Postoperative pulmonary function of patients with lung cancer and interstitial lung abnormalities.

OBJECTIVE: We investigated the impact of radiological interstitial lung abnormalities on the postoperative pulmonary functions of patients with non-small cell lung cancer. METHODS: A total of 1191 patients with clinical stage IA non-small cell lung cancer who underwent lung resections and pulmonary function tests ≥ 6 months postoperatively were retrospectively reviewed. Postoperative pulmonary function reduction rates were compared between patients with and without interstitial lung abnormalities and according to the radiological interstitial lung abnormality classifications. Surgical procedures were divided into wedge resection, 1-2 segment resection, and 3-5 segment resection groups. RESULTS: No significant differences in postoperative pulmonary function reduction rates 6 months after wedge resection were observed between the interstitial lung abnormality [n = 202] and non-interstitial lung abnormality groups [n = 989] [vital capacity [VC]: 6.82% vs. 5.00%; forced expiratory volume in 1 s [FEV1]: 7.05% vs. 7.14%]. After anatomical resection, these values were significantly lower in the interstitial lung abnormality group than in the non-interstitial lung abnormality group [VC: 1-2 segments, 12.50% vs. 9.93%; 3-5 segments, 17.42% vs. 14.23%; FEV1: 1-2 segments: 13.36% vs. 10.27%; 3-5 segments: 17.36% vs. 14.39%]. No significant differences in postoperative pulmonary function reduction rates according to the radiological interstitial lung abnormality classifications were observed. CONCLUSIONS: The presence of interstitial lung abnormalities had a minimal effect on postoperative pulmonary functions after wedge resections; however, pulmonary functions significantly worsened after segmentectomy or lobectomy, regardless of the radiological interstitial lung abnormality classification in early-stage non-small cell lung cancer.

The Role of Emphysema on Postoperative Prognosis in Early-Stage Nonsmall Cell Lung Cancer.

BACKGROUND: Emphysema is generally considered a poor prognostic factor for patients with nonsmall cell lung cancer; however, whether the poor prognosis is due to highly malignant tumors or emphysema itself remains unclear. This study was designed to determine the prognostic value of emphysema in patients with early-stage nonsmall cell lung cancer. METHODS: A total of 721 patients with clinical stage IA nonsmall cell lung cancer who underwent complete resection between April 2007 and December 2018 were retrospectively analyzed regarding clinicopathological findings and prognosis related to emphysema. RESULTS: The emphysematous and normal lung groups comprised 197 and 524 patients, respectively. Compared with the normal lung group, lymphatic invasion (23.9% vs. 14.1%, P = 0.003), vascular invasion (37.6% vs. 17.2%, P < 0.001), and pleural invasion (18.8% vs. 10.9%, P = 0.006) were observed more frequently in the emphysema group. Additionally, the 5-year overall survival rate was lower (77.1% vs. 91.4%, P < 0.001), and the cumulative incidence of other causes of death was higher in the emphysema group (14.0% vs. 3.50%, P < 0.001). Multivariable Cox regression analysis of overall survival revealed that emphysema (vs. normal lung, hazard ratio 2.02, P = 0.0052), age > 70 years (vs. < 70 years, hazard ratio 4.03, P < 0.001), and SUVmax > 1.8 (vs. ≤ 1.8, hazard ratio 2.20, P = 0.0043) were independent prognostic factors. CONCLUSIONS: Early-stage nonsmall cell lung cancer with emphysema has a tendency for the development of highly malignant tumors. Additionally, emphysema itself may have an impact on poor prognosis.

The Tumor Immune Microenvironment Is Associated With Recurrence in Early-Stage Lung Adenocarcinoma.

Introduction: Immune checkpoint inhibitors have recently been approved for the treatment of early-stage NSCLC in the perioperative setting on the basis of phase 3 trials. However, the characteristics of such patients who are susceptible to recurrence after adjuvant chemotherapy or who are likely to benefit from postoperative immunotherapy have remained unclear. Methods: This biomarker study (WJOG12219LTR) was designed to evaluate cancer stem cell markers (CD44 and CD133), programmed death-ligand 1 (PD-L1) expression on tumor cells, CD8 expression on tumor-infiltrating lymphocytes, and tumor mutation burden in completely resected stage II to IIIA NSCLC with the use of archived DNA and tissue samples from the prospective WJOG4107 trial. Tumors were classified as inflamed or noninflamed on the basis of the PD-L1 tumor proportion score and CD8+ tumor-infiltrating lymphocyte density. The association between each potential biomarker and relapse-free survival (RFS) during adjuvant chemotherapy was assessed by Kaplan-Meier analysis. Results: A total of 117 patients were included in this study. The median RFS was not reached (95% confidence intervals [CI]: 22.4 mo-not reached; n = 39) and 23.7 months (95% CI: 14.5-43.6; n = 41) in patients with inflamed or noninflamed adenocarcinoma, respectively (log-rank p = 0.02, hazard ratio of 0.52 [95% CI: 0.29-0.93]). Analysis of the combination of tumor inflammation category and TP53 mutation status revealed that inflamed tumors without TP53 mutations were associated with the longest RFS. Conclusions: PD-L1 expression on tumor cells, CD8+ T cell infiltration, and TP53 mutation status may help identify patients with early-stage NSCLC susceptible to recurrence after adjuvant chemotherapy.

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.

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.

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.

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.

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.

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.

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.

SPARC Is a Novel Positive Immunohistochemical Marker of Epithelioid Mesothelioma to Differentiate It From Lung Adenocarcinoma and/or Squamous Cell Carcinoma.

Epithelioid mesothelioma with a solid histologic pattern (solid epithelioid mesothelioma) is difficult to distinguish from a poorly differentiated squamous cell lung carcinoma and/or solid lung adenocarcinoma. Thus, immunohistochemical markers are essential for diagnosis; however, the sensitivity and specificity of pre-existing mesothelial markers are suboptimal, particularly for differentiation from squamous cell carcinoma. Using a cancer-dependency map, we analyzed gene expression data of pleural mesothelioma and non-small cell lung cancer cell lines (squamous cell carcinoma and adenocarcinoma) and identified secreted protein acidic and cysteine-rich (SPARC) as a promising candidate for the differential diagnosis of epithelioid mesothelioma from lung squamous cell carcinoma and/or lung adenocarcinoma. SPARC expression in mesothelioma and lung cancer cell lines was validated using reverse-transcription polymerase chain reaction, western blotting, and immunohistochemistry. Immunohistochemical staining was performed using anti-SPARC antibodies against solid epithelioid mesothelioma, solid lung adenocarcinoma, and poorly differentiated lung squamous cell carcinoma. SPARC positivity was seen in 42/45 (93.3%) of solid epithelioid mesothelioma, 2/40 (5%) solid lung adenocarcinoma, and 2/45 (4.5%) of lung squamous cell carcinomas. The sensitivity, specificity, and diagnostic accuracy for differentiating solid epithelioid mesothelioma from lung cancer (solid lung adenocarcinoma and poorly differentiated lung squamous cell carcinoma) were 93.3, 95.2, and 94.6%, respectively. In conclusion, SPARC is a novel mesothelial marker that can be used to differentiate epithelioid mesothelioma from squamous cell carcinoma and lung adenocarcinoma.

Musashi-1 Is a Novel Immunohistochemical Marker of Neuroendocrine Carcinoma of the Lung.

Small cell lung cancer (SCLC) and large cell neuroendocrine carcinoma (LCNEC) have recently been grouped as lung neuroendocrine carcinomas (NECs). Because these lung NECs are clinically malignant and their treatment strategies differ from those of non-SCLC, the quality of diagnosis has a significant prognostic impact. The diagnosis of LCNEC requires positive immunohistochemical staining with chromogranin A, synaptophysin, and CD56, along with a morphological diagnosis, and insulinoma-associated protein 1 (INSM1) has been proposed as an additional marker but is still not an ideal or better marker. We investigated Musashi-1 as a novel immunohistochemical marker in 42 patients with SCLCs and 44 with LCNECs who underwent lung resection between 1998 and 2020 at our institution. We found Musashi-1 expression in 98% (41/42) SCLC and in 90% (40/44) LCNEC. These findings were similar to CD56 expression and superior to synaptophysin, chromogranin A, and INSM1. Musashi-1 also tended to show more diffuse and intense staining, especially in LCNEC, with more cases staining > 10% than any other existing markers (Musashi-1, 77%; INSM1, 45%; chromogranin A, 34%; synaptophysin, 41%; and CD56, 66%). In conclusion, we identified Musashi-1 as a novel immunohistochemical staining marker to aid in the diagnosis of lung NEC.

Preoperative predictors for recurrence sites associated with poor post-recurrence survival after surgery of non-small cell lung cancer: a multicenter study.

BACKGROUND: The recurrence site that influences post-recurrence survival (PRS) in patients with non-small cell lung cancer (NSCLC) undergoing surgery and the preoperative predictors of recurrence remain unclear. METHODS: Cohorts 1 and 2 had 4520 (who underwent complete resection for p-stage 0-IIIA NSCLC) and 727 (who experienced recurrence after surgery) patients, respectively. The initial sites of recurrence were the lungs (309 cases), thoracic lymph nodes (225 cases), pleura (112 cases), bone (110 cases), central nervous system (86 cases), adrenal gland (25 cases), abdomen (60 cases), cervical and axillary lymph nodes (38 cases), chest wall (13 cases), skin (5 cases), and eye and tongue (3 cases). For cohort 2 analysis, the initial recurrence site that resulted in poor PRS was analyzed by multivariable analysis using a Cox proportional hazard model. For cohort 1 analysis, the preoperative predictors of recurrence patterns with poor PRS were analyzed by multivariable analysis using a logistic regression model. RESULTS: In cohort 2 analysis, recurrence in the central nervous system (hazard ratio [HR], 1.70; p < 0.001), bone (HR, 1.75; p < 0.001), abdomen (HR, 2.39; p < 0.001), and pleura (HR, 1.69; p < 0.001) were independent poor prognostic recurrent sites for PRS and they were high-risk sites (HRS). Intrathoracic lymph nodes, cervical and axillary lymph nodes, lungs, chest wall, adrenal gland, eye and tongue, and skin were low-risk sites (LRS) that did not affect PRS. Patients with multiple LRS without HRS recurrence had a worse prognosis than those with a single LRS without HRS recurrence (5-year PRS 20.2% vs. 37.7%, p < 0.001) and were comparable to those with HRS recurrence (p = 1.000). In cohort 1 analysis, preoperative predictors for HRS and multiple LRS recurrences were positron emission tomography (PET) maximum standardized uptake value (maxSUV) ≥ 3.2 (HR, 5.09; p < 0.001), clinical nodal metastasis (HR, 2.00; p < 0.001), tumor size ≥ 2.4 cm (HR, 1.96; p < 0.001) and carcinoembryonic antigen (CEA) ≥ 5 ng/ml (HR, 1.41; p = 0.004). The cumulative incidence rates of HRS and multiple LRS recurrences within 5 years were 55.9%, 40.9%, 26.3%, 11.1%, and 3.5% (p < 0.001) in patients with 4, 3, 2, 1 and 0 of the above risks, respectively. CONCLUSIONS: HRS and multiple LRS were vital recurrences associated with poor PRS. Preoperative PET maxSUV, clinical nodal metastasis, tumor size, and CEA level predicted the incidence of vital recurrence.

Wedge resection vs. segmentectomy for lung cancer measuring ≤ 2 cm with consolidation tumor ratio > 0.25.

Objectives: We aimed to clarify the differences in prognosis between wedge resection and segmentectomy performed for cN0 non-small cell lung cancer (NSCLC) measuring ≤ 2 cm, with consolidation tumor ratio (CTR) > 0.25. Methods: This multicenter study included 570 patients with cN0 NSCLC (tumor size ≤ 2 cm, CTR > 0.25) who underwent wedge resection (n = 244) and segmentectomy (n = 326) between January 2010 and December 2018. After propensity score matching (PSM, 1:1 method), 182 patients were matched for clinical characteristics (age, sex, laterality, smoking index, tumor size, CTR, carcinoembryonic antigen value, positron-emission tomography-documented maximum standardized uptake value, clinical stage, and tumor disappearance rate) and intergroup comparison of disease-free survival (DFS) and overall survival (OS). Using Gray's test, an intergroup comparison of the cumulative incidence of lung cancer-specific mortality was performed. Results: After PSM, similar DFS (5-year DFS, 79.9% vs. 87.1%, p = 0.103) and OS (5-year OS, 88.7% vs. 88.9%, p = 0.719) rates were observed in the wedge resection and segmentectomy groups. We observed no significant intergroup differences in lung cancer-specific mortality (5-year cumulative incidence: 4.6% vs. 3.5%; p = 0.235). Subgroup analysis revealed no specific subgroup demonstrating improved DFS or OS after undergoing wedge resection or segmentectomy. Conclusion: DFS, OS, and lung cancer-specific mortality were comparable between wedge resection and segmentectomy of cN0 NSCLC-tumor size ≤ 2 cm and CTR > 0.25. Large-scale prospective clinical trials are warranted to compare the prognoses of wedge resection and segmentectomy for these tumors.

Clinicopathologic study of stage I adenosquamous carcinoma of the lung.

OBJECTIVE: Adenosquamous carcinoma of the lung is a characteristic tumor that has both adenocarcinoma and squamous cell carcinoma components. Adenosquamous carcinoma is reported to have an aggressive clinical course, but its clinicopathological features and prognosis are unclear in the early stage. METHODS: Patients who underwent surgical resection for pathological stage I non-small cell lung cancer between April 2009 and December 2014 were retrospectively reviewed. Preoperative and postoperative data, histologic characteristics and outcomes of patients with adenosquamous carcinoma (n = 40) were compared to adenocarcinoma (n = 598) and squamous cell carcinoma (n = 131) patients. Factors affecting prognosis, particularly on recurrence, were assessed via Cox regression analyses. RESULTS: Patients with adenosquamous carcinoma had a worse prognosis than did patients with adenocarcinoma and squamous cell carcinoma in terms of 5 year overall (66.7%) and recurrence-free survival rates (44.9%), as well as a significantly higher recurrence rate (13/40 patients, 32.5%). Multivariable Cox regression analysis for recurrence-free survival rates revealed that the histology of adenosquamous carcinoma was an independent factor for recurrence (hazard ratio: 2.473, 95% confidence interval: 1.328-3.367; P = 0.0004). High serum carcinoembryonic antigen levels (hazard ratio: 5.962) and vascular invasion (hazard ratio: 4.899) were identified as risk factors for recurrence, and patients with adenosquamous carcinoma tended to have distant relapses, such as in the brain. CONCLUSIONS: Early-stage adenosquamous carcinoma of the lung is a histological type associated with severe prognosis and postoperative recurrence, often in distant sites, in approximately one-third of cases. High serum carcinoembryonic antigen levels and vascular invasion might be risk factors of recurrence.

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.

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.