronchial volume in upper lobe segmentectomies. CONCLUSIONS: As per the results, the affected segmental volume delineated by the indocyanine green method would be underestimated in upper lobe segmentectomy.

Segmentectomy versus lobectomy for inner-located small-sized early non-small-cell lung cancer.

OBJECTIVES: Although segmentectomy is an acceptable alternative to lobectomy for peripheral small-sized non-small-cell lung cancer, the effectiveness of segmentectomy for inner lesions remains unknown. The aim of this study was to examine the feasibility of segmentectomy in comparison with lobectomy for inner lesions. METHODS: We retrospectively analysed 570 patients with small (≤2 cm) cN0 non-small-cell lung cancer who underwent segmentectomy or lobectomy between January 2007 and March 2021. We focused on patients with lesions located in the inner two-thirds, which were determined using three-dimensional computed tomography (n = 227). After propensity score matching analysis based on sex, age, pulmonary function, serum carcinoembryonic antigen level, radiographic tumour findings and tumour location, we compared the surgical and oncological outcomes in patients who underwent segmentectomy (n = 66) and lobectomy (n = 66). RESULTS: Postoperative mortality or morbidity did not differ significantly between the 2 groups. The 5-year recurrence-free and overall survival rates in the segmentectomy and lobectomy groups were 93.6% vs 84.1% and 95.8% vs 87.9%, respectively. The differences between 2 groups were not significant (P = 0.62 and P = 0.23, respectively). The 2 groups also showed no differences in loco-regional recurrence. Multivariable Cox regression analysis revealed that segmentectomy had a comparable impact on recurrence-free survival (hazard ratio, 0.61; 95% confidence interval, 0.17-2.03; P = 0.43). CONCLUSIONS: Segmentectomy for inner-located small-sized non-small-cell lung tumours could be an acceptable treatment in comparison with lobectomy.

Resected stage I anaplastic lymphoma kinase-positive lung adenocarcinoma has a negative impact on recurrence-free survival.

BACKGROUND: The clinical and prognostic implications of anaplastic lymphoma kinase (ALK) status in resected lung cancers remain unclear. In this study we analyzed the prognostic and predictive significance of ALK-positive among patients with completely resected lung adenocarcinoma. METHODS: We retrospectively reviewed 197 patients with lung adenocarcinoma who underwent complete surgical resection and had been tested for their ALK status. We investigated the impact of an ALK-positive status on the recurrence-free survival (RFS) and overall survival (OS) and examined the predictive factors for an ALK-positive status. RESULTS: ALK positivity was noted in 36 (18%) out of 197 patients, and when limited to stage I patients, in 24 (19%) out of 124. In the pathological-stage I population, while the OS exhibited no significant difference between ALK-positive and ALK-negative patients (5-year OS rate, 81.2% vs. 89.8%, p = 0.226), the RFS of ALK-positive patients was significantly worse than that of ALK-negative patients (5-year RFS rate, 55.9% vs. 78.8%, p = 0.018). A multivariate analysis showed that ALK-positive status (hazard ratio [HR] 3.431, p = 0.009) was an independent prognostic factor for the RFS. Regarding the relationship between clinicopathological factors and an ALK-positive status, a high-grade histological subtype, including solid and micropapillary subtypes (odds ratio [OR] 5.464, p < 0.001), and never-smokers (OR 4.292, p = 0.018) were associated with ALK-positive. CONCLUSION: A high-grade histological subtype and never-smokers were associated with ALK positivity, and the RFS of ALK-positive patients was worse than that of ALK-negative patients among patients with completely resected stage I lung adenocarcinoma.

Basal segment deep wedge resection for lung cancer with pulmonary fibrosis.

Acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) is among the most fatal postoperative complications of lung resection in patients with IPF. Non-small-cell lung cancer (NSCLC) with IPF exhibits basal segment dominance. Treatment options for these lesions include lobectomy or basal segment segmentectomies. However, these procedures potentially increase risks of AE due to surgical stress including prolonged operative time and loss of pulmonary function. Therefore, as an alternative to these procedures, we developed a simple and practical deep wedge resection technique for basal segments. Our technique is minimally invasive and quick and simple approach in patients with NSCLC and IPF.

The difference in postoperative pulmonary functional change between upper and lower thoracoscopic lobectomy.

OBJECTIVES: Through 3-dimensional lung volumetric and morphological analyses, we aimed to evaluate the difference in postoperative functional changes between upper and lower thoracoscopic lobectomy. METHODS: A total of 145 lung cancer patients who underwent thoracoscopic upper lobectomy (UL) were matched with 145 patients with lung cancer who underwent thoracoscopic lower lobectomy (LL) between April 2012 and December 2018, based on their sex, age, smoking history, operation side, and pulmonary function. Spirometry and computed tomography were performed before and 6 months after the operation. In addition, the postoperative pulmonary function, volume and morphological changes between the 2 groups were compared. RESULTS: The rate of postoperative decreased and the ratio of actual to predicted postoperative forced expiratory volume in 1 s were significantly higher after LL than after UL (P < 0.001 for both). The tendency above was similar irrespective of the resected side. The postoperative actual volumes of the ipsilateral residual lobe and contralateral lung were larger than the preoperatively measured volumes in each side lobectomy. Moreover, the increased change was particularly remarkable in the middle lobe after right LL. The change in the D-value, representing the structural complexity of the lung, was better maintained in the left lung after LL than after UL (P = 0.042). CONCLUSIONS: Pulmonary function after thoracoscopic LL was superior to that after UL because the upward displacement and the pulmonary reserves of the remaining lobe appeared more robust after LL.

Segmentectomy for Inner Location Small-Sized Non-Small Cell Lung Cancer: Is It Feasible?

BACKGROUND: The efficacy of segmentectomy for inner small-sized non-small-cell lung cancer (NSCLC) remains unknown. We aimed to elucidate whether segmentectomy for inner small-sized NSCLC, defined using a novel 3-dimensional measuring method, yields feasible oncologic outcomes compared with segmentectomy for outer lesions. METHODS: We retrospectively analyzed patients with small-sized (<2 cm) cN0 NSCLC who underwent segmentectomy between January 2007 and December 2020. The tumor centrality ratio, which was measured by using 3-dimensional reconstruction software, was evaluated. The location of tumor origin was confirmed pathologically. Cases with a ratio <2:3 and >2:3 were allocated to the inner group and outer group, respectively. Oncologic outcomes were compared between the 2 groups. RESULTS: Our cohort was divided into the inner group (n = 75) and outer group (n = 127). The proximal distance from a tumor was >20 mm in all cases. The tumor centrality ratio was associated with the pathologic origin of a tumor. The rate of unforeseen positive lymph node metastasis was significantly higher in the inner group (P = .04). There were no significant differences in the 5-year recurrence-free survival (91% vs 87%, P = .67). Univariate analysis identified age, consolidation/tumor ratio, the presence of ground-glass opacity, and lymphovascular invasion, but not tumor centrality, as significant prognostic factors for recurrence-free survival. In the multivariate analysis, the presence of ground-glass opacity and lymphovascular invasion remained significant. CONCLUSIONS: Regarding oncologic outcomes, segmentectomy with a safety proximal distance could be feasible, even for inner small-sized NSCLC. Tumor invasiveness, not tumor centrality, may influence tumor recurrence.

Comparison of oncological outcomes between trisegmentectomy and lobectomy for non-small cell lung cancer in the left upper division.

Background: The left upper lobe is one of the largest lobes in the lungs and is divided into two anatomical units: the upper division (segments 1+2 and segment 3) and lingula (segments 4 and 5). This anatomical classification is similar to that used for the right upper and middle lobes. Although bilobectomy is not recommended for right upper or middle lobe tumors close to the interlobar plane, lobectomy is often performed for tumors located close to the intersegmental plane in the left upper division. To aid in establishing trisegmentectomy as a standard treatment for clinical N0 non-small cell lung cancer (NSCLC) in the left upper lobe, we aimed to re-assess its feasibility based on oncological outcomes according to tumor location. Methods: We retrospectively analyzed the data of patients with clinical N0 NSCLC in the left upper division who underwent left upper lobectomy or trisegmentectomy between April 2006 and December 2020. After propensity score matching, oncological outcomes were compared between the trisegmentectomy and lobectomy groups. To verify whether trisegmentectomy was indicated regardless of tumor distance from the intersegmental plane, we compared the recurrence-free survival (RFS) rates following trisegmentectomy between patients with tumors ≤20 and >20 mm from the intersegmental plane. Results: After propensity score matching, 46 patients were included in each group. There was no significant difference in the 5-year RFS rate between the lobectomy and trisegmentectomy groups (75.5% vs. 84.0%, P=0.41). In the trisegmentectomy cohort, the 5-year RFS rate did not significantly differ according to tumor distance from the intersegmental plane (≤20 or >20 mm) measured using three-dimensional computed tomography (79.4% vs. 81.2%, P=0.69). Multivariate analysis indicated that tumor distance from the intersegmental plane was not a significant predictor of RFS (hazard ratio: 1.75, 95% confidence interval: 0.52-5.91, P=0.37). Conclusions: Our analysis suggests that oncological outcomes (i.e., RFS rates) following trisegmentectomy for clinical N0 NSCLC in the left upper division are not significantly inferior to those following lobectomy, even if the tumor is located close to the intersegmental plane.

Cellular cannibalism and consequent thrombocytopenia in a patient with bone marrow metastasis of malignant pleural mesothelioma: A case report.

Cellular cannibalism is a tumor activity where a cell is engulfed by another cell. This process promotes tumor cell survival under unfavorable conditions. The current report describes an extremely rare case of thrombocytopenia resulting from cellular cannibalism in a patient with bone marrow metastasis due to malignant pleural mesothelioma (MPM). A 77-year-old male presented with hemothorax and thrombocytopenia. He was diagnosed with MPM of the sarcomatoid cell type. However, his disease progressed rapidly and he died 11 days after admission. Bone marrow aspiration revealed metastatic MPM cells that had engulfed other blood cells. Accordingly, the observed thrombocytopenia was attributed to cellular cannibalism by metastatic MPM tumor cells. To the best of our knowledge, this is the first reported case of thrombocytopenia due to cellular cannibalism in a patient with this type of malignancy (MPM). The results suggested that although MPM rarely metastasizes to the bone marrow, bone marrow aspiration could be useful in such cases.

Prognostic significance of preoperative haemoglobin A1c level in patients with lung adenocarcinoma.

OBJECTIVES: We investigated the influence of the preoperative haemoglobin A1c (HbA1c) value on the prognosis and pathology of patients with lung adenocarcinoma who underwent surgery. METHODS: We reviewed the medical records of 400 lung adenocarcinoma patients who underwent lobectomy with mediastinal lymph node dissection between 2009 and 2013 using a prospectively maintained database. We stratified 400 patients into 4 groups according to the preoperative HbA1c value as follows: HbA1c ≤ 5.9 (n = 296), 6.0 ≤ HbA1c ≤ 6.9 (n = 70), 7.0 ≤ HbA1c ≤ 7.9 (n = 21) and HbA1c ≥ 8.0 (n = 12). We compared the recurrence-free survival and overall survival (OS) among these 4 groups. Univariate and multivariate analyses were performed to identify the risk factors for recurrence. RESULTS: The median follow-up period was 61.2 months. On comparing the recurrence-free survival and OS rates among these 4 groups, we found that these rates among patients in the HbA1c ≥ 8.0 group were significantly poorer compared with the other 3 groups (5-year recurrence-free survival: HbA1c ≤ 5.9, 70.4%; 6.0 ≤ HbA1c ≤ 6.9, 69.7%; 7.0 ≤ HbA1c ≤ 7.9, 70.7%; ≥8.0 HbA1c, 18.8%; P = 0.002; and 5-year OS: HbA1c ≤ 5.9, 88.7%; 6.0 ≤ HbA1c ≤ 6.9, 80.6%; 7.0 ≤ HbA1c ≤ 7.9, 90.2%; ≥8.0 HbA1c, 66.7%; P = 0.046). Patients in the HbA1c ≥ 8.0 group had significantly more tumours with vascular invasion (P = 0.041) and experienced distant metastasis significantly more often (P = 0.028) than those with other values. A multivariate analysis revealed that preoperative HbA1c ≥ 8.0 [hazard ratio (HR) 2.33; P = 0.026] and lymph node metastasis (HR 3.94; P < 0.001) were significant independent prognostic factors for recurrence. CONCLUSIONS: Our results revealed that preoperative HbA1c ≥ 8.0 is associated to poor prognosis due to the occurrence of distant metastasis and we should carefully follow these patients after surgery. CLINICAL REGISTRATION NUMBER: Hyogo Cancer Center, G-57.

Cluster analysis of emphysema for predicting pulmonary complications after thoracoscopic lobectomy.

OBJECTIVES: Despite significant advances in surgical techniques, including thoracoscopic approaches and perioperative care, the morbidity rate remains high after lung resection. This study focused on a low attenuation cluster analysis, which represented the size distribution of pulmonary emphysema and assessed its utility for predicting postoperative pulmonary complications after thoracoscopic lobectomy. METHODS: From April 2013 to September 2018, lung cancer patients who received spirometry and computed tomography (CT) before surgery and underwent thoracoscopic lobectomy were included. The cumulative size distribution of the low attenuation area (LAA, defined as ≤-950 Hounsfield unit on CT) clusters followed a power-law characterized by an exponent D-value, a measure of the complexity of the alveolar structure. D-value and LAA% (LAA/total lung volume) were calculated using preoperative 3-dimensional CT software. The relationship between pulmonary complications and patient characteristics, including D-value and LAA%, was investigated. RESULTS: Among 471 patients, there were 61 respiratory complication cases (12.9%). Receiver operation characteristic curve analysis revealed that the best predictive cut-off value of D-value and LAA% for pulmonary complications was 2.27 and 16.5, respectively, with an area under the curve of 0.72 and 0.58, respectively. D-value was significantly correlated with % forced expiratory volume in 1 s. Per univariate analysis, gender, smoking history, forced expiratory volume in 1 s/forced vital capacity, LAA% and D-value were risk factors for predicting postoperative pulmonary complications. In the multivariate analysis, D-value remained a significant predictive factor. CONCLUSION: Preoperative assessment of emphysema cluster analysis may represent the vulnerability of the operated lung and could be the novel predictor for pulmonary complications after thoracoscopic lobectomy.