Prognostic impact of spread through air spaces in patients with ≤2 cm stage IA lung adenocarcinoma.

Background: In 2015, the World Health Organization (WHO) included spread through air space (STAS) as a new invasive mode of lung cancer. As a new mode of lung cancer dissemination, STAS has a significant and negative impact on patient prognosis. The surgical approach as well as lymph node dissection (LND) for STAS-positive patients is currently unclear. The aim of this study was to investigate the impact of different surgical approaches to STAS and LND on the prognosis of patients with ≤2 cm stage IA lung adenocarcinoma (LUAD). This study also investigated the possible relationship between STAS and the micropapillary histological subtype and its impact on patient prognosis. Methods: A total of 212 patients with LUAD were included in this study from January 2016 to December 2017, and the overall survival (OS) of the patients was compared. The chi-square test and t-test were applied to compare the clinicopathological data of the patients, and the Cox model was used for the multivariate survival analysis. Results: Of the 212 patients, 93 (43.9%) were STAS positive. The univariate analysis showed that the surgical approach, LND type, micropapillary pattern (MP), solid pattern, and STAS were risk factors for OS. The multivariate analysis showed that the surgical approach, MP, and STAS were risk factors for OS. The STAS-positive patients who underwent lobectomy had a better prognosis than those who underwent sublobar resection; however, there was no significant difference between the two surgical procedures in the STAS-negative group. Additionally, the STAS-positive patients who underwent systematic lymph node dissection (SLND) had a better prognosis than those who underwent limited lymph node dissection (LLND); however, there was no significant difference between the two LNDs in the STAS-negative group. Conclusions: STAS plays an important role in patient prognosis and is an independent risk factor for OS of patients with ≤2 cm stage IA LUAD. When STAS is positive, the choice of lobectomy with SLND may result in a better long-term prognosis for patients.

Differences in postoperative prognosis between early-stage lung adenocarcinoma and squamous cell carcinoma.

BACKGROUND: Although prognosis and treatments differ between small-cell- and nonsmall-cell carcinoma, comparisons of the histological types of NSCLC are uncommon. Thus, we investigated the oncological factors associated with the prognosis of early-stage adenocarcinoma and squamous cell carcinoma. METHODS: We retrospectively compared the clinicopathological backgrounds and postoperative outcomes of patients diagnosed with pathological stage I-IIA adenocarcinoma and squamous cell carcinoma primary lung cancer completely resected at our department from January 2007 to December 2017. Multivariable Cox regression analysis for overall survival and recurrence-free survival was performed. RESULTS: The median follow-up duration was 55.2 months. The cohort consisted of 532 adenocarcinoma and 96 squamous cell carcinoma patients. A significant difference in survival was observed between the two groups, with a 5-year overall survival rate of 90% (95% confidence interval 86-92%) for adenocarcinoma and 77% (95% CI 66-85%) for squamous cell carcinoma (P < 0.01) patients. Squamous cell carcinoma patients had worse outcomes compared to adenocarcinoma patients in stage IA disease, but there were no significant differences between the two groups in stage IB or IIA disease. In multivariate analysis, invasion diameter was associated with overall survival in adenocarcinoma (hazard ratio 1.76, 95% confidence interval 1.36-2.28), but there was no such association in squamous cell carcinoma (hazard ratio 0.73, 95% confidence interval 0.45-1.14). CONCLUSIONS: The importance of tumor invasion diameter in postoperative outcomes was different between adenocarcinoma and squamous cell carcinoma. Thus, it is important to consider that nonsmall-cell carcinoma may have different prognoses depending on the histological type, even for the same stage.

A Multi-Institutional, Randomized, Phase III Trial Comparing Anatomical Segmentectomy and Lobectomy for Clinical Stage IA3 Pure-Solid Non-Small-Cell Lung Cancer: West Japan Oncology Group Study WJOG16923L (STEP UP Trial).

INTRODUCTION: Although the standard treatment for patients with resectable early-stage non-small-cell lung cancer (NSCLC) is pulmonary lobectomy, recent clinical trials have demonstrated the efficacy of anatomical segmentectomy for small-sized early-stage NSCLC measuring ≤2 cm. Segmentectomy is gaining attention as an alternative procedure to lobectomy for early-stage NSCLC. PATIENTS AND METHODS: In January 2024, we have initiated a randomized phase III trial in Japan to confirm the noninferiority of anatomical segmentectomy to lobectomy in patients with peripheral clinical stage IA3 pure-solid NSCLC (tumor measuring >2 cm and ≤3 cm; consolidation-to-tumor ratio = 1.0). We plan to enroll 520 patients from 61 institutions over a period of 5 years. The primary endpoint is overall survival, and the secondary endpoints include relapse-free survival, postoperative respiratory function, proportion of patients with respiratory failure and cerebrovascular disease, cumulative incidence of death from other diseases, cumulative incidence of local recurrence, proportion of patients who undergo segmentectomy, number of resected segments, operative time, blood loss, and adverse events. This trial has been registered in the UMIN Clinical Trials Registry under the code UMIN000052064. CONCLUSIONS: This trial will help establish a novel treatment strategy for patients with peripheral clinical stage IA3 pure-solid NSCLC.

A case of late-onset bleeding from an intercostal artery pseudoaneurysm after hemostasis using soft coagulation.

BACKGROUND: The use of soft coagulation is becoming common in thoracic surgery. Soft coagulation provides rapid hemostasis from small vessels during surgery by dehydrating tissue and denaturing proteins, without burning the tissue. CASE PRESENTATION: A 68-year-old man, with a history of right lower lobectomy 3 years prior, underwent a partial resection of the right upper lobe for a pulmonary nodule suspicious for secondary lung cancer. During the surgery, dissection of the adhesion caused a bleeding from the 6th intercostal artery, and hemostasis was achieved using soft coagulation (some degree of tissue carbonization was noticed at later mortality and morbidity conference). He experienced hemoptysis at postoperative day 18 and was transferred to our hospital. Contrast-enhanced CT scan revealed bleeding from the pseudoaneurysm of the 6th intercostal artery. Embolization was performed by angiography to stop the bleeding. CONCLUSIONS: We experienced a case of late-onset bleeding from a pseudoaneurysm related to soft coagulation hemostasis. Lessons learned from this patient are that additional hemostasis, such as ligation, would be considered for small arteries after hemostasis has been achieved by soft coagulation, especially when some degree of tissue carbonization is suspected.

Segmentectomy versus lobectomy in small-sized peripheral non-small-cell lung cancer with radiologically pure-solid appearance in Japan (JCOG0802/WJOG4607L): a post-hoc supplemental analysis of a multicentre, open-label, phase 3 trial.

BACKGROUND: Although segmentectomy was better than lobectomy in terms of overall survival for patients with non-small-cell lung cancer (NSCLC) with a pure-solid tumour appearance on thin-section CT in the open-label, multicentre, randomised, controlled, phase 3 JCOG0802/WJOG4607L trial, the reasons why segmentectomy was associated with better overall survival were unclear. We aimed to compare the survival, cause of death, and recurrence patterns after segmentectomy versus lobectomy in trial participants with NSCLC with a pure-solid appearance METHODS: We conducted a post-hoc supplemental analysis of the JCO0802/WJOG4607L randomised, controlled, non-inferiority trial for the patients (aged 20-85 years) with small-sized NSCLC with radiologically pure-solid appearance on thin-section CT (≤2 cm, consolidation tumour ratio 1·0). The primary aim was to compare the overall and relapse-free survival, cause of death, and recurrence patterns associated with segmentectomy and lobectomy for patients with radiologically pure-solid NSCLC to determine why the overall survival of segmentectomy was superior to that of lobectomy, even for oncologically invasive lung cancers. JCO0802/WJOG4607L is registered with the UMIN Clinical Trials Registry, UMIN000002317, and is complete. FINDINGS: Between Aug 10, 2009, and Oct 21, 2014, 1106 patients were randomly assigned to undergo either lobectomy or segmentectomy. Of these participants, 553 (50%) had radiologically pure-solid NSCLC and were eligible for this post-hoc supplemental analysis. Of these 553 participants, 274 (50%) patients underwent lobectomy and 279 (50%) underwent segmentectomy. Median patient age was 67 years (IQR 61-73), 347 (63%) of 553 patients were male and 206 (37%) were female, and data on race and ethnicity were not collected. As of data cutoff (June 13, 2020), after a median follow-up of 7·3 years (IQR 6·0-8·5), the 5-year overall survival rate was significantly higher after segmentectomy than after lobectomy (86·1% [95% CI 81·4-89·7] in the lobectomy group, with 55 deaths vs 92·4% [88·6-95·0] in the segmentectomy group, with 38 deaths; hazard ratio (HR) 0·64 [95% CI 0·41-0·97]; log-rank test p=0·033), whereas the 5-year relapse-free survival was similar between the groups (81·7% [95% CI 76·5-85·8], with 34 events vs 82·0% [76·9-86·0], with 52 events; HR 1·01 [95% CI 0·72-1·42]; p=0·94). Deaths after a median follow-up of 7·3 years due to lung cancer occurred in 20 (7%) of 274 patients after lobectomy and 19 (7%) of 279 after segmentectomy, and deaths due to other causes occurred in 35 (13%) patients after lobectomy compared with 19 (7%) after segmentectomy (lung cancer death vs other cause of death, p=0·19). The locoregional recurrence was higher after segmentectomy (21 [8%] vs 45 [16%]; p=0·0021). In subgroup analyses, better 5-year overall survival after segmentectomy than after lobectomy was observed in the subgroup of patients aged 70 years or older (77·1% [95% CI 68·2-83·8] with lobectomy vs 85·6% [77·5-90·9] with segmentectomy; p=0·013) and in male patients (80·5% [73·7-85·7] vs 92·1% [87·0-95·2]; p=0·0085). By contrast, better 5-year relapse-free survival after lobectomy than after segmentectomy was observed in the subgroup younger than 70 years (87·4% [95% CI 81·2-91·7] with lobectomy vs 84·4% [77·9-89·1] with segmentectomy; p=0·049) and in female patients (94·2% [87·6-97·4] vs 82·2% [73·2-88·4]; p=0·047). INTERPRETATION: This post-hoc analysis showed improved overall survival after segmentectomy in patients with pure-solid NSCLC compared with lobectomy. However, survival outcomes of segmentectomy depend on the patient's age and sex. Given the results of this exploratory analysis, further research is necessary to determine clinically relevant indications for segmentectomy in radiologically pure-solid NSCLC. FUNDING: Japanese National Cancer Center Research and Development Fund and Practical Research for Innovative Cancer Control Fund, and a Grant-in-Aid for Scientific Research from the Ministry of Health, Labor, and Welfare of Japan.

Secondary Mutations of the EGFR Gene That Confer Resistance to Mobocertinib in EGFR Exon 20 Insertion.

INTRODUCTION: Approximately 10% of mutations in the EGFR gene in NSCLC are in-frame insertions in exon 20 (X20ins). These tumors usually do not respond to conventional EGFR tyrosine kinase inhibitors (TKIs). Several novel EGFR TKIs active for X20ins are in clinical development, including mobocertinib, which was recently approved by the U.S. Food and Drug Administration. However, acquired resistance during treatment with these TKIs still occurs as in the case of EGFR TKIs of earlier generations. METHODS: We chronically exposed murine pro-B-cell line cells transduced with the five most common X20ins (A763_Y764insFQEA, V769_D770insASV, D770_N771insSVD, H773_V774insNPH and H773_V774insH) to mobocertinib in the presence of N-ethyl-N-nitrosourea and searched for secondary EGFR mutations. We evaluated the efficacies of several EGFR X20ins inhibitors, including zipalertinib and sunvozertinib, against cells with acquired resistant mutations. RESULTS: All secondary mutations resulting in acquired resistance to mobocertinib were exclusively C797S in insFQEA and insSVD. However, in the case of other X20ins (insASV, insNPH, and insH), T790M or C797S secondary mutations contributed to acquired resistance to mobocertinib. The emergence of T790M was more frequent in cells treated with lower drug concentrations. Sunvozertinib exhibited good activity against resistant cells with T790M. Cells with C797S were refractory to all EGFR TKIs, except for erlotinib, which was active for insFQEA with C797S. CONCLUSIONS: T790M or C797S, depending on the original X20ins mutations, conferred acquired resistance to mobocertinib. Sunvozertinib may be the treatment of choice for patients with tumors resistant to mobocertinib because of T790M.

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.

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.

Segmentectomy for patients with early-stage pure-solid non-small cell lung cancer.

For decades, lobectomy has been the recommended surgical procedure for non-small cell lung cancer (NSCLC), including for small-sized lesions. However, two recent pivotal clinical trials conducted by the Japanese Clinical Oncology Group/West Japan Oncology Group (JCOG0802/WJOG4607L) and the Cancer and Leukemia Group B (CALGB140503), which compared the survival outcomes between lobectomy and sublobar resection (the JCOG0802/WJOG4607L included only segmentectomy, not wedge resection), demonstrated the efficacy of sublobar resection in patients with early-stage peripheral lung cancer measuring ≤ 2 cm. The JCOG0802/WJOG4607L demonstrated the superiority of segmentectomy over lobectomy with respect to overall survival, implying the survival benefit conferred by preservation of the lung parenchyma. Subsequently, the JCOG1211 also demonstrated the efficacy of segmentectomy, even for NSCLC, measuring up to 3 cm with the predominant ground-glass opacity phenotype. Segmentectomy has become the standard of care for early-stage NSCLC and its indications are expected to be further expanded to include solid lung cancers > 2 cm. However, local control is still a major concern for segmentectomy for higher-grade malignant tumors. Thus, the indications of segmentectomy, especially for patients with radiologically pure-solid NSCLC, remain controversial due to the aggressive nature of the malignancy. In this study, we reviewed previous studies and discussed the efficacy of segmentectomy for patients with such tumors.

Recent Advances in Perioperative Immunotherapies in Lung Cancer.

Several clinical trials have been revolutionizing the perioperative treatment of early-stage non-small cell lung cancer (NSCLC). Many of these clinical trials involve cancer immunotherapies with antibody drugs that block the inhibitory immune checkpoints programmed death 1 (PD-1) and its ligand PD-L1. While these new treatments are expected to improve the treatment outcome of NSCLC patients after pulmonary resection, several major clinical questions remain, including the appropriate timing of immunotherapy (neoadjuvant, adjuvant, or both) and the identification of patients who should be treated with neoadjuvant and/or adjuvant immunotherapies, because some early-stage NSCLC patients are cured by surgical resection alone. In addition, immunotherapy may induce immune-related adverse events that will require permanent treatment in some patients. Based on this fact as well, it is desirable to select appropriate patients for neoadjuvant/adjuvant immunotherapies. So far, data from several important trials have been published, with findings demonstrating the efficacy of adjuvant atezolizumab (IMpower010 trial), neoadjuvant nivolumab plus platinum-doublet chemotherapy (CheckMate816 trial), and several perioperative (neoadjuvant plus adjuvant) immunotherapies (AEGEAN, KEYNOTE-671, NADIM II, and Neotorch trials). In addition to these key trials, numerous clinical trials have reported a wealth of data, although most of the above clinical questions have not been completely answered yet. Because there are so many ongoing clinical trials in this field, a comprehensive understanding of the results and/or contents of these trials is necessary to explore answers to the clinical questions above as well as to plan a new clinical trial. In this review, we comprehensively summarize the recent data obtained from clinical trials addressing such questions.

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.

Performance of Ultra-Rapid Idylla™ EGFR Mutation Test in Non-Small-Cell Lung Cancer and Its Potential at Clinical Molecular Screening.

BACKGROUND: The Idylla™ EGFR Mutation Test is an ultra-rapid single-gene test that detects epidermal growth factor receptor (EGFR) mutations using formalin-fixed paraffin-embedded specimens. Here, we compared the performance of the Idylla EGFR Mutation Test with the Cobas® EGFR Mutation Test v2. METHODS: Surgically resected NSCLC specimens obtained at two Japanese institutions (N = 170) were examined. The Idylla EGFR Mutation Test and the Cobas EGFR Mutation Test v2 were performed independently and the results were compared. For discordant cases, the Ion AmpliSeq Colon and Lung Cancer Research Panel V2 was performed. RESULTS: After the exclusion of five inadequate/invalid samples, 165 cases were evaluated. EGFR mutation analysis revealed 52 were positive and 107 were negative for EGFR mutation in both assays (overall concordance rate: 96.4%). Analyses of the six discordant cases revealed that the Idylla EGFR Mutation Test was correct in four and the Cobas EGFR Mutation Test v2 was correct in two. In a trial calculation, the combination of the Idylla EGFR Mutation Test followed by a multi-gene panel test will reduce molecular screening expenses if applied to a cohort with EGFR mutation frequency >17.9%. CONCLUSIONS: We demonstrated the accuracy and potential clinical utility of the Idylla EGFR Mutation Test as a molecular screening platform in terms of turnaround time and molecular testing cost if applied to a cohort with a high EGFR mutation incidence (>17.9%).

Adjuvant Osimertinib vs. Placebo in Completely Resected Stage IA2-IA3 EGFR-Mutated NSCLC: ADAURA2.

INTRODUCTION: Osimertinib is a third-generation, irreversible, oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that potently and selectively inhibits both EGFR-TKI sensitizing and EGFR T790M resistance mutations, with demonstrated efficacy in EGFR mutation-positive (EGFRm) non-small cell lung cancer (NSCLC), including central nervous system (CNS) metastases. Here we present the rationale and study design for ADAURA2 (NCT05120349), which will evaluate adjuvant osimertinib vs. placebo in patients with stage IA2-IA3 EGFRm NSCLC, following complete tumor resection. PATIENTS AND METHODS: ADAURA2 is a phase III, global, randomized, double-blind, placebo-controlled study. Patients will be adults aged ≥18 years with resected primary nonsquamous NSCLC stage IA2 or IA3 and central confirmation of an EGFR exon 19 deletion or L858R mutation. Patients will be stratified by pathologic risk of disease recurrence (high vs. low), EGFR mutation type (exon 19 deletion vs. L858R) and race (Chinese Asian vs. non-Chinese Asian vs. non-Asian), and randomized 1:1 to receive osimertinib 80 mg once daily (QD) or placebo QD until disease recurrence, treatment discontinuation, or a maximum treatment duration of 3 years. The primary endpoint of this study is disease-free survival (DFS) in the high-risk stratum. Secondary endpoints include DFS in the overall population, overall survival, CNS DFS, and safety. Health-related quality of life and pharmacokinetics will also be evaluated. RESULTS: Study enrolment began in February 2022 and interim results of the primary endpoint are expected in August 2027.

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.

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.

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.

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.