Risk Factors for Recurrence of Stage I Epidermal Growth Factor Receptor Mutated Lung Adenocarcinoma

BACKGROUND

We aimed to clarify the risk factors for postoperative recurrence in patients with epidermal growth factor receptor (EGFR)-mutated stage I lung adenocarcinoma, using EGFR wild-type adenocarcinoma as a comparator, to select optimal candidates for adjuvant therapy with EGFR tyrosine kinase inhibitor (TKI).

METHODS

Data of patients with pathologic stage I EGFR-mutated (n = 713) and wild-type (n = 673) adenocarcinoma who did not receive adjuvant therapy were retrospectively analyzed. The cumulative incidence of recurrence (CIR) was estimated using Gray's method, and multivariable Fine-Gray competing risk models identified independent risk factors associated with recurrence.

RESULTS

The CIR did not differ significantly between patients with EGFR-mutated and wild-type adenocarcinoma (P = .32). Multivariable analysis revealed that greater size (cm) of invasive tumor (hazard ratio 1.539; 95% CI, 1.077-2.201), lymphovascular invasion (hazard ratio 5.180; 95% CI, 2.208-12.15), pleural invasion (hazard ratio 3.388; 95% CI, 1.524-7.533), and high-grade histologic subtype (hazard ratio 4.295; 95% CI, 1.539-11.99) were independent risk factors for recurrence in patients with EGFR-mutated adenocarcinoma. The 5-year CIR was significantly higher among patients with these factors (tumor size greater than 2 cm, 15.9%; lymphovascular invasion, 26.9%; pleural invasion, 39.3%; and high-grade subtype, 44.4%) than among patients without them (4.4%, 2.2%, 3.9%, and 5%, respectively; P < .001). For patients with EGFR wild-type adenocarcinoma, independent risk factors for recurrence were invasive tumor size, lymphovascular invasion, and pleural invasion, but not histologic subtypes.

CONCLUSIONS

Even for patients with EGFR-mutated stage I lung adenocarcinoma, recurrence risk is stratified. Adjuvant therapy may be considered if they have high-risk factors for recurrence.

Omitting Lymph Node Dissection for Small Ground-Glass Opacity-Dominant Tumors

BACKGROUND

The purpose of this study was to determine the optimal extent of lymph node dissection required in patients with small (≤3 cm) radiologically ground-glass opacity-dominant, peripheral, non-small cell lung cancer tumors.

METHODS

The study analyzed the clinicopathologic findings and surgical outcomes of 988 patients with radiologic, ground-glass opacity-dominant non-small cell lung cancer without lymph node involvement who underwent complete resection of the primary tumor between 2010 and 2020. Patients were followed up for 54.5 months (median). Kaplan-Meier curves and the log-rank test were used in statistical analyses of the prognosis.

RESULTS

Median age, whole tumor size, solid tumor size, and maximum standardized uptake values were 68 years, 1.7 cm, 0.4 cm, and 0.9, respectively. Sixty percent of the cohort was female (n = 590). Wedge resection, segmentectomy, and lobectomy were performed in 206, 372, and 410 patients, respectively. A total of 982 of 988 (99%) tumors were adenocarcinomas. One patient had hilar lymph node involvement; however, no mediastinal lymph node metastasis or hilar or mediastinal lymph node recurrence was detected. The 5-year overall survival rate was 96.5% (95% CI, 94.8%-97.7%). Excellent survival outcomes were achieved regardless of procedure (wedge resection, 94.7% [95% CI, 89.1%-97.5%]; segmentectomy, 96.9% [95% CI, 93.7%-98.5%]; and lobectomy, 97.1% [95% CI, 94.4%-98.5%]).

CONCLUSIONS

Omitting lymph node dissection may be acceptable with curative intent for small tumors with radiologic ground-glass opacity dominance. Appropriate surgical procedures such as wedge resection, segmentectomy, or lobectomy can provide satisfactory outcomes in patients with indolent tumors if surgical margins are secured.

Rare but clinically important salivary gland-type tumor of the lung: A review

Salivary gland-type tumor (SGT) of the lung, which arises from the bronchial glands of the tracheobronchial tree, was first recognized in the 1950s. SGT represents less than 1% of all lung tumors and is generally reported to have a good prognosis. Mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ACC) are the two most common subtypes, comprising more than 90% of all SGTs. The reported 5-year survival rate of patients with SGT is 63.4%. Because this type of tumor develops in major bronchi, patients with SGT commonly present with symptoms of bronchial obstruction, including dyspnea, shortness of breath, wheezing, and coughing; thus, the tumor is usually identified at an early stage. Most patients are treated by lobectomy and pneumonectomy, but bronchoplasty or tracheoplasty is often needed to preserve respiratory function. Lymphadenectomy in the surgical resection of SGT is recommended, given that clinical benefit from lymphadenectomy has been reported in patients with MEC. For advanced tumors, appropriate therapy should be considered according to the subtype because of the varying clinicopathologic features. MEC, but not ACC, is less likely to be treated with radiation therapy because of its low response rate. Although previous researchers have learned much from studying SGT over the years, the diagnosis and treatment of SGT remains a complex and challenging problem for thoracic surgeons. In this article, we review the diagnosis, prognosis, and treatment (surgery, chemotherapy, and radiotherapy) of SGT, mainly focusing on MEC and ACC. We also summarize reports of adjuvant and definitive radiation therapy for ACC in the literature.

Tumor distance from the mediastinum predicts N2 upstaging in clinical stage I lower-lobe non-small cell lung cancer

OBJECTIVE

Pulmonary lymphatic drainage of the lower lobe into the mediastinal lymph nodes includes not only the pathway via the hilar lymph nodes but also the pathway directly into the mediastinum via the pulmonary ligament. This study aimed to determine the association between the distance from the mediastinum to the tumor and the frequency of occult mediastinal nodal metastasis (OMNM) in patients with clinical stage I lower-lobe non-small cell lung cancer (NSCLC).

METHODS

Between April 2007 and March 2022, data of patients who underwent anatomical pulmonary resection and mediastinal lymph node dissection for clinical stage I radiological pure-solid lower-lobe NSCLC were retrospectively reviewed. In computed tomography axial sections, the ratio of the distance from the inner edge of the lung to the inner margin of the tumor within the lung width of the affected lung was defined as the inner margin ratio. Patients were divided into 2 groups based on whether the inner margin ratio was ≤0.50 (inner-type) or >0.50 (outer-type), and the association between inner margin ratio status and clinicopathological findings was assessed.

RESULTS

In total, 200 patients were enrolled in the study. OMNM frequency was 8.5%. More inner-type than outer-type patients had OMNM (13.2% vs 3.2%; P = .012) and skip N2 metastasis (7.5% vs 1.1%; P = .038). Multivariable analysis revealed that the inner margin ratio was the only independent preoperative predictor of OMNM (odds ratio, 4.72; 95% CI, 1.31-17.07; P = .018).

CONCLUSIONS

Tumor distance from the mediastinum was the most important preoperative predictor of OMNM in patients with lower-lobe NSCLC.

Clinical Significance of Preserving Pulmonary Function After Lung Resection in Early-Stage Non-Small-Cell Lung Cancer

INTRODUCTION

To determine the association between changes in pulmonary function before and after surgery, and the subsequent prognosis, of patients with early-stage non-small-cell lung cancer (NSCLC).

METHODS

A total of 485 patients who underwent lobectomy or segmentectomy for NSCLC with whole tumor size ≤2 cm and clinical stage IA at 2 institutions were retrospectively reviewed. The relationship between the postoperative reduction rate in vital capacity (VC), forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1) and overall survival (OS) was investigated. OS determined the cut-off value of the reduction rate, according to the reduction rate of every 10% in pulmonary function.

RESULTS

Multivariable Cox regression analysis showed that a reduction rate in VC at 12 months postoperatively was an independent prognostic factor for OS (hazard ratio, 1.05; 95% confidence interval [CI], 1.02-1.07; P < .001) but those in FVC and FEV1 were not. OS was classified into good and poor with 20% reduction rate in VC. OS and recurrence-free survival (RFS) in a higher than 20% reduction rate in VC were worse than those in ≤20% reduction rate in VC (5 year-OS; 82.0% vs. 93.4%; P = .0004. Five year-RFS; 80.3% vs. 89.8%; P = .0018, respectively). Multivariable logistic analysis showed that lobectomy was a risk factor for the higher than 20% reduction rate in VC (odds ratio, 1.61; 95% CI, 1.01-2.56; P = .045).

CONCLUSIONS

Postoperative decrease in VC was significantly associated with the prognosis. Preserving pulmonary function is important for survival of patients with early-stage NSCLC.

Sublobar Resection in Early Non-Small Cell Lung Cancer With Epidermal Growth Factor Receptor Mutant

BACKGROUND

Lobectomy is a standard surgical procedure for peripherally located early-stage non-small cell lung cancers (NSCLCs) measuring 2 to 4 cm. However, it is unclear whether sublobar resections, such as wedge resection and segmentectomy, are effective in treating tumors with driver mutations in the epidermal growth factor receptor (EGFR).

METHODS

We analyzed the clinicopathologic findings and surgical outcomes of 1395 patients with radiologically solid-dominant NSCLC measuring 2 to 4 cm, without clinical lymph node involvement, who underwent complete resection between 2010 and 2020. The patients, who underwent sublobar resections (n = 231) or lobectomy (n = 1164), were categorized by their EGFR mutation status and the surgical procedures performed. The follow-up was conducted for a median of 45.3 months.

RESULTS

The 5-year overall survival (OS) rates after sublobar resections (n = 39) were comparable to those after lobectomy (n = 359) in patients with EGFR mutation-positive tumors (80.5% [95% CI, 51.3%-93.2%] vs 88.8% [95% CI, 84.1%-92.1%], respectively; P = .16). Multivariable Cox regression analysis of OS revealed that the surgical procedure was an independent prognostic predictor in the entire cohort (hazard ratio, 0.6; 95% CI, 0.4-1.0; P = .028), but it was not an independent prognostic predictor in patients with EGFR-mutated tumors (hazard ratio, 0.6; 95% CI, 0.2-1.7; P = .32).

CONCLUSIONS

Sublobar resection with a secure surgical margin could be a viable option for appropriately selected patients with peripheral early-stage NSCLC tumors measuring 2 to 4 cm and harboring EGFR mutations, because it provides comparable OS to that of lobectomy.

Effectiveness of pleurodesis for postoperative air leaks after lung resection

BACKGROUND

Pleurodesis is often performed for air leaks; however, the ideal materials and timing of the procedure remain controversial. We investigated the efficacy of pleurodesis using different materials and timing.

METHODS

We retrospectively reviewed 913 consecutive patients who underwent segmentectomy or lobectomy for non-small cell lung cancer between 2014 and 2021. Pleurodesis efficacy was assessed on the day of chest tube removal.

RESULTS

Eighty-six patients (9%) underwent pleurodesis for postoperative air leaks. Pleurodesis was performed on a median of postoperative day (POD) 5. Talc was the most frequently used material (n = 52, 60%), followed by autologous blood patches (n = 20, 23%), OK-432 (n = 12, 14%), and others (n = 2, 2%). No difference existed in the number of days from initial pleurodesis to chest tube removal among the three groups (talc, 3 days; autologous blood patch, 3 days; OK-432, 2 days; P = 0.55). No difference in patient background, except for sex, was observed between patients who underwent pleurodesis within 4 PODs and those who underwent pleurodesis on POD 5 or later. Drainage time was significantly shorter in patients who underwent pleurodesis within 4 PODs (median, 7 vs. 9 days; P = 0.004).

CONCLUSIONS

The efficacies of autologous blood patch, talc, and OK-432 would be considered comparable and early postoperative pleurodesis could shorten drainage time. Prospective studies are required.

A multicenter propensity score-matched analysis of lymphadenectomy in N1-positve lung cancer

OBJECTIVES

Selective mediastinal lymph node dissection based on lobe-specific metastases is widely recognized in daily practice. However, the significance of mediastinal lymph node dissection for N1-positive tumors has not been elucidated.

METHODS

We retrospectively reviewed 359 patients with N1-positive lung cancer who underwent lobectomy with systematic mediastinal lymph node dissection (systematic lymph node dissection) (n = 150) and lobe-specific mediastinal lymph node dissection (lobe-specific lymph node dissection) (n = 209). The operative and postoperative results and their propensity score-matched pairs were compared. The factors affecting survival were assessed using competing risk and multivariable analyses.

RESULTS

The cumulative incidence of recurrence and the cumulative incidence of cancer-specific death were not significantly different between systematic and lobe-specific lymph node dissection in entire cohort. In the propensity score-matched cohort (83 pairs), systematic lymph node dissection tended to detect N2 lymph node metastasis more frequently (55.4 vs. 41%, P = 0.087). Eleven patients (13.2%) in the systematic lymph node dissection group had a metastatic N2 lymph node 'in the systematic lymph node dissection field' that lobe-specific lymph node dissection did not dissect. The oncological outcomes between patients undergoing systematic lymph node dissection (5-year cumulative incidence of recurrence, 62.1%; 5-year cumulative incidence of cancer-specific death, 27.9%) and lobe-specific lymph node dissection (5-year cumulative incidence of recurrence, 60.1%; 5-year cumulative incidence of cancer-specific death, 23.3%) were similar. The propensity score-adjusted multivariable analysis for cumulative incidence of recurrence revealed that the prognosis associated with systematic lymph node dissection was comparable with the prognosis with lobe-specific lymph node dissection (hazard ratio, 1.17; 95% confidence interval, 0.82-1.67; P = 0.37).

CONCLUSIONS

The extent of lymph node dissection can affect accurate pathological staging; however, it was not associated with survival outcome in the treatment of N1-positive lung cancer.

Risk factors for loss of pulmonary function after wedge resection for peripheral ground-glass opacity dominant lung cancer

OBJECTIVES

This study aimed to identify the risk factors for pulmonary functional deterioration after wedge resection for early-stage lung cancer with ground-glass opacity, which remain unclear, particularly in low-risk patients.

METHODS

We analysed 237 patients who underwent wedge resection for peripheral early-stage lung cancer in JCOG0804/WJOG4507L, a phase III, single-arm confirmatory trial. The changes in forced expiratory volume in 1 s were calculated pre- and postoperatively, and a cutoff value of -10%, the previously reported reduction rate after lobectomy, was used to divide the patients into 2 groups: the severely reduced group (≤-10%) and normal group (>-10%). These groups were compared to identify predictors for severe reduction.

RESULTS

Thirty-seven (16%) patients experienced severe reduction. Lesions with a total tumour size ≥1 cm were significantly more frequent in the severely reduced group than in the normal group (89.2% vs 71.5%; P = 0.024). A total tumour size of ≥1 cm [odds ratio (OR), 3.287; 95% confidence interval (CI), 1.114-9.699: P = 0.031] and pleural indentation (OR, 2.474; 95% CI, 1.039-5.890: P = 0.041) were significant predictive factors in the univariable analysis. In the multivariable analysis, pleural indentation (OR, 2.667; 95% CI, 1.082-6.574; P = 0.033) was an independent predictive factor, whereas smoking status and total tumour size were marginally significant.

CONCLUSIONS

Of the low-risk patients who underwent pulmonary wedge resection for early-stage lung cancer, 16% experienced severe reduction in pulmonary function. Pleural indentation may be a risk factor for severely reduced pulmonary function in pulmonary wedge resection.

Hypoxia-inducible factor 1α modulates interstitial pneumonia-mediated lung cancer progression

BACKGROUND

The prognosis of patients with lung cancer accompanied by interstitial pneumonia is poorer than that of patients with lung cancer but without interstitial pneumonia. Moreover, the available therapeutic interventions for lung cancer patients with interstitial pneumonia are limited. Therefore, a new treatment strategy for these patients is required. The aim of the present study was to investigate the pathophysiological relationship between interstitial pneumonia and lung cancer and explore potential therapeutic agents.

METHODS

A novel hybrid murine model of lung cancer with interstitial pneumonia was established via bleomycin-induced pulmonary fibrosis followed by orthotopic lung cancer cell transplantation into the lungs. Changes in tumor progression, lung fibrosis, RNA expression, cytokine levels, and tumor microenvironment in the lung cancer with interstitial pneumonia model were investigated, and therapeutic agents were examined. Additionally, clinical data and samples from patients with lung cancer accompanied by interstitial pneumonia were analyzed to explore the potential clinical significance of the findings.

RESULTS

In the lung cancer with interstitial pneumonia model, accelerated tumor growth was observed based on an altered tumor microenvironment. RNA sequencing analysis revealed upregulation of the hypoxia-inducible factor 1 signaling pathway. These findings were consistent with those obtained for human samples. Moreover, we explored whether ascorbic acid could be an alternative treatment for lung cancer with interstitial pneumonia to avoid the disadvantages of hypoxia-inducible factor 1 inhibitors. Ascorbic acid successfully downregulated the hypoxia-inducible factor 1 signaling pathway and inhibited tumor progression and lung fibrosis.

CONCLUSIONS

The hypoxia-inducible factor 1 pathway is critical in lung cancer with interstitial pneumonia and could be a therapeutic target for mitigating interstitial pneumonia-mediated lung cancer progression.

Lymph node dissection in small peripheral lung cancer: Supplemental analysis of JCOG0802/WJOG4607L

OBJECTIVE

The optimal region of lymph node dissection (LND) during segmentectomy in patients with small peripheral non-small cell lung cancer requires clarification. Through a supplemental analysis of the Japan Clinical Oncology Group (JCOG) 0802/West Japan Oncology Group (WJOG) 4607L, we investigated the associated factors, distribution, and recurrence pattern of lymph node metastases (LNMs) and proposed the optimal LND region.

METHODS

Of the 1106 patients included in the JCOG0802/WJOG4607L, 1056 patients with LNDs were included in this supplemental analysis. We investigated the distribution and recurrence pattern of LNMs along with the radiologic findings (with ground-glass opacity, part-solid tumor; without ground-grass opacity component, pure-solid tumor).

RESULTS

The radiologic findings were the only significant factor for LNMs. Of 533 patients with part-solid tumors, 8 (1.5%) had LNMs. Further, only 3 (0.5%) patients had pN2 disease, and no patients had interlobar LNMs from nonadjacent segments. Of the 523 patients with pure-solid tumors, 55 (10.5%) had LNMs, and 28 (5.4%) had pN2 disease. Five patients had metastases to nonadjacent interlobar lymph nodes (LNs). Two (2.0%) patients with S6 tumors had upper mediastinal LNMs. In addition, the incidence of mediastinal LN recurrence in patients with S6 lung cancer was greater in those who underwent selective LND than those who underwent systematic LND (P = .0455).

CONCLUSIONS

Nonadjacent interlobar and mediastinal LND have little impact on pathologic nodal staging in patients with part-solid tumors. In contrast, selective LND is recommended at least for patients with pure-solid tumors.

Asian Perspective on Lung Cancer Screening

Lung cancer is the leading cause of cancer-related mortality in Japan and worldwide. Early detection of lung cancer is an important strategy for decreasing mortality. Advances in diagnostic imaging have made it possible to detect lung cancer at an early stage in medical practice. Conversely, screening of asymptomatic healthy populations is recommended only when the evidence shows the benefits of regular intervention. Due to a variety of evidence and racial differences, screening methods vary from country to country. This article focused on the perspective of lung cancer screening in Japan.

Segmentectomy for cancer control in radiologically pure-solid clinical stage IA3 lung cancer

OBJECTIVES

This study aimed to compare cancer control after segmentectomy and lobectomy in patients with radiologically pure-solid clinical stage IA3 non-small-cell lung cancer (NSCLC).

METHODS

Patients with radiologically pure-solid clinical stage IA3 NSCLC who underwent lobectomy or segmentectomy at 3 institutions between 2010 and 2019 were identified. We estimated propensity scores to adjust for confounding variables regarding tumour malignancy, including age, sex, smoking history, tumour size, maximum standardized uptake value on 18F-fluorodeoxyglucose positron emission tomography, lymph node dissection, histological type and lymphatic, vascular and pleural invasion. Cumulative incidence of recurrence (CIR) was evaluated as a primary end point.

RESULTS

Among 412 patients, postoperative recurrence occurred in 7 of 44 patients (15.9%) undergoing segmentectomy, and 71 of 368 patients (19.3%) undergoing lobectomy. CIR was comparable between patients undergoing segmentectomy (5-year rate, 21.9%) and those undergoing lobectomy (5-year rate, 20.8%; P = 0.88). Locoregional recurrence did not differ between patients undergoing segmentectomy (6.8%) and those undergoing lobectomy (9.0%). In multivariable analysis, segmentectomy (versus lobectomy) was not identified as an independent prognostic factor for CIR (hazard ratio, 1.045; 95% confidence interval, 0.475-2.298; P = 0.91). In propensity score matching of 40 pairs, CIR was not significantly different between patients undergoing segmentectomy (5-year rate, 20.7%) and those undergoing lobectomy (5-year rate, 18.4%; P = 0.81).

CONCLUSIONS

Cancer control may be comparable between segmentectomy and lobectomy in patients with radiologically pure-solid clinical stage IA3 NSCLC. Further studies are warranted to clarify the survival benefits of segmentectomy in these patients.

Sublobar Resection for Non-Small Cell Lung Cancer in Octogenarians: A Prospective, Multicenter Study

BACKGROUND

Segmentectomy is a good surgical option for peripheral, early, non-small cell lung cancer (NSCLC) ≤2 cm. However, the role of sublobar resection including wedge resection and segmentectomy remains unclear for octogenarians with >2-cm but ≤4-cm early-stage NSCLC, for which lobectomy is a standard treatment.

METHODS

By use of a prospective registry, 892 patients aged ≥80 years with operable lung cancer were enrolled at 82 institutions. Of these, we analyzed the clinicopathologic findings and surgical outcomes of 419 patients with NSCLC tumors of 2 to 4 cm during a median follow-up of 50.9 months between April 2015 and December 2016.

RESULTS

Five-year overall survival (OS) was slightly but not significantly worse after sublobar resection than after lobectomy in the entire cohort (54.7% [95% CI, 43.2%-93.0%] vs 66.8% [95% CI, 60.8%-72.1%]; P = .09). Multivariable Cox regression analysis of OS revealed that these surgical procedures were not independent prognostic predictors (hazard ratio, 0.8 [0.5-1.1]; P = .16). The 5-year OS was comparable between 192 patients who could tolerate lobectomy but were treated by sublobar resection or lobectomy (67.5% [95% CI, 48.8%-80.6%] vs 71.5% [95% CI, 62.9%-78.4%]; P = .79). Recurrence after sublobar resection and lobectomy was locoregional in 11 (11%) of 97 and in 23 (7%) of 322 patients, respectively.

CONCLUSIONS

OS might be equivalent between sublobar resection with a secure surgical margin and lobectomy for selected patients aged ≥80 years with peripheral early-stage NSCLC tumors of 2 to 4 cm who can tolerate lobectomy.

Extracellular vesicle-associated microRNA signatures related to lymphovascular invasion in early-stage lung adenocarcinoma

Lymphovascular invasion (LVI) is a fundamental step toward the spread of cancer. Extracellular vesicles (EVs) promote cellular communication by shuttling cargo, such as microRNAs (miRNAs). However, whether EV-associated miRNAs serve as biomarkers for LVI remains unclear. This study aimed to identify EV-associated miRNAs related to LVI and validate the miRNA levels from patients with early-stage lung adenocarcinoma (LADC). Blood samples were collected from patients undergoing pulmonary resection for stage I LADC before surgery. The patients were classified into three groups according to the presence of LVI and postoperative recurrence. Serum-derived EVs in the derivation cohort were used for small RNA sequencing, while the selected LVI miRNA candidates were validated via real-time quantitative polymerase chain reaction using 44 patient and 16 healthy donor samples as the validation cohorts. Five miRNAs (miR-99b-3p, miR-26a-5p, miR-93-5p, miR-30d-5p, and miR-365b-3p) were assessed, and miR-30d-5p (p = 0.036) levels were significantly downregulated in the LVI-positive group. miR-30d-5p levels in healthy donors were lower than those in LADC patients. Patients with high miR-30d-5p levels had favorable survival compared to those with low miR-30d-5p levels. miR-30d-5p level in EVs may serve as a promising biomarker for detecting LVI in patients with early-stage LADC.

Segmentectomy for ground-glass-dominant lung cancer with a tumour diameter of 3 cm or less including ground-glass opacity (JCOG1211): a multicentre, single-arm, confirmatory, phase 3 trial

BACKGROUND

Although segmentectomy is a widely used surgical procedure, lobectomy is the standard procedure for resectable non-small-cell lung cancer (NSCLC). This study aimed to evaluate the efficacy and safety of segmentectomy for NSCLC up to 3 cm in size, including ground-glass opacity (GGO) and predominant GGO.

METHODS

A multicentre, single-arm, confirmatory phase 3 trial was conducted across 42 institutions (hospitals, university hospitals, and cancer centres) in Japan. Segmentectomy with hilar, interlobar, and intrapulmonary lymph node dissection was performed as protocol surgery for patients with a tumour diameter of up to 3 cm, including GGO and dominant GGO. Eligible patients were those aged 20-79 years with an Eastern Cooperative Oncology Group performance score of 0 or 1 and clinical stage IA tumour confirmed by thin-sliced CT. The primary endpoint was 5-year relapse-free survival (RFS). This study is registered with the University Hospital Medical Information Network Clinical Trials (UMIN000011819), and is ongoing.

FINDINGS

A total of 396 patients were registered from Sept 20, 2013, to Nov 13, 2015, of whom 357 underwent segmentectomy. At a median follow-up of 5·4 years (IQR 5·0-6·0), the 5-year RFS was 98·0% (95% CI 95·9-99·1). This finding exceeded the 87% of the pre-set threshold 5-year RFS and the primary endpoint was met. Grade 3 or 4 early postoperative complications occurred in seven patients (2%), but no grade 5 treatment-related deaths occurred.

INTERPRETATION

Segmentectomy should be considered as part of standard treatment for patients with predominantly GGO NSCLC with a tumour size of 3 cm or less in diameter, including GGO even if it exceeds 2 cm.

FUNDING

National Cancer Centre Research and Development Fund and Japan Agency for Medical Research and Development.

Complications and Survival After Lung Cancer Resection in Interstitial Lung Disease

BACKGROUND

Idiopathic pulmonary fibrosis guidelines changed the high-resolution computed tomography (HRCT) pattern from 3 to 4 categories in 2018. We assessed the relationship between surgical outcomes and HRCT patterns according to the 2018 guidelines.

METHODS

Among 1503 patients who underwent pulmonary resection for clinical stage Ⅰ to stage Ⅲ lung cancer at our institution between April 2007 and June 2019, we retrospectively investigated 218 with interstitial lung abnormalities based on preoperative HRCT. We reclassified all interstitial lung abnormality cases with preoperative HRCT from 3 patterns-usual interstitial pneumonia (UIP), possible, and inconsistent with UIP-of the previous (2011) guidelines to 4 patterns-UIP, probable UIP, indeterminate, and alternative diagnosis-according to the new consensus guideline of idiopathic pulmonary fibrosis (2018). The occurrence of acute exacerbations and survival were analyzed, and the association with HRCT pattern was investigated.

RESULTS

Interstitial lung abnormality cases were reclassified as UIP (n = 55 [25.2%]), probable UIP (n = 36 [16.5%]), indeterminate UIP (n = 56 [25.7%]), and alternative diagnosis (n = 71 [32.6%]). Acute exacerbations developed in 21 patients (UIP pattern, n = 9 [16.4%]; probable UIP, n = 5 [13.9%]; indeterminate, n = 3 [5.4%]; and alternative diagnosis, n = 4 [5.6%]). Multivariable Cox regression revealed that UIP pattern or probable UIP pattern of the 2018 guideline was an independent risk factor for severe acute exacerbations (grade III-Ⅴ; odds ratio, 6.81; 95% CI, 1.42-32.60) and postoperative overall survival (hazard ratio, 3.12; 95% CI, 1.70-5.73).

CONCLUSIONS

UIP and probable UIP patterns were risk factors for postoperative severe acute exacerbations and death. The HRCT patterns of the 2018 guidelines can stratify outcomes of lung resection.

Feasibility of repeated ipsilateral anatomical pulmonary resection

PURPOSE

This study aimed to elucidate the feasibility of repeated ipsilateral anatomical pulmonary resection.

METHODS

The subjects of this retrospective analysis were 50 patients who underwent ipsilateral anatomical pulmonary resection after major lung surgery. The patients were divided into two groups according to the type of primary operation performed: a repeated anatomical pulmonary resection group (RA group; n = 24) and an anatomical pulmonary resection after wedge resection group (AW group; n = 26). We compared the perioperative outcomes of the two groups.

RESULTS

Completion lobectomy was performed in 9 of the 24 patients (38%) from the RA group and adhesion of the pulmonary hilum was more severe in this group (P = 0.004). Although the operative time was significantly longer in the RA group (P = 0.030), there was no significant difference in the amount of blood loss (P = 0.217) between the groups. A significantly higher rate of severe postoperative complications was observed in the RA group (42%) than in the AW group (12%) (P = 0.024). None of the patients who underwent repeated surgery died within 90 days postoperatively.

CONCLUSION

Although repeated anatomical pulmonary resection is a more challenging procedure than anatomical resection after wedge resection, it does not increase short-term mortality; therefore, it is a feasible treatment option.

Tumour location predicts occult N1 nodal metastasis in clinical stage I non-small-cell lung cancer

OBJECTIVES

Pathological lymph node metastases are often observed in patients with clinical N0 lung cancer. Identifying preoperative predictors of occult hilar nodal metastasis (OHNM) is important in determining the surgical procedure in patients with clinical stage I non-small-cell lung cancer. This study aimed to determine the frequency and predictors of OHNM by tumour location in these patients.

METHODS

Between April 2007 and May 2019, data of patients who underwent lobectomy or segmentectomy for clinical stage I pure-solid non-small-cell lung cancer were retrospectively reviewed. The ratio of the distance from the pulmonary hilum to the proximal side of the tumour to the distance from the pulmonary hilum to the visceral pleural surface through the centre of the tumour, named 'distance ratio (DR)', was calculated. The relationship of the DR with clinicopathological findings and prognosis was discussed.

RESULTS

A total of 357 patients were enrolled. OHNM frequency was 14.6%. Patients were divided into 2 groups based on whether the DR was ≤0.67 (central type) or >0.67 (peripheral type). The frequency of OHNM was significantly higher in the DR ≤0.67 group (21.5% vs 7.4%; P < 0.001). Multivariable analysis revealed that DR was the only independent preoperative predictor of OHNM (odds ratio, 3.63; 95% confidence interval, 1.83-7.18; P < 0.001).

CONCLUSIONS

The frequency of OHNM was significantly lower in peripheral-type lung cancer; therefore, tumour location was the most important preoperative predictor of OHNM.

Segmentectomy preserves better immune-nutritional status than lobectomy in patients with early-stage lung cancer

OBJECTIVES

This study aimed to compare the postoperative immune-nutritional status of patients undergoing segmentectomy and lobectomy for early-stage non-small-cell lung cancer.

METHODS

Patients with clinical stage 0-IA non-small-cell lung cancer who underwent lobectomy or segmentectomy were retrospectively analysed. Postoperative immune-nutritional indices (prognostic nutritional index, serum albumin levels and total lymphocyte count) at 1 month, 6 months, 1 year, 2 years and 3 years after surgery were compared using mixed effects linear models and mixed effects logistic regression models.

RESULTS

There were 164 and 210 patients in the lobectomy and segmentectomy groups, respectively. Postoperative prognostic nutritional index and albumin levels were significantly higher in the segmentectomy group than those in the lobectomy group (P < 0.001 and P < 0.001, respectively), despite the nonsignificant difference in the total lymphocyte count (P = 0.563). In 126 propensity score-matched pairs adjusted for confounding variables affecting postoperative nutritional status, postoperative prognostic nutritional index and albumin levels were significantly higher in the segmentectomy group than in the lobectomy group (P = 0.009 and P = 0.007, respectively). At each time point after surgery, these indices were higher in the segmentectomy group than in the lobectomy group at 1 month, 2 years and 3 years postoperatively. There were significantly more patients with lower immune-nutritional indices (prognostic nutritional index <45, albumin <4.0 g/dl) in the lobectomy group than in the segmentectomy group at 3 years postoperatively (P = 0.026 and P = 0.029, respectively), despite nonsignificant statistical differences throughout the study period (P = 0.219 and P = 0.113, respectively).

CONCLUSIONS

Patients who underwent segmentectomy showed better postoperative immune-nutritional status than those who underwent lobectomy.

Wedge resection is an acceptable treatment option for radiologically low-grade lung cancer with solid predominance

OBJECTIVES

This study aimed to determine the clinical characteristics for predicting low-grade cancer in radiologically solid predominant non-small-cell lung cancer (NSCLC) and compare the survival outcomes of wedge resection with those of anatomical resection for patients with and without these characteristics.

METHODS

Consecutive patients with clinical stages IA1-IA2 NSCLC showing radiologically solid predominance ≤2 cm at 3 institutions were retrospectively evaluated. Low-grade cancer was defined as the absence of nodal involvement and blood vessel, lymphatic and pleural invasion. The predictive criteria for low-grade cancer were established by multivariable analysis. The prognosis of wedge resection was compared with that of anatomical resection for patients who met the criteria, using the propensity score-matched analysis.

RESULTS

Among 669 patients, multivariable analysis showed that ground-glass opacity (GGO) (P < 0.001) on thin-section computed tomography and an increased maximum standardized uptake value on 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography (P < 0.001) were independent predictors of low-grade cancer. The predictive criteria were defined as GGO presence and maximum standardized uptake value ≤1.1 (specificity: 97.8%, sensitivity: 21.4%). In the propensity score-matched pairs (n = 189), overall survival (P = 0.41) and relapse-free survival (P = 0.18) were not significantly different between patients who underwent wedge resection and anatomical resection among those who fulfilled the criteria.

CONCLUSIONS

The radiologic criteria for GGO and a low maximum standardized uptake value could predict low-grade cancer, even in solid-dominant NSCLC sized ≤2 cm. Wedge resection could be an acceptable surgical option for patients with radiologically predicted indolent NSCLC showing a solid-dominant appearance.

[Dawn of Radical Segmentectomy for Small Sized Peripheral Non-small Cell Lung Cancer]

The result of prospective, randomized, controlled, trial, Japan Clinical Oncology Group (JCOG) 0802/ West Japan Oncology Group( WJOG) 4607L, has been published in April 2022. The superiority in overall survival for patients who underwent segmentectomy for small sized peripheral non-small cell lung cancer( NSCLC)( whole tumor size≤2 cm, C/T ratio>0.5) compared with those undergoing lobectomy has been demonstrated for the first time in the world. Segmentectomy might become a standard surgical procedure for such tumors. Consequently, the opportunity to perform segmentectomy will increase. Developing techniques for segmentectomy is an urgent issue for general thoracic surgeons because segmentectomy generally requires more advanced surgical technique than lobectomy. In particular, the radical segmentectomy is an anatomically limited resection with hilar and mediastinal lymph node dissection. That means anatomically accurate resection of the pulmonary segment. There are a lot of points to be mastered in operative indications based on tumor size, phenotype, and location, understandings of anatomy, surgical techniques, transition to lobectomy, and so on. In this article, we would like to share some tips on segmentectomy primarily focusing on the surgical techniques.

Usefulness of serum S100A4 and positron-emission tomography on lung cancer accompanied by interstitial pneumonia

BACKGROUND

The S100 calcium-binding protein A4 (S100A4) and the accumulation of [18F]-fluoro-2-deoxy-D-glucose (FDG) in noncancerous interstitial pneumonia (IP) area are predictors of postoperative acute exacerbation (AE) of IP after pulmonary resection for lung cancer with IP. However, the significance of combining these markers for predicting short-term outcome and long-term prognosis is not known.

METHODS

Patients diagnosed with IP on preoperative high-resolution computed tomography and who had undergone pulmonary resection for primary lung cancer between April 2010 and March 2019 at Hiroshima University were included in this study. Predictive factors for the cumulative incidence of death from other than lung cancer (CIDOL) were investigated using the Fine and Gray model. CIDOL, perioperative outcome, and cumulative incidence of all death (CIAD) were retrospectively compared based on serum S100A4 and FDG accumulation.

RESULTS

A total of 121 patients were included in this study. High S100A4 (hazard ratio [HR], 2.541; p = 0.006) and FDG accumulation (HR, 3.199; p = 0.038) were significant predictors of CIDOL. AE of IP occurred only in patients with high S100A4/FDG (+). CIDOL of patients with high S100A4/FDG (+) was higher than those with high S100A4/FDG (-) or low S100A4/FDG (+) (p < 0.001), and CIAD of patients with high S100A4/FDG (+) was also higher than those with high S100A4/FDG (-) or low S100A4/FDG (+) patients (p = 0.021).

CONCLUSIONS

Serum S100A4 and FDG accumulation in the noncancerous IP area were significant predictors of CIDOL after lung resection for lung cancer with IP and may help decide the treatment strategy.

Discrepancy Between Radiological and Pathological Tumor Size in Early-Stage Non-Small Cell Lung Cancer: A Multicenter Study

Discrepancies between radiological whole tumor size (RTS) and pathological whole tumor size (PTS) are sometimes observed. Unexpected pathological upsize may lead to insufficient margins during procedures like sub lobar resections. Therefore, this study aimed to investigate the current status of these discrepancies and identify factors resulting in pathological upsize in patients with early-stage non-small cell lung cancer (NSCLC). Data from a multicenter database of 3092 patients with clinical stage 0-IA NSCLC who underwent pulmonary resection were retrospectively analyzed. Differences between the RTS and PTS were evaluated using Pearson's correlation analysis and Bland-Altman plots. Unexpected pathological upsize was defined as an upsize of ≥1 cm when compared to the RTS, and the predictive factors of this upsize were identified based on multivariable analyses. The RTS and PTS showed a positive linear relationship (r = 0.659), and the RTS slightly overestimated the PTS. The Bland-Altman plot showed 131 of 3092 (5.2%) cases were over the upper 95% limits of agreement. In multivariable analyses, a maximum standardized uptake value (SUVmax) of the primary tumor on 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography (odds ratio [OR], 1.070; 95% confidence interval [CI], 1.035-1.107; P < 0.001) and the adenocarcinoma histology (OR, 1.899; 95% CI, 1.071-3.369; P =0.049) were independent predictors of unexpected pathological upsize. More of the adenocarcinomas with pathological upsize were moderately or poorly differentiated, when compared to those without. The RTS tends to overestimate the PTS; however, care needs to be taken regarding unexpected pathological upsize, especially in adenocarcinomas with a high SUVmax.

Impact of the amount of preoperative erector spinae muscle in stage I non-small-cell lung cancer

OBJECTIVES

Erector spinae muscle (ESM) is an antigravity muscle group that can be evaluated as an index of muscle loss on chest computed tomography. The amount of ESM has been reported to be related to the prognosis of several respiratory diseases. However, few studies clarify the impact on postoperative non-small-cell lung cancer (NSCLC). We investigated the relationship between ESM and postoperative prognosis in patients with early-stage NSCLC.

METHODS

We reviewed the medical records of 534 patients with stage I NSCLC who underwent lobectomy or segmentectomy. The ESM was identified by preoperative computed tomography, and the amount was normalized according to height and sex. Overall survival, lung cancer-related deaths and non-lung cancer-related deaths (NLCRD) were analysed using log-rank and Gray's tests. Multivariable analyses were conducted to identify factors that influenced overall survival (OS) and NLCRD.

RESULTS

The amount of ESM normalized according to height and sex was significantly associated with age and body mass index. When the amount was low, OS (5-year OS, 79.6 vs 89.5%; P< 0.001) and NLCRD (5-year cumulative mortality rate, 14.7 vs 6.8%; P< 0.001) were significantly worse, although no difference was found in lung cancer-related deaths.

CONCLUSIONS

The amount of preoperative ESM was strongly related to non-lung cancer-related death and was a significant prognostic factor for stage I NSCLC. Patients with a low amount of the muscle should be treated based on proper risk assessment.

Segmentectomy for clinically early-stage primary squamous cell carcinoma of the lung

BACKGROUND

Squamous cell carcinoma of the lung-the second most common subtype of lung cancer-has a poorer prognosis than lung adenocarcinoma. However, in contrast to lobectomy, the oncological outcomes after segmentectomy for primary squamous cell carcinomas remain unknown; hence, this study investigated these outcomes.

METHODS

Patients who underwent lobectomy or segmentectomy for clinically node-negative primary lung squamous cell carcinoma with a whole tumor size of ≤ 30 mm on preoperative computed tomography scan during April 2010 to December 2020 were included in this study. The cumulative incidence of recurrence (CIR) among all included patients and propensity score-matched patients were compared using the Gray method. Multivariate analysis using propensity scores and surgical procedures was performed using the Fine and Gray method.

RESULTS

Overall, 230 patients were included in this study; of these, 172 (74.8%) underwent lobectomy and 58 (25.2%) underwent segmentectomy. No significant differences were observed in the CIR between patients who underwent lobectomy and those who underwent segmentectomy (5-year rate 18.1% vs. 14.2%; p  =  0.787). Moreover, no significant differences in CIR were observed between the propensity score-matched patients who underwent lobectomy (n = 43) and those who underwent segmentectomy (n   =  43) (8.6% vs. 8.0%; p = 0.571). Multivariable analysis was performed for CIR using the propensity score; it revealed that segmentectomy was not a significant predictor of worse CIR (hazard ratio, 0.987; p =   0.980).

CONCLUSIONS

Segmentectomy may be feasible for treating clinically early-stage lung squamous cell carcinoma; its oncological outcomes are similar to those of lobectomy.

The intersegmental pulmonary vein is not always located on the intersegmental plane of the lung: Evaluation with 3-dimensional volume-rendering image reconstruction

Objective

To clarify whether intersegmental pulmonary veins are always located on the intersegmental plane and determine the division from which blood flows into them.

Methods

We analyzed representative intersegmental veins located between the upper/lingular and superior/basal division of the lungs using preoperative chest computed tomography (CT) DICOM data from 22 patients who underwent lobectomy or segmentectomy during 2020. The location and blood flow of V³a+b and V⁶b+c were assessed using REVORAS (Ziosoft), a novel volume-rendering 3-dimensional (3D) image reconstruction software dedicated to lung segmentectomy.

Results

The V³a+b was in the upper division and on the intersegmental plane between the upper and lingular divisions of the left lung in 11 patients (50%) each. A main root of V³a+b was not found in the lingular division, but some peripheral flow in the V³a+b was derived from it in 14 patients (64%). The V⁶b+c was found in the superior division of the right lower lobe in 13 patients (59%) and the left lower lobe in 10 patients (45%), and on the intersegmental plane between the superior and basal division of the right lower lobe in 6 patients (27%) and the left lower lobe in 10 patients (45%). A main root of V⁶b+c was imperceptible in the basal division. Some peripheral blood flow was derived from the basal division in 6 patients (27%) with V⁶b+c veins located in the right lower lobe and in 8 patients (36%) with V⁶b+c veins located in the left lower lobe.

Conclusions

Precise evaluation of intersegmental veins using preoperative volume-rendering 3D reconstructed CT images provides useful anatomic information for separating intersegmental pulmonary parenchyma.

Possible Therapeutic Utility of anti-Cell Adhesion Molecule 1 Antibodies for Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive malignant tumor, and the effective therapeutic drugs are limited. Thus, the establishment of novel therapeutic method is desired. Considerable proportion of MPMs are shown to express cell adhesion molecule 1 (CADM1), and to use CADM1 to bind to and proliferate on the pleural mesothelial surface, suggesting that CADM1 is a possible therapeutic target. Here, anti-CADM1 ectodomain chicken monoclonal antibodies, 3E1 and 9D2, were examined for their possible therapeutic utility. The full-length form of CADM1 was expressed in eight out of twelve human MPM cell lines. MPM cell lines were cultured on a confluent monolayer of mesothelial MeT-5A cells in the presence of 9D2, the neutralizing antibody. 9D2 suppressed the cell growth of CADM1-positive MPM cells with the loss and aggregation of CADM1 molecules on the MPM cell membrane, but not of CADM1-negative MPM cells. Co-addition of 3E1, lacking the neutralizing action, enhanced the growth-suppressive effect of 9D2. The two antibodies were tested as drug delivery vectors. 3E1 was converted into a humanized antibody (h3E1) and conjugated with monomethyl auristatin E (MMAE), a tubulin polymerization inhibitor. When the resulting h3E1–MMAE antibody-drug conjugate (ADC) was added to the standard cultures of CADM1-positive MPM cells, it suppressed the cell growth in a dose-dependent manner. Co-addition of 9D2 enhanced the growth-suppressive effect of h3E1–MMAE ADC. Anti-CADM1 ectodomain antibodies were suggested to serve as both antibody drugs and drug vectors in the treatment of MPM.

Psychological states regarding adjuvant chemotherapy in patients with non-small cell lung cancer

BACKGROUND

Understanding the anxieties and emotions of patients with lung cancer before and after radical surgery is crucial in the decision to undergo postoperative adjuvant chemotherapy. However, the psychological states and changes associated with adjuvant chemotherapy during perioperative periods in patients with non-small cell lung cancer (NSCLC) remain unclear.

PATIENTS AND METHODS

Participants with a self-reported diagnosis of pathological stage II or III NSCLC who underwent complete surgical resection and received information on postoperative adjuvant chemotherapy (n = 101) were sampled from an online panel in Japan from October 9 to November 19, 2020. Eligible and consenting participants completed a self-administered online questionnaire survey about their disease, and their psychological states were assessed.

RESULTS

The majority of patients (39, 38.6%) were 60-69 years of age, and 87 (86.1%) were men. A total of 59 (58.4%) and 42 (41.6%) patients had pathological stages II and III, respectively. Regardless of the situation, more than 75% of the patients were anxious about the possibility of recurrence after complete surgical resection for lung cancer. Approximately 70% of respondents selected the option of "I will get adjuvant chemotherapy" on any precondition. Among them, almost all respondents selected the option "want to do everything I can do now to prevent recurrence."

CONCLUSION

In this small sample of respondents with NSCLC from Japan, it is important for surgeons and physicians to explain the condition and corresponding therapy for lung cancer, while considering the possibility of recurrence in any situation, even before surgery as a curative intent.

Segmentectomy versus wedge resection for radiological solid predominant and low metabolic non-small cell lung cancer

OBJECTIVES

The prognosis of segmentectomy and wedge resection for solid predominant early-stage non-small cell lung cancer with low metabolic activity is unclear.

METHODS

This study aimed to assess patients who underwent segmentectomy or wedge resection with curative intent for clinically node-negative non-small cell lung cancer presenting as a solid predominant tumour (consolidation tumour ratio >50%) with a whole size ≤3 cm and [18F]-fluoro-2-deoxy-D-glucose accumulation weaker than that of the mediastinum tissue (Deauville score, 1 or 2) on positron emission tomography/computed tomography. The cumulative incidence of recurrence (CIR) was compared using the Gray method, and the predictive factor of CIR was analysed using the Fine and Gray method.

RESULTS

Of 140 patients included in this study, 93 (66.4%) underwent segmentectomy and 47 (33.6%) underwent wedge resection. No significant difference in the clinical stage was found between the 2 groups. The CIR was higher with wedge resection than with segmentectomy (P = 0.004). Recurrence after wedge resection was noted in 4 (8.5%) patients, 2 of whom had a recurrent site containing lung parenchyma of the preserved lobe and hilum lymph node, which would have been resected if segmentectomy had been performed. In the multivariable analysis for CIR using inverse probability of treatment weighting and the procedure, wedge resection was a significantly worse predictive factor (hazard ratio, 12.280; P = 0.025).

CONCLUSIONS

Segmentectomy rather than wedge resection should be considered for solid predominant, small-size non-small cell lung cancer even if [18F]-fluoro-2-deoxy-D-glucose accumulation is low.

Oncological outcome of segmentectomy for early-stage non-small-cell lung cancer with invasive characteristics: a multicentre study

OBJECTIVES

Segmentectomy can provide oncologically acceptable results for small-sized non-small-cell lung cancer (NSCLC). However, in cases of NSCLC with pathological invasive characteristics such as lymphatic invasion (LY), vascular invasion (V), pleural invasion (PL) and/or lymph node metastasis, the feasibility of segmentectomy is not known.

METHODS

The patients included in the study (i) underwent lobectomy or segmentectomy for NSCLC with invasive characteristics such as LY, V, PL or pathological lymph node metastasis; (ii) presented with a node-negative, solid component-predominant tumour (consolidation tumour ratio >50%) on preoperative computed tomography; (iii) had a whole-tumour size of 2 cm or less; and (iv) presented between January 2010 and December 2019 to one of the 3 institutions. Cumulative incidences of recurrence (CIRs) after segmentectomy and lobectomy were compared.

RESULTS

A total of 321 patients were included. Segmentectomy and lobectomy were performed in 80 (24.9%) and 241 (75.1%) patients, respectively. There was no significant difference in CIR between segmentectomy (5-year CIR rate, 17.2%) and lobectomy patients (5-year CIR rate, 27.8%, P = 0.135). In the propensity score-matched cohort, there was no significant difference in CIR between segmentectomy (5-year CIR rate, 19.1%) and lobectomy patients (5-year CIR rate, 19.2%; P = 0.650). In the multivariable analysis using inverse probability of treatment weighting and surgical method, segmentectomy was not a significant predictor of worse CIR (P = 0.920).

CONCLUSIONS

Segmentectomy is feasible for clinically early-stage NSCLC irrespective of the presence of LY, V, PL or lymph node metastasis.

Segmentectomy versus lobectomy for solid predominant cN0 lung cancer: analysis using visual evaluation of positron emission tomography

OBJECTIVES

Prognosis after segmentectomy for early-stage non-small cell lung cancer (NSCLC) with a high consolidation tumour ratio (CTR) and [18F]-fluoro-2-deoxy-D-glucose (FDG) accumulation on positron emission tomography/computed tomography is unclear.

METHODS

Participants of this study were 465 patients who underwent lobectomy or segmentectomy for clinical N0 NSCLC presenting solid component predominant tumour (CTR >50%) with a whole size ≤3 cm. Accumulations of FDG on positron emission tomography/computed tomography scans were scored according to the Deauville criteria, a 5-point visual evaluating method (Deauville score). The correlations between Deauville score, prognosis, and procedures were analysed.

RESULTS

Characteristics of pathological invasiveness, such as lymphatic invasion (P < 0.001), vascular invasion (P < 0.001) and pleural invasion (P < 0.001), and non-adenocarcinoma histologies (P < 0.001) were more common in patients with Deauville scores of 3-5. The cumulative incidence of recurrence (CIR) was higher in patients with Deauville scores of 3-5 (P < 0.001). The CIR after lobectomy and segmentectomy did not differ significantly among patients with Deauville scores of 1 or 2 (P = 0.598) or those with Deauville scores of 3-5 (P = 0.322). In the analysis of propensity score matched cohort, the CIR after lobectomy and segmentectomy did not differ significantly between patients with Deauville scores of 1 or 2 and Deauville scores of 3-5.

CONCLUSIONS

Segmentectomy may be feasible for NSCLC with high CTR (>50%) and accumulation of FDG. This finding should be confirmed in larger prospective studies.

Risk of death due to other causes is lower among octogenarians with non-small cell lung cancer after wedge resection than lobectomy/segmentectomy

OBJECTIVE

We aimed to determine the influences of surgical procedures on the postoperative death of octogenarians with clinical Stage IA non-small cell lung cancer excluding cT1mi.

METHODS

We compared overall survival and the cumulative incidence of death due to all and other causes among 1 130 279, and 191 consecutive patients aged ≤79 and ≥80 years after lobectomy, segmentectomy and wedge resection at three institutions. Death due to other causes was defined as death due to any cause except non-small cell lung cancer.

RESULTS

The median followup was 53 months. The 5-year overall survival rates for patients aged ≥ 80 and ≤ 79 years after lobectomy, segmentectomy and wedge resection were respectively, 78.0% (95% confidence interval, 63.8%-87.2%) versus 91.2% (95% confidence interval, 89.0%-92.9%), 68.1% (95% confidence interval, 45.2%-83.1%) versus 90.0% (95% confidence interval, 84.6%-93.5%), and 62.7% (95% confidence interval, 44.0-76.7%) versus 84.4% (95% confidence interval, 76.3%-89.9%) (P < 0.01 for all). The cumulative incidence of death due to other causes after wedge resection was similar between patients aged ≥ 80 and ≤ 79 years (P = 0.45), but significantly higher in those aged ≥ 80, than ≤ 79 years after lobectomy or segmentectomy (P = 0.00015 and 0.00091, respectively).

CONCLUSIONS

The influence of wedge resection on death due to other causes was lower than that of lobectomy or segmentectomy in patients with non-small cell lung cancer aged ≥ 80 years. Wedge resection might be a useful option for octogenarians even if they can tolerate lobectomy/segmentectomy to avoid postoperative death due to causes other than non-small cell lung cancer.

Postoperative Pulmonary Function After Complex Segmentectomy

BACKGROUND

Segmentectomy has been increasingly used for lung cancer treatment, however there are very limited data evaluating the postoperative pulmonary function of patients treated with complex segmentectomy. We evaluated the postoperative pulmonary function of patients who underwent complex segmentectomy compared with simple segmentectomy, wedge resection, and lobectomy.

METHODS

We retrospectively analyzed data from 580 patients who underwent surgical resection. The patients were divided into four groups: complex segmentectomy (n = 135), simple segmentectomy (n = 83), wedge resection (n = 89), and lobectomy (n = 273). Functional testing included forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), and predicted diffusing capacity of the lung for carbon monoxide (%DLCO) measured preoperatively and at 12 months after surgery.

RESULTS

During the postoperative course, the complex segmentectomy and simple segmentectomy groups showed a comparable course of pulmonary function. The complex segmentectomy group significantly preserved pulmonary function compared with the lobectomy group (FVC, p = 0.017; FEV₁, p = 0.010; %DLCO, p = 0.0043). A similar trend was observed even when restricted to lung diseases in the right upper lobe. On the other hand, when comparing complex segmentectomy with wedge resection, complex segmentectomy showed a trend that was more disadvantageous than wedge resection, but this difference was not significant (FVC, p = 0.19; FEV₁, p = 0.40; %DLCO, p = 0.96).

CONCLUSIONS

Complex segmentectomy showed comparable postoperative pulmonary functions as simple segmentectomy. Complex segmentectomy could preserve pulmonary function significantly compared with lobectomy and did not result in significant loss compared with wedge resection.

Prognostic role of interstitial pneumonia with or without emphysema in patients with clinical stage I lung cancer

OBJECTIVES

The prognostic role of interstitial pneumonia with emphysema in lung cancer is not fully understood. This study aimed to examine the prognostic role of the presence of emphysema in patients with clinical stage I lung cancer and interstitial pneumonia.

METHODS

The presence of interstitial pneumonia and emphysema was evaluated on preoperative high-resolution computed tomography. In total, 836 consecutive patients with clinical stage I lung cancer who underwent complete resection between April 2007 and March 2016 were retrospectively analyzed using the log-rank test and Cox proportional hazard model to examine survival differences.

RESULTS

There was a significant difference in 5-year overall survival between patients with interstitial pneumonia and emphysema (n = 65) and those without (n = 771) (62.6% vs. 86.5%; P < 0.001). However, in patients with interstitial pneumonia on high-resolution computed tomography, there was no significant difference in 5-year overall survival between patients with emphysema (n = 65) and those without emphysema (n = 50) (62.6% vs. 59.4%, P = 0.84). Multivariable backward stepwise Cox proportional hazard analysis in patients with interstitial pneumonia showed that histology, %diffusing capacity of the lungs for carbon monoxide, radiologic interstitial pneumonia pattern and surgical procedure were independent prognostic factors for overall survival, but the presence of emphysema was not.

CONCLUSIONS

The presence of emphysema was not an independent prognostic factor for overall survival in patients with clinical stage I lung cancer with interstitial pneumonia. Poor survival of patients with IP and emphysema may be due to the presence of interstitial pneumonia.

Systematic Versus Lobe-Specific Mediastinal Lymphadenectomy for Hypermetabolic Lung Cancer

BACKGROUND

The optimal extent of lymph node dissection (LND) for hypermetabolic tumors that are associated with high rates of nodal disease, recurrence, or mortality has not been elucidated.

METHODS

We reviewed 375 patients who underwent lobectomy with lymphadenectomy for clinical T2-3 N0-1 M0 hypermetabolic non-small cell lung cancer (NSCLC) [maximum standard uptake value (SUVmax) ≥ 6.60] via a multicenter database. Extent of LND was classified into systematic mediastinal LND (systematic LND) and lobe-specific mediastinal LND (lobe-specific LND). Postoperative outcomes after lobectomy with systematic LND (n = 128) and lobe-specific LND (n = 247) were analyzed for all patients and their propensity-score-matched pairs.

RESULTS

Cancer-specific survival (CSS) and recurrence-free interval (RFI) of the systematic LND group were not significantly different from those of the lobe-specific LND group in the nonadjusted whole cohort. In the propensity-score-matched cohort (101 pairs), systematic LND dissected significantly more lymph nodes (20.0 versus 16.0 nodes, P = 0.0057) and detected lymph node metastasis more frequently (53.5% vs. 33.7%, P = 0.0069). Six (5.9%) patients in the systematic LND group had a metastatic N2 lymph node "in the systematic LND field" that lobe-specific LND could not dissect. The systematic LND group tended to have better prognosis than the lobe-specific LND group (5-year CSS rates, 82.6% versus 69.6%; 5-year RFI rates, 56.6% vs. 47.3%).

CONCLUSIONS

Systematic LND was found to harvest more metastatic lymph nodes and provide better oncological outcome than lobe-specific LND in a cohort of hypermetabolic NSCLC patients.

Complex segmentectomy in the treatment of stage IA non-small-cell lung cancer

OBJECTIVES

Although segmentectomy for lung cancer has been widely accepted, complex segmentectomy, which creates several, intricate intersegmental planes, remains controversial. Potential arguments include risk of incurability and 'failure of cancer control'. We compared the outcomes of complex segmentectomy versus lobectomy and evaluated its use in lung cancer treatment.

METHODS

We retrospectively reviewed clinical stage IA lung cancer patients who underwent complex segmentectomy (n = 99) or location-adjusted lobectomy (n = 94) between April 2009 and December 2017. Clinicopathological and postoperative results were compared. Factors affecting survival were assessed by the Kaplan-Meier method and the Cox regression analysis.

RESULTS

No significant differences were detected in 30-day mortality (0% vs 0%), overall complications (26.3% vs 21.3%) and prolonged air leakage (11.1% vs 9.6%) rates between the 2 groups, respectively. Comparable results were obtained for 5-year overall (93.5% vs 96.4%, respectively; P = 0.21) or recurrence-free (92.3% vs 88.5%, respectively; P = 0.82) survivals after complex segmentectomy or lobectomy. There were 2 (2.0%) recurrences after complex segmentectomy and 7 (7.5%) after lobectomy (P = 0.094), with 0 (0%) margin relapses in each group. Multivariable Cox regression analysis revealed that complex segmentectomy and lobectomy had a numerically similar impact on recurrence-free survival (hazard ratio 0.93, 95% confidence interval 0.32-2.69; P = 0.90).

CONCLUSIONS

Complex segmentectomy can provide acceptable short- and long-term outcomes in lung cancer treatment.

Prognosis of segmentectomy and lobectomy for radiologically aggressive small-sized lung cancer

OBJECTIVES

The purpose of this study was to determine the radiological characteristics of aggressive small-sized lung cancer and to compare the outcomes between segmentectomy and lobectomy in patients with these lung cancers.

METHODS

A series of 1046 patients with clinical stage IA1-IA2 lung cancer who underwent lobectomy or segmentectomy at 3 institutions was retrospectively evaluated to identify radiologically aggressive small-sized (solid tumour size ≤ 2 cm) lung cancers. Prognosis of segmentectomy was compared with that of lobectomy in 522 patients with radiologically aggressive small-sized lung cancer using propensity score matching.

RESULTS

Multivariable analysis showed that increasing consolidation-to-tumour ratio on preoperative high-resolution computed tomography (CT) (P = 0.037) and maximum standardized uptake on 18 fluoro-2-deoxyglucose positron emission tomography/CT (P = 0.029) was independently associated with worse recurrence-free survival. Based on analysis of the receiver operating characteristic curve, radiologically aggressive lung cancer was defined as a radiologically solid (consolidation-to-tumour ratio ≥ 0.8) or highly metabolic (maximum standardized uptake ≥ 2.5) tumour. Among patients with radiologically aggressive lung cancer, no significant statistical differences in 5-year recurrence-free (81% vs 90%; P = 0.33) and overall (88% vs 93%; P = 0.76) survival comparing lobectomy (n = 392) to segmentectomy (n = 130) were observed. Among 115 propensity-matched pairs, 5-year recurrence-free survival and overall survival were similar between patients who underwent lobectomy and those who underwent segmentectomy (83.3% and 88.3% vs 90.9% and 94.5%, respectively).

CONCLUSIONS

Difference in survival was not identified with segmentectomy and lobectomy in patients with radiologically aggressive small-sized lung cancer with high risk of recurrence.

Role of soluble receptor for advanced glycation end products in postoperative fibrotic lung injury

BACKGROUND

In lung cancer patients with interstitial lung disease, postoperative acute exacerbation can be fatal. However, the predictive biomarkers for postoperative exacerbation of interstitial lung disease have not been fully elucidated. The soluble receptor for advanced glycation end products is a lung-derived anti-inflammatory protein, which can prevent acute lung injury. This study aimed to elucidate its role in this fatal complication, especially focusing on the predictive potential of serum levels of soluble receptor for advanced glycation end products.

METHODS

We retrospectively enrolled 152 patients with lung cancer and interstitial lung disease who underwent lung resection and had blood samples collected before surgery. Independent predictors of postoperative acute exacerbation were evaluated in all patients and in subgroups based on the surgical procedure. Additionally, serial changes in soluble receptor levels in these subgroups were evaluated.

RESULTS

Seventeen (11.2%) patients developed postoperative acute exacerbation. Receiver operating characteristic curve analysis revealed 547.4 pg/mL as the optimal soluble receptor level cut-off value. Univariate and multivariate logistic regression analyses revealed a significant association between soluble receptor serum levels (≤547.4 pg/mL) and postoperative acute exacerbation. In the subgroup analysis, this independent association was observed only in the lobectomy group. Additionally, lobectomy caused a significant reduction in postoperative soluble receptor levels.

CONCLUSIONS

Decreased baseline levels of circulatory soluble receptor might be a potential risk factor for postoperative acute exacerbation in patients with lung cancer and interstitial lung disease. Besides, additional reduction in the levels of this anti-inflammatory protein occurs owing to the lung resection.

Serum S100 calcium-binding protein A4 as a novel predictive marker of acute exacerbation of interstitial pneumonia after surgery for lung cancer

BACKGROUND

Acute exacerbation (AE) of interstitial pneumonia (IP) is the most fatal complication after lung resection for lung cancer. To improve the prognosis of lung cancer with IP, the risk factors of AE of IP after lung resection should be assessed. S100 calcium-binding protein A4 (S100A4) is a member of the S100 family of proteins and is a known marker of tissue fibrosis. We examined the usefulness of S100A4 in predicting AE of IP after lung resection for lung cancer.

METHODS

This study included 162 patients with IP findings on preoperative high-resolution computed tomography scan who underwent curative-intent lung resection for primary lung cancer between April 2007 and March 2019. Serum samples were collected preoperatively. Resected lung tissue from 76 patients exhibited usual IP (UIP) pattern in resected lung were performed immunohistochemistry (IHC). Relationship between S100A4 and the incidence of AE of IP and short-term mortality was analyzed.

RESULTS

The receiver operating characteristic area under the curve for serum S100A4 to predict postoperative AE of IP was 0.871 (95% confidence interval [CI], 0.799-0.943; P < 0.001), with a sensitivity of 93.8% and a specificity of 75.3% at the cutoff value of 17.13 ng/mL. Multivariable analysis revealed that a high serum S100A4 level (> 17.13 ng/mL) was a significant risk factor for AE of IP (odds ratio, 42.28; 95% CI, 3.98-449.29; P = 0.002). A 1-year overall survival (OS) was significantly shorter in patients with high serum levels of S100A4 (75.3%) than in those with low serum levels (92.3%; P = 0.003). IHC staining revealed that fibroblasts, lymphocytes, and macrophages expressed S100A4 in the UIP area, and the stroma and fibrosis in the primary tumor expressed S100A4, whereas tumor cells did not.

CONCLUSIONS

Serum S100A4 had a high predictive value for postoperative AE of IP and short-term mortality after lung resection.

The impact of pathological lymph node metastasis with lymphatic invasion on the survival of patients with clinically node-negative non-small cell lung cancer: A multicenter study

OBJECTIVES

Lymphatic vessel invasion (Ly) plays a crucial role in pathological lymph node metastasis (pN), and we consider pN + Ly + disease to indicate a high affinity for the lymphatic system. This study evaluated the outcomes of patients with clinically node-negative (N0) non-small cell lung cancer (NSCLC) who presented with pN + with Ly+.

MATERIALS AND METHODS

This retrospective study evaluated 1775 patients with clinically N0 stage I-III NSCLC who underwent R0 anatomical resection and systematic lymph node dissection at three institutions between January 2010 and December 2017. Patients were classified into four groups according to their pN and Ly statuses. Univariable and multivariable analyses were performed to identify factors associated with poor recurrence-free survival (RFS) and pN + Ly+.

RESULTS

Kaplan-Meier curves revealed that the 5-year RFS rates were 90.8 % for pN-Ly- patients, 55.6 % for pN-Ly + patients, 63.4 % for pN + Ly- patients, and 41.3 % for pN + Ly + patients. Distant and lymph node recurrences were more common in the pN + Ly + group, relative to in the pN-Ly- and pN-Ly + groups (both p < 0.001). Multivariable analyses revealed that pN and Ly statuses were independently associated with RFS, while the solid tumor size and maximum standardized uptake value were independently associated with pN + Ly + status. The proportion of pN + Ly + disease was 17.2 % in patients with a solid-part size of > 1.80 cm and a SUVmax of > 3.55.

CONCLUSION

pN and Ly statuses were independent prognostic factors in patients with clinically N0 stage I-III NSCLC. Diseases presenting with pN + with Ly + were associated with increased rates of distant and lymph node recurrence.

Complex Segmentectomy for Hypermetabolic Clinical Stage IA Non-Small Cell Lung Cancer

BACKGROUND

Due to its invasiveness, the indications for "complex segmentectomy" for radiologically hypermetabolic (high maximum standard uptake value [SUV max]) non-small cell lung cancer (NSCLC) remains controversial. This study compared the outcomes after complex segmentectomy and lobectomy in these patients.

METHODS

We retrospectively reviewed 717 patients with radiologically hypermetabolic (SUV max ≥ 2.5), clinical Stage IA NSCLC who underwent complex segmentectomy (n = 61) or "location-adjusted" lobectomy (n = 656) at three institutions from 2010 to 2019. Postoperative outcomes were analyzed for all patients and their propensity score-matched pairs. Factors affecting oncologic outcomes were assessed by Kaplan-Meier estimates and Cox proportional hazards regression analyses.

RESULTS

The prognosis of patients undergoing complex segmentectomy was not significantly different from that of patients undergoing lobectomy [5-year cancer specific survival (CSS) rate, 89.9% vs. 91.1%, P = 0.98 and 5-year recurrence-free interval (RFI) rates, 83.0% vs. 77.5%, P = 0.62] in non-adjusted cohort. In 55 propensity score-matched pairs, oncologic outcomes were not significantly different between patients undergoing complex segmentectomy (5-year CSS, 89.9%; 5-year RFI, 83.0%) and lobectomy (5-year CSS, 83.6%; 5-year RFI, 82.5%). Multivariable Cox regression analysis for RFI revealed no significant differences between oncologic outcomes associated with complex segmentectomy and lobectomy (hazard ratio, 0.84; 95% confidence interval, 0.25-2.14; P = 0.74).

CONCLUSIONS

Oncologic outcomes of complex segmentectomy and lobectomy were not significantly different in those with radiologically hypermetabolic, clinical Stage IA NSCLC patients. Complex segmentectomy can treat high SUV max, clinical Stage IA lung cancers without compromising oncologic results.

Survival of Octogenarians with Early-Stage Non-small Cell Lung Cancer is Comparable Between Wedge Resection and Lobectomy/Segmentectomy: JACS1303

BACKGROUND

Anatomic resection with lymph node dissection or sampling is the standard treatment for early non-small cell lung cancer (NSCLC), and wedge resection is an option for compromised patients. This study aimed to determine whether wedge resection can provide comparable prognoses for elderly patients with NSCLC.

METHODS

The study analyzed the clinicopathologic findings and surgical outcomes during a median follow-up period of 39.6 months for 156 patients with solid dominant (consolidation-to-tumor ratio > 0.5) small (whole tumor size ≤ 2 cm) NSCLC among 892 patients 80 years of age or older with medically operable lung cancer between April 2015 and December 2016.

RESULTS

The 3-year overall survival (OS) rates after wedge resection and after segmentectomy plus lobectomy did not differ significantly (86.5 %; 95 % confidence interval [CI], 74.6-93.0 % vs 83.7 % 95 % CI, 74.0-90.0 %; P = 0.92). Multivariable Cox regression analysis of OS with propensity scores showed that the surgical procedure was not an independent prognostic predictor (hazard ratio [HR], 0.84; 95 % CI, 0.39-1.8; P = 0.64). The 3-year OS rates were slightly better after wedge resection for 97 patients who could tolerate lobectomy than after segmentectomy plus lobectomy (89.4 %; 95 % CI, 73.8-95.9 % vs 75.8 %; 95 % CI, 62.0-85.2 %; P = 0.14). The cumulative incidence of other causes for death was marginally higher after segmentectomy plus lobectomy than after wedge resection (P = 0.079).

CONCLUSIONS

Wedge resection might be equivalent to lobectomy or segmentectomy for selected patients 80 years of age or older with early-stage NSCLC who can tolerate lobectomy.

Appropriate Extent of Lymphadenectomy in Segmentectomy: A Multicenter Study

BACKGROUND

The significance of lymphadenectomy is yet to be fully examined in segmentectomy. We compared the oncological outcomes of mediastinal lymph node dissection (LND) and hilar LND for lung cancer treated with segmentectomy via a multicenter database using propensity score-matched analysis.

METHODS

We reviewed 357 clinical stage IA radiologically solid-dominant lung cancer patients who underwent segmentectomy with lymphadenectomy. The extent of LND was classified into systematic/lobe-specific mediastinal LND and hilar LND only groups. Postoperative results after segmentectomy with mediastinal LND (n = 179) and hilar LND (n = 178) were analyzed for all patients and their propensity score-matched pairs.

RESULTS

Cancer-specific survival (CSS) and recurrence-free interval (RFI) rates for the mediastinal LND group were determined to be not significantly different compared with the hilar LND group in all non-adjusted cohorts. In the propensity score-matched cohort (129 pairs), mediastinal LND harvested more lymph nodes compared with hilar LND, and both groups had significantly different pathological stages (P = 0.015). Adjuvant chemotherapy was performed in 10 (7.8%) patients in the mediastinal LND group and 4 (3.1%) in the hilar LND group. The mediastinal LND group tended to have better prognosis than the hilar LND group (5-year CSS rates, 97.4% vs 93.2%; 5-year RFI rates, 93.5% vs 88.5%).

CONCLUSIONS

Mediastinal LND was found to provide more appropriate pathological staging compared with hilar LND in patients with segmentectomy by harvesting more lymph nodes. In addition, mediastinal LND might lead to better oncological outcome than hilar LND in segmentectomy.