Oncological feasibility of segmentectomy for inner-located lung cancer

Objective

Oncological feasibility of segmentectomy for internal non-small cell lung cancer (NSCLC) has not been assessed adequately. We assessed the oncological feasibility of segmentectomy for inner-located NSCLC by investigating surgical margins and patient prognosis after undergoing the procedure.

Methods

Of the 3555 patients who underwent resection for lung cancer between 2013 and 2019 at our institution, 659 patients who underwent segmentectomy for clinical stage 0 to stage1A NSCLC were included in this study. Patients were separated into 2 groups according to whether the tumor was in the inner or outer third of the lung area. Clinical characteristics and prognoses were retrospectively compared between the groups.

Results

Of the included 659 cases, 183 (27.8%) were inner-located, and 476 (72.2%) had outer-located NSCLC. The surgical margin was significantly shorter in the inner-located group than in the outer group (median, 16 vs 25 mm; P < .001). The 5-year recurrence-free survival and overall survival probabilities were 91.1%/91.8% (P = .530) and 94.1%/95.6% (P = .345) for inner/outer-located groups, respectively. Multivariate analysis showed that clinical stage IA2 or 3 (P = .043), lymphovascular invasion (P < .001), and surgical margins <20 mm (P = .017) were independent prognostic factors for recurrence-free survival. The location of the inner or outer tumors was not related to the prognosis.

Conclusions

For clinical stage 0 to stage1A NSCLC, tumor location in the inner two-thirds of the lung was not associated with prognosis after segmentectomy. Because one of the independent prognostic factors is margin distance, segmentectomy for inner-located NSCLC would be oncologically acceptable when an adequate surgical margin is secured.

Clinical and Prognostic Significance of Glutathione Peroxidase 2 in Lung Adenocarcinoma

BACKGROUND

Glutathione peroxidase 2 (GPX2) is an antioxidant enzyme with an important role in tumor progression in various cancers. However, the clinical significance of GPX2 in lung adenocarcinoma has not been clarified.

METHODS

Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to analyze GPX2 mRNA expression. Then, we conducted immunohistochemistry (IHC) to assess GPX2 expression in specimens acquired from 351 patients with lung adenocarcinoma who underwent surgery at Kyushu University from 2003 to 2012. We investigated the association between GPX2 expression and clinicopathological characteristics and further analyzed the prognostic relevance.

RESULTS

qRT-PCR revealed that GPX2 mRNA expression was notably higher in tumor cells than in normal tissues. IHC revealed that high GPX2 expression (n = 175, 49.9%) was significantly correlated with male sex, smoking, advanced pathological stage, and the presence of pleural, lymphatic, and vascular invasion. Patients with high GPX2 expression exhibited significantly shorter recurrence-free survival (RFS) and overall survival. Multivariate analysis identified high GPX2 expression as an independent prognostic factor of RFS.

CONCLUSIONS

GPX2 expression was significantly associated with pathological malignancy. It is conceivable that high GPX2 expression reflects tumor malignancy. Therefore, high GPX2 expression is a significant prognostic factor of poor prognosis for completely resected lung adenocarcinoma.

Impact of 18F-FDG PET on TNM Staging and Prognosis in Thymic Epithelial Tumors

BACKGROUND

Preoperative fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) of thymic epithelial tumors (TETs) is well known for identifying malignant-grade TETs; however, its predictive power for determining locally advanced tumors, lymph node (LN) metastasis, and prognosis remains unknown.

PATIENTS AND METHODS

We retrospectively evaluated patients with resectable TETs who were preoperatively assessed using 18F-FDG PET from January 2012 to January 2023. The receiver operating characteristic curve was used to evaluate the cutoff value of the maximum standardized uptake value (SUVmax) to predict advanced-stage disease. Recurrence/progression-free survival (RFS/PFS) was analyzed using the Kaplan-Meier method. The staging was classified according to the tumor-node-metastasis system.

RESULTS

Our study included 177 patients; 145 (81.9%) had pathological early-stage TET (stage I or II), and 32 (19.1%) had advanced stage (stage III or IV). The area under the curve value for predicting the advanced stage was 0.903, and the cutoff value was 5.6 (sensitivity 81.3%, specificity 84.8%). SUVmax > 5.6 was associated with worse prognosis for RFS/PFS. LN metastasis was preoperatively detected by FDG uptake in 30.8% of patients with pathological LN positivity, whereas LN metastasis was not pathologically detected in patients with SUVmax < 5.9. In patients with advanced-stage TETs, LN recurrence was more frequent in patients who were preoperatively detected by 18F-FDG PET than those who were not (75.0% versus 7.1%).

CONCLUSIONS

18F-FDG PET is a potentially valuable tool for predicting advanced stage and poor prognosis of recurrence in patients with TETs. SUVmax can help thoracic surgeons to guide them in selecting appropriate therapeutic strategies for TETs.

Granzyme B (GZMB)-Positive Tumor-Infiltrating Lymphocytes in Lung Adenocarcinoma: Significance as a Prognostic Factor and Association with Immunosuppressive Proteins

BACKGROUND

Granzyme B (GZMB) is a serine protease produced by cytotoxic lymphocytes that reflects the activity of anti-tumor immune responses in tumor-infiltrating lymphocytes (TILs); however, the prognostic significance of GZMB+ TILs in lung adenocarcinoma is poorly understood.

METHODS

We analyzed 273 patients with pathological stage (pStage) I-IIIA lung adenocarcinoma who underwent surgery at Kyushu University from 2003 to 2012. We evaluated GZMB+ TIL counts by immunohistochemistry. We set the cut-off values at 12 cells/0.04 mm2 for GZMB+ TILs and divided the patients into GZMB-High (n = 171) and GZMB-Low (n = 102) groups. Then, we compared the clinicopathological characteristics of the two groups and clinical outcomes. Programmed cell death ligand-1 (PD-L1) and indoleamine 2,3-dioxygenase 1 (IDO1) expression in tumor cells was also evaluated, and combined prognostic analyses of GZMB+ TILs with PD-L1 or IDO1 were performed.

RESULTS

GZMB-Low was significantly associated with pStage II-III, PD-L1 positivity, and IDO1 positivity. Disease-free survival (DFS) and overall survival (OS) in the GZMB-Low group were significantly worse than in the GZMB-High group. In multivariable analysis, GZMB-Low was an independent prognostic factor for both DFS and OS. Furthermore, combined prognostic analyses of GZMB+ TILs with PD-L1 or IDO1 showed that GZMB-Low with high expression of these immunosuppressive proteins had the worst prognosis.

CONCLUSIONS

We analyzed GZMB+ TIL counts in lung adenocarcinoma and elucidated its prognostic significance and association with PD-L1 and IDO1. GZMB+ TIL counts might reflect the patient's immunity against cancer cells and could be a useful prognostic marker of lung adenocarcinoma.

Impact of Chronic Obstructive Pulmonary Disease on the Long-term Prognosis of Patients Undergoing Lobectomy for Non-small-cell Lung Cancer: A Propensity Score-matched Analysis

BACKGROUND/AIM

Recent advances in surgery, such as thoracoscopic surgery, have made it possible to treat patients with chronic obstructive pulmonary disease (COPD) more safely than before. This study evaluated the short- and long-term prognosis of lobectomy in non-small cell lung cancer (NSCLC) patients with COPD.

PATIENTS AND METHODS

This retrospective, propensity-matched, cohort analysis was conducted from January 2014 to December 2018. Among 441 patients who underwent lobectomy for NSCLC, 158 (35.8%) had a preoperative diagnosis of COPD. Propensity-matched analysis, incorporating preoperative variables, was used to compare postoperative hospital stay and complications, and long-term prognosis between the groups.

RESULTS

Propensity matching estimated 145 patients in each group. There was no difference between the two groups for length of postoperative hospital stay (12 vs. 11 days, p=0.306). Postoperative complications were more frequent in the COPD group (24.1%) than in the non-COPD group (16.6%), but the difference was not significant (p=0.108). The 5-year overall survival rate was 86.2% in the COPD group and 82.1% in the non-COPD group after matching (p=0.580). The corresponding 5-year recurrence-free survival rate was 72.8% in the COPD group and 67.2% in the non-COPD group after matching (p=0.601).

CONCLUSION

In case of Global Initiative for Chronic Obstructive Lung Disease (GOLD) I/II classification, COPD did not significantly worsen the prognosis of patients with NSCLC after lobectomy.

Role of 18F-FDG PET in selecting candidates for a minimally invasive approach for thymic epithelial tumour resection

OBJECTIVES

We evaluated the potential of preoperative fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) to predict invasive thymic epithelial tumours in patients with computed tomography (CT)-defined clinical stage I thymic epithelial tumours ≤5 cm in size who are generally considered to be candidates for minimally invasive approaches.

METHODS

From January 2012 to July 2022, we retrospectively analysed patients who exhibited tumor-node-metastasis (TNM) clinical stage I thymic epithelial tumours with lesion sizes ≤5 cm as determined by CT. All patients underwent 18F-FDG PET preoperatively. We analysed the association of maximum standardized uptake values (SUVmax) with both the World Health Organization histological classification and the TNM staging classification.

RESULTS

A total of 107 patients with thymic epithelial tumours (thymomas, 91; thymic carcinomas, 14; carcinoids, 2) were evaluated. Nine patients (8.4%) were pathologically upstaged: TNM pathological stage II in three (2.8%), III in four (3.7%), and IV in two (1.9%). Among these nine upstaged patients, five had thymic carcinoma with stage III/IV, three had type B2/B3 thymoma with stage II/III, and one had type B1 thymoma with stage II. SUVmax was a predictive factor that distinguished pathological stage > I thymic epithelial tumours from pathological stage I (best cut-off value, 4.2; area under the curve [AUC] = 0.820) and thymic carcinomas from other thymic tumours (best cut-off value, 4.5; AUC = 0.882).

CONCLUSIONS

Thoracic surgeons should carefully determine the surgical approach for high FDG-uptake thymic epithelial tumours and keep in mind the issues associated with thymic carcinoma and potential combined resections of neighbouring structures.

Feasibility and effectiveness of segmentectomy versus wedge resection for clinical stage I non-small-cell lung cancer

OBJECTIVES

With recent improvements in surgical techniques for segmentectomy, we hypothesized that segmentectomy is feasible and more effective than wedge resection for non-small-cell lung cancer (NSCLC). We compared perioperative and oncological outcomes for segmentectomy and wedge resection.

METHODS

We performed a retrospective analysis of 720 patients who underwent sublobar resection (segmentectomy, 479; wedge resection, 241) for clinical stage 0 or I NSCLC from January 2017 to June 2020. An adequate surgical margin was defined as a surgical margin distance of ≥2 cm or ≥ the total tumour size. Recurrence-free survival (RFS) was estimated using the Kaplan-Meier method for clinical stage IA.

RESULTS

There was no significant difference in the rate of major (grade ≥III) complications between segmentectomy (1.7%) and wedge resection (1.2%) (P = 0.76). The probability of obtaining adequate surgical margins was significantly higher with segmentectomy (71.4%) versus wedge resection (59.5%) (P = 0.002), and the difference was especially prominent for clinical stage IA2 (75.3% vs 56.9%; P = 0.012). Among patients with clinical stage IA, segmentectomy significantly improved the RFS compared with wedge resection (hazard ratio 2.7; 95% confidence interval 1.60-4.61; log-rank P < 0.001). Subgroup analysis based on the tumour status revealed that segmentectomy had a better RFS in clinical stage IA2 (P < 0.001) and in pure-solid tumours (P = 0.022) than wedge resection.

CONCLUSIONS

We demonstrate that segmentectomy is a feasible procedure with comparable safety outcomes and better surgical margins and cancer control than wedge resection, particularly for clinical stage IA2 NSCLC.

Unexpected Histopathological Diagnosis of Placental Transmogrification of the Lung after Bullectomy for Recurrent Spontaneous Pneumothorax: A Case Report and Literature Review

We report a 33-year-old man who presented with recurrent right pneumothorax. Computed tomography (CT) showed the presence of a large bulla with a maximum diameter of 8 cm in the right middle lobe; he subsequently underwent bullectomy. Histopathology revealed that pulmonary parenchyma adjacent to the bulla represented nodular proliferation of clear cells characterized by a papillary structure resembling placental chorionic villi. Immunohistochemically, clear cells were positive for CD10, suggesting placental transmogrification of the lung (PTL). We reviewed 36 surgical cases of PTL, and only 2 cases (5.6%), including our case, were operated for spontaneous pneumothorax. Bullous lesions secondary to PTL tend to appear as unilateral large cystic masses in non-upper lobes, which is atypical for primary spontaneous pneumothorax (PSP). Although PTL is considered a very rare cause of secondary pneumothorax, we must carefully differentiate this condition.

Preoperative prognostic nutritional index level is associated with tumour-infiltrating lymphocyte status in patients with surgically resected lung squamous cell carcinoma

OBJECTIVES

The prognostic nutritional index (PNI) is an indicator of systemic immune-nutritional condition and is a well-known prognostic biomarker in lung cancer patients. Tumour-infiltrating lymphocytes (TILs) is a specific histological feature of cancers, influencing an individual's immunological tumour responses. However, whether PNI can reflect lung cancer patients' prognosis through local immunity such as TIL is unclear.

METHODS

We selected 64 lung squamous cell carcinoma patients who underwent curative operations. We investigated the significance of preoperative PNI level and evaluated the relationship between PNI and immune cells surrounding the lung cancer tissue using immunohistochemical analysis of a cluster of differentiation (CD)3, CD4, CD8 and CD68.

RESULTS

A low-PNI level was significantly associated with a worse postoperative prognosis (P = 0.042). The PNI (hazard ratio 2.768, 95% confidence interval 1.320-5.957; P = 0.007) was an independent prognostic factor. The low-PNI group had a significantly shorter recurrence-free survival and overall survival (P = 0.013 and P = 0.002, log-rank test) compared with the high-PNI group. A significant positive correlation between PNI components including preoperative peripheral blood lymphocyte count and serum albumin concentration, and TILs, was observed. Absolute numbers of TILs in the preoperative high-PNI group were significantly increased compared with those in the preoperative low-PNI group (CD3+ cells; P = 0.002, CD4+ cells; P = 0.049 and CD8+ cells; P = 0.024).

CONCLUSIONS

The preoperative PNI level was strongly associated with the postoperative outcome in lung cancer patients. Considering the positive relationship between preoperative PNI level and TIL status, preoperative immune-nutritional condition may influence lung cancer patients' postoperative prognosis through local immunity as well as systemic immune response.

Mutual checking system for assessing trainee skills of thoracic surgery

BACKGROUND

Video-assisted surgery helps surgeons learn surgical skills efficiently. The aim of this study was to evaluate the effect of mutual evaluation of trainees' surgical techniques using tabulated common evaluation criteria.

METHODS

We created a check sheet in which a standard pulmonary lobectomy procedure was divided into six parts and the checkpoints to note listed. Both the trainees and trainers used tabulated common evaluation criteria to evaluate lobectomies performed by the trainees.

RESULTS

From September 2019 to March 2020, 30 lobectomies were performed by three trainees. The trainee's evaluations of their own procedures were relatively high at first, then decreased, then gradually increased; however, the trainers' evaluations showed no such tendency.

CONCLUSIONS

Mutual evaluation of surgery using tabulated common evaluation criteria enables trainees to review their own surgery objectively and receive evaluations by trainers, thus helping them to avoid the Dunning-Kruger effect and efficiently acquire basic surgical skills.

VATS right apical segmentectomy for lung cancer in a patient with tracheal bronchus

INTRODUCTION

A tracheal bronchus is rarely observed, occurring in only 1% of all patients who undergo thoracic surgeries. We rarely encounter lung cancer in a patient with a tracheal bronchus; however, it is essential to know the distinctive perioperative management strategy for patients with a tracheal bronchus.

CASE PRESENTATION

We report a 72-year-old man with lung cancer located in the right apical segment supplied by a tracheal bronchus. Annual chest computed tomography performed as follow-up after colon cancer resection showed an enlarging pulmonary nodule with pure ground-glass opacity, which was suspected to be lung adenocarcinoma. The nodule was located in the right apical segment. The apical segment was independently supplied by a single pulmonary artery superior trunk and a tracheal bronchus that branched directly from the trachea at 1.2 cm above the carina. The pulmonary vein branching pattern was uncommon in that the central vein that usually runs through B2 (posterior bronchus) and B3 (anterior bronchus) was missing. The patient underwent video-assisted thoracoscopic apical segmentectomy under one-lung ventilation using a left-sided double-lumen tube.

DISCUSSION

Anomalous venous return accompanied with tracheal bronchus has been described in some reports. Since pulmonary vein is important during segmentectomy, the surgeon should pay particular attention to the venous return.

CONCLUSION

Preoperative three-dimensional graphic imagery helped us accurately identify the anatomical anomaly to enable the successful segmentectomy in a patient with a tracheal bronchus. We review the relevant literature regarding the perioperative management of patients with a tracheal bronchus.

Assessment of Intraoperative Microbiological Culture in Patients with Empyema: Comparison with Preoperative Microbiological Culture

Purpose: Assessing microbiological culture results is essential in the diagnosis of empyema and appropriate antibiotic selection; however, the guidelines for the management of empyema do not mention assessing microbiological culture intraoperatively. Therefore, we tested the hypothesis that intraoperative microbiological culture may improve the management of empyema.

Methods: We performed a retrospective analysis of 47 patients who underwent surgery for stage II/III empyema from January 2011 to May 2019. We compared the positivity of microbiological culture assessed preoperatively at empyema diagnosis versus intraoperatively. We further investigated the clinical characteristics and postoperative outcomes of patients whose intraoperative microbiological culture results were positive.

Results: The positive rates of preoperative and intraoperative microbiological cultures were 27.7% (13/47) and 36.2% (17/47), respectively. Among 34 patients who were culture-negative preoperatively, eight patients (23.5%) were culture-positive intraoperatively. Intraoperative positive culture was significantly associated with a shorter duration of preoperative antibiotic treatment (p = 0.002). There was no significant difference between intraoperative culture-positive and -negative results regarding postoperative complications.

Conclusions: Intraoperative microbiological culture may help detect bacteria in patients whose microbiological culture results were negative at empyema diagnosis. Assessing microbiological culture should be recommended intraoperatively as well as preoperatively, for the appropriate management of empyema.

An Adult Case of Multiple Extralobar Pulmonary Sequestrations in the Thoracic and Abdominal Cavities

Extralobar pulmonary sequestration is generally located in the left thoracic cavity and is often identified prenatally or in infants. We experienced a rare case of multiple extralobar pulmonary sequestrations in the thoracic and abdominal cavities, incidentally detected in a 60-year-old woman by cancer screening. The patient underwent surgery by thoracoscopic and laparoscopic approaches simultaneously, and extralobar sequestration was histologically confirmed in each lesion. Preoperative diagnosis was difficult because of unusual multiple localization and an undetectable aberrant artery on imaging examinations.

Interleukin-38 promotes tumor growth through regulation of CD8+ tumor-infiltrating lymphocytes in lung cancer tumor microenvironment

BACKGROUND

Interleukin (IL)-38 was discovered in 2001 and is a member of the IL-1 family of cytokines. IL-38 shows anti-inflammatory activity in several inflammatory diseases. In lung adenocarcinoma, we previously demonstrated that high IL-38 expression in tumor cells was associated with poor prognosis. However, the role of IL-38 in the tumor microenvironment has not been clarified.

METHODS

IL-38-plasmid-transfected Lewis lung carcinoma cells (LLC-IL38) and empty vector-transfected LLC cells (LLC-vector) were established. Cell proliferation in vitro and tumor growth in vivo were examined, and immunohistochemical staining was used to assess tumor-infiltrating lymphocytes (TILs). A CD8⁺ lymphocyte depletion model was established to show the association between IL-38 and CD8⁺ lymphocytes. Moreover, we examined the association between IL-38 expression and CD8⁺ TILs in human samples, analyzing immunohistochemical staining in 226 patients with radically resected lung adenocarcinoma.

RESULTS

Tumor growth of LLC-IL38 in vivo was significantly increased compared with that of LLC-vector, although cell proliferation of LLC-IL38 in vitro was lower than that of LLC-vector. CD8⁺ TILs were significantly decreased in LLC-IL38 tumor compared with LLC-vector tumor. The difference in tumor growth between LLC-IL38 and LLC-vector became insignificant after depletion of CD8⁺ lymphocytes. In immunohistochemical staining in tissues from patients with lung adenocarcinoma, multivariate analysis showed high IL-38 expression was an independent negative predicter of high density of CD8⁺ TILs.

CONCLUSION

We demonstrated that high IL-38 expression in tumor cells was significantly associated with reduction of CD8⁺ TILs and tumor progression. These results suggest that IL-38 could be a therapeutic target for lung cancer.

Interpleural distance predicts persistent air leak after initial primary spontaneous pneumothorax

Background

Initial surgical intervention for a first episode of primary spontaneous pneumothorax (PSP) is controversial. However, if air leak persists after initial drainage, surgical treatment is recommended. Therefore, we investigated risk factors for persistent air leak (PAL) in patients with a first episode of PSP.

Methods

We retrospectively analyzed 122 patients with a first episode of PSP between January 2011 and April 2019. PAL was defined as air leak lasting 72 hours or longer. Early admission was defined hospital admission within 24 hours of symptom onset. Three methods were used to estimate pneumothorax size on chest X-rays taken at admission: interpleural distance, apex-cupola distance, and Light index.

Results

Among 122 patients, 55 developed PAL (PAL group) and 67 did not (non-PAL group). The size of pneumothorax was significantly larger in the PAL group than in the non-PAL group in all three methods of assessment (P<0.001). Early hospital admission was significantly associated with PAL (P=0.026). Logistic regression analysis revealed that the odds ratio for PAL per unit increase in pneumothorax size evaluated with the interpleural distance was 1.304 (P<0.001). Multivariate logistic regression analysis showed that interpleural distance at the hilum and early admission (P<0.001, P=0.008, respectively) were independent predictors of PAL in patients with a first episode of PSP.

Conclusions

In our study, we demonstrated that the interpleural distance at the hilum is a simple and effective predictor of PAL in patients with a first episode of PSP. Our data may help decision-making for initial surgical treatment in these patients.

Impact of Fat-Free Adipose Tissue on the Prevalence of Low Muscle Mass Estimated Using Calf Circumference in Middle-Aged and Older Adults

Previous studies proposed calf circumference cutoff values for predicting dual-energy X-ray absorptiometry (DXA)-derived low muscle mass. However, DXA-derived appendicular lean mass (aLM) includes non-skeletal muscle components such as the appendicular fat-free component of adipose tissue fat cells (aFFAT). The purpose of this study was to compare the calf circumference method of classification before (Model #1) and after (Model #2) eliminating the influence of FFAT in healthy Japanese adults (50 to 79 years; mean age 70 (SD 7) years). Model 1, and Model 2 for classifying low muscle mass had a sensitivity of 78% and 64%, specificity of 76% and 75%, positive predictive value of 31% and 28%, and negative predictive value of 96% and 93%, respectively. Appendicular fat-free component of adipose tissue has the potential to influence the ability of calf circumference to accurately classify individuals with low muscle mass. Consideration should be made when using this as a screening tool for low muscle mass.

The prognostic impact of obstructive lung disease on survival of never smokers with resected non-small-cell lung cancer: a comparison with smokers

OBJECTIVES

The proportion of never smokers among non-small-cell lung cancer (NSCLC) patients has steadily increased in recent decades, suggesting an urgent need to identify the major underlying causes of disease in this cohort. Chronic obstructive pulmonary disease is a risk factor for lung cancer in both smokers and never smokers. The aim of this study was to investigate the association between obstructive lung disease and survival in never smokers and smokers with NSCLC after complete resection.

METHODS

We retrospectively reviewed data from 548 NSCLC patients treated at our institution. The effects of obstructive lung disease on recurrence-free survival and cancer-specific survival following the resection of NSCLC were determined by univariable and multivariable Cox regression analyses.

RESULTS

Among the 548 patients analysed, 244 patients (44.5%) were never smokers and 304 patients (55.4%) were current or former smokers. In the never-smoker group, 48 patients (19.7%) had obstructive lung disease, 185 patients (75.8%) were women and 226 patients (92.6%) had adenocarcinoma. Obstructive lung disease was significantly associated with shorter recurrence-free survival (P = 0.006) and cancer-specific survival (P = 0.022) in the never smokers, but not the smokers, on both univariable and multivariable analyses. The associations between obstructive lung disease and prognosis in never smokers remained significant after propensity score matching.

CONCLUSIONS

Obstructive lung disease is an independent prognostic factor for recurrence-free survival and cancer-specific survival in never smokers, but not in smokers, with NSCLC. Based on this finding, further examination is warranted to advance our understanding of the mechanisms associated with NSCLC in never smokers.

Lorlatinib for the treatment of patients with non-small cell lung cancer

Lorlatinib is a novel third-generation tyrosine kinase inhibitor (TKI) which targets anaplastic lymphoma kinase (ALK) as well as receptor tyrosine kinase c-ros oncogene 1 (ROS1). A critical limitation of conventional ALK/ROS TKIs is their association with acquired resistance mutations (particularly ALK G1202R and ROS1 G2032R) in the ALK or ROS1 gene, although these are not the only resistance mechanisms. Another limitation of this class of drugs is their inadequate efficacy against central nervous system metastasis, likely attributable to the blood-brain barrier (BBB). Therefore, lorlatinib was developed to overcome these limitations by being more potent, selective and permeable to the BBB than previous-generation ALK/ROS1 TKIs and subsequently received breakthrough therapy designation from the U.S. Food and Drug Administration (FDA) in April 2017. In September 2018, Japan became the first country where lorlatinib received approval for treating patients with ALK-rearranged non-small cell lung cancer. Eventually, the FDA approved lorlatinib (Lorbrena; Pfizer) in November 2018. Lorlatinib use is expected to increase in importance, owing to its promising efficacy in clinical trials.

The association and prognostic impact of enhancer of zeste homologue 2 expression and epithelial-mesenchymal transition in resected lung adenocarcinoma

OBJECTIVES

Epithelial-mesenchymal transition (EMT) and the histone methyltransferase Enhancer of Zeste Homologue 2 (EZH2) are important regulators of lung cancer progression and metastasis. Although recent studies support the correlation between EZH2 expression and EMT, no reports have investigated their association using immunohistochemistry or explored their prognostic impact on lung adenocarcinoma. The aim of this study was to elucidate the association between EZH2 and EMT, and their prognostic significance.

METHODS

EZH2 and the EMT markers E-cadherin and Vimentin were examined by IHC in lung adenocarcinoma specimens that were resected from 2003-2012. Associations between EZH2 and EMT markers and their correlations with survival were analyzed.

RESULTS

We enrolled 350 patients, approximately 70% of whom were diagnosed as pathological stage I. The rates of positive E-cadherin, Vimentin, and EZH2 expression were 60.3%, 21.4%, and 52.0%, respectively. There was a significant positive correlation between EZH2 and Vimentin expression (p = 0.008), and EZH2 scores were higher in the Mesenchymal group (p = 0.030). In multivariate analysis, EZH2 was an independent predictor of Vimentin expression, and vice versa. EMT and EZH2 overexpression were significantly correlated with poor disease-free and overall survival. Furthermore, the Epithelial group with high EZH2 expression had significantly worse disease-free and overall survival. Positive staining for EMT markers was unfavorable regarding disease-free survival among patients with low EZH2 expression.

CONCLUSIONS

EMT and high EZH2 expression were associated with poor NSCLC prognoses. Vimentin is a key factor linking EMT and EZH2 in lung adenocarcinoma.

Clinical and Prognostic Significance of the Epithelial-Mesenchymal Transition in Stage IA Lung Adenocarcinoma: A Propensity Score-Matched Analysis

BACKGROUND

The epithelial-mesenchymal transition (EMT) describes the process through which cells lose epithelial characteristics and gain a mesenchymal phenotype. The EMT contributes to tumor invasion and cancer progression, and is associated with metastasis and poor survival of patients with non-small-cell lung cancer. However, little is known about the relationships between the EMT and the clinicopathologic characteristics of patients with stage IA lung adenocarcinoma.

PATIENTS AND METHODS

We conducted immunohistochemical analysis of the expression of the EMT markers E-cadherin and vimentin of specimens acquired from 183 consecutive patients with stage IA lung adenocarcinoma. The clinicopathologic significance of the association of the EMT status with E-cadherin and vimentin expression was analyzed after propensity score matching.

RESULTS

E-cadherin and vimentin were detected in 68.3% and 18.6% of stage IA lung adenocarcinomas, respectively. The presence of cells with EMT conversion was associated with older patient age. A propensity score-matched cohort (128 patients) was used for further analyses. Computed tomography revealed that tumors with EMT conversion showed solid-dominant nodules compared to those without conversion. Survival analysis after propensity score matching showed that the EMT correlated with poor disease-free survival (hazard ratio = 2.57, P = .0451) and overall survival (hazard ratio = 4.23, P = .0471). Multivariate analysis revealed that the EMT was an independent predictor of shorter disease-free survival.

CONCLUSION

The EMT was a significant predictor of poor prognosis of patients with stage IA lung adenocarcinoma. The EMT status may serve as an indicator for administering adjuvant therapy.

Association of Low Body Mass Index With Poor Clinical Outcomes After Resection of Non-small Cell Lung Cancer

BACKGROUND/AIM

This study was performed to evaluate the influence of the body mass index (BMI) on disease-free survival and overall survival (DFS and OS) in patients with resected non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Overall, 546 of 780 (70%) patients with stage I to III NSCLC who underwent surgical resection were randomly selected. The patients were subdivided into three groups: low BMI (<18.5 kg/m²), normal BMI (18.5 to <25.0 kg/m²), and high BMI (≥25.0 kg/m²). Cox proportional hazards regression analyses were performed to identify variables associated with survival.

RESULTS

In all patients, a low BMI was an independent prognostic factor for both DFS and OS (p=0.0175 and p=0.0134, respectively). In patients with stage I, a low BMI was also an independent prognostic factor for both DFS and OS (p=0.0066 and p<0.0001, respectively).

CONCLUSION

A low BMI was an independent prognostic factor after surgical resection of stage I NSCLC. Molecular targeted therapies, such as epidermal growth factor receptor inhibitors, anaplastic lymphoma kinase-tyrosine kinase inhibitors, and immune checkpoint inhibitors targeting the programmed cell death-1/programmed cell death-ligand 1 (PD-L1) pathway have greatly improved the clinical course for patients with non-small cell lung cancer (NSCLC), especially advanced-stage NSCLC (1-7). However, lung cancer remains the leading cause of cancer-related death worldwide (8). Even in patients with stage I to IIIA NSCLC, the clinical course is unsatisfactory despite the fact that surgical resection is the main treatment option (9). Therefore, it is important to identify useful, simple, and inexpensive prognostic markers in patients with resectable NSCLC.

A novel prognostic marker in patients with non-small cell lung cancer: musculo-immuno-nutritional score calculated by controlling nutritional status and creatine kinase

Background

Controlling nutritional status (CONUT) and skeletal muscle area (SMA) are both useful prognostic factors in patients with non-small cell lung cancer (NSCLC). We hypothesized that low serum creatine kinase (CK) would be a surrogate of decreased SMA, and defined a novel prognostic factor, CONUT/CK score (CNKS). The aim of this study was to elucidate the clinical significance of CNKS in NSCLC patients.

Methods

One hundred and eighty-nine patients who underwent surgical resection of NSCLC and whose preoperative computed tomography images were available were enrolled. The CNKS was calculated by summing CONUT score and CK score, which was defined as 0 if the CK concentration is within normal range, and 2 if it is under lower limit. The optimal cut-off values of CNKS and CONUT score were 4 and 2, respectively.

Results

Low CK was significantly associated with decreased SMA (P=0.012). The high CNKS group was significantly associated with men and smoking history (P=0.006 and P=0.015, respectively). The high CNKS group had significantly shorter overall survival (OS) and disease-free survival (DFS) (P<0.001 and P=0.003, respectively) than the low CNKS group. The CNKS was found to be an independent prognostic factor for OS and DFS (P=0.012 and P=0.017, respectively), while CONUT score was not. The CNKS was a novel significant predictor of a poor prognosis in patients with NSCLC.

Conclusions

The nutritional status combined with skeletal muscle index was suggested to provide more useful prognostic information than alone, which should be investigated in further prospective studies with a larger cohort.

HMGB1 blockade significantly improves luminal fibrous obliteration in a murine model of bronchiolitis obliterans syndrome

BACKGROUND

Although high-mobility group box-1 (HMGB1), which is a nuclear protein, was reported to enhance the allogeneic responses in transplantation, the effect of HMGB1 on bronchiolitis obliterans syndrome (BOS) is unknown.

METHODS

A murine heterotopic tracheal transplantation model was used. Protein concentrations of HMGB1, interferon-γ (IFN-γ), interleukin (IL)-10, and IL-17 were analyzed in the isografts, allografts, controls, and HMGB1-neutralizing antibody administered allografts (n = 6; Days 1, 3, 5, 7, 14, 21, and 28). The luminal fibrous occlusion was analyzed (n = 6; Days 7, 14, 21, and 28). Infiltrating CD8 and CD4 T lymphocytes around the allografts and serum levels of IFN-γ and IL-10 were evaluated (n = 6; Day 7).

RESULTS

The HMGB1 levels in the allografts were significantly increased compared with the isografts at Day 7. HMGB1 blockade did not change the IL-17 level, but decreased the IFN-γ/IL-10 ratio in the early phase (Days 5 and 7) and significantly improved the fibrous occlusion in the late phase (Days 14, 21, and 28). HMGB1 blockade significantly suppressed the CD8 T lymphocytes infiltration and decreased the serum IFN-γ/IL-10 ratio compared with the control at Day 7.

CONCLUSIONS

HMGB1 may be a trigger of the BOS pathogenesis and candidate target for the treatment of the disease.

Prognostic Impact of PD-L2 Expression and Association with PD-L1 in Patients with Small-cell Lung Cancer

BACKGROUND/AIM

Although some previous studies suggested that programmed cell death-ligand 1 (PD-L1) expression was significantly associated with a favorable postoperative prognosis in patients with small-cell lung cancer (SCLC), the prognostic significance of PD-L2 expression remains unknown. The aim of the current study was to investigate the prognostic significance of PD-L2 expression in patients with SCLC.

PATIENTS AND METHODS

Thirty-eight patients who underwent resection of SCLC were analyzed. A monoclonal anti-human PD-L1 antibody (clone SP142) and a monoclonal anti-human PD-L2 antibody (clone 176611) were used as the primary antibodies. Cut-off value for PD-L1 and PD-L2 expression was set to 1%.

RESULTS

Among 38 patients, 15 (39.5%) were positive for PD-L2 expression. No significant associations between PD-L2-positivity and clinicopathological factors, including PD-L1 positivity or prognosis were identified. No significant differences in disease-free survival and overall survival were observed between PD-L2-positive patients and PD-L2-negative patients (p=0.367 and p=0.726, respectively).

CONCLUSION

PD-L2 expression is not related to clinicopathological factors or postoperative prognosis in patients with SCLC, though this should be further investigated in studies involving larger populations.

Spotlight on lorlatinib and its potential in the treatment of NSCLC: the evidence to date

The identification of anaplastic lymphoma kinase (ALK), an oncogenetic driver mutation, in lung cancer has paved the way for a new era in the treatment of non-small cell lung cancer (NSCLC). Targeting ALK using tyrosine kinase inhibitors (TKI) has dramatically improved the prognosis of patients with ALK-rearranged NSCLC. However, most patients relapse on ALK-TKI therapy within a few years because of acquired resistance. One mechanism of acquiring resistance is a second mutation on the ALK gene, and the representative mutation is L1996M in the gatekeeper residue. In particular, the solvent-front ALK G1202R mutation is the common cause of resistance against first- and second-generation ALK-TKIs. Another major concern regarding ALK-TKI is metastasis to the central nervous system, commonly observed in patients relapsing after ALK-TKI therapy. The next-generation ALK inhibitor lorlatinib (PF-06463922) has therefore been developed to inhibit resistant ALK mutations, including ALK G1202R, and to penetrate the blood–brain barrier. In a Phase I/II trial, the safety and efficacy of lorlatinib were demonstrated in patients with advanced ALK-positive NSCLC, most of whom had central nervous system metastases and had previous ALK-TKI treatment. In this review, we discuss the structure, pharmacodynamics, and pharmacokinetics of lorlatinib and compare its characteristics with those of other ALK inhibitors. Furthermore, clinical trials for lorlatinib are summarized, and future perspectives in the management of patients with ALK-rearranged NSCLC are discussed.

Prevalence of Enhancer of Zeste Homolog 2 in Patients with Resected Small Cell Lung Cancer

BACKGROUND/AIM

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that is deeply involved in cancer pathogenesis. Although clinicopathological significance of EZH2 in non-small cell lung cancer has been gradually elucidated, such significance in small cell lung cancer (SCLC) has yet to be fully investigated.

PATIENTS AND METHODS

Forty patients with resected SCLC were analyzed for EZH2. EZH2 expression was evaluated using the Allred score (0-8) and was classified into negative (0-6) and positive (7 and 8). We evaluated the association between EZH2 and the clinicopathological characteristics and postoperative survivals.

RESULTS

Among 40 patients, 15 (37.5%) and 25 (62.5%) were classified as being negative and positive for EZH2, respectively. Fisher's exact test demonstrated no significant associations between the positivity for EZH2 and clinicopathological characteristics. No significant differences were observed in recurrence-free and overall survivals between EZH2-negative/low and EZH2-high patients.

CONCLUSION

EZH2 was frequently observed in patients with resected SCLC, but no significant associations were found between its expression and the clinicopathological characteristics and postoperative survivals.

The significant influence of having children on the postoperative prognosis of patients with nonsmall cell lung cancer: A propensity score-matched analysis

The aim of this study was to elucidate the relationship between family‐associated factors and the postoperative prognosis in patients with nonsmall cell lung cancer (NSCLC). Additionally, we investigated whether having children was associated with the postoperative maintenance of the nutritional status. We selected 438 NSCLC patients who had undergone curative lung resection between 2004 and 2011 at Kyushu University (Fukuoka, Japan), whose family‐associated factors were available. Nutritional indices, including the prognostic nutritional index (PNI), were used to estimate the change in the nutritional status for 1 year after surgery. A propensity score analysis was conducted after adjusting the following variables: sex, age, smoking history, performance status, pathological stage, and histological type. Three hundred patients (68.5%) had both children and partners. Forty‐nine patients (11.2%) only had children, and 56 (12.8%) patients only had a partner. Thirty‐three patients (7.5%) did not have a partner or children. The overall survival (OS) and disease‐free survival (DFS) of the partner‐present and partner‐absent patients did not differ to a statistically significant extent (P = .862 and P = .712, respectively). However, childless patients showed significantly shorter OS and DFS in comparison with patients with children (P = .005 and P = .002, respectively). The postoperative exacerbation of PNI was significantly greater in childless patients than in patients with children (P = .003). These results remained after propensity score matching. Childless patients had a significantly poorer postoperative prognosis than those with children. Surgeons caring for childless NSCLC patients should be aware of the poorer postoperative outcomes in this population.

Takotsubo Cardiomyopathy Developed After Two-stage Surgery for Double Primary Lung Cancer

Takotsubo cardiomyopathy (TC) is a syndrome characterized by transient local systolic dysfunction of the left ventricle with no evidence of coronary artery disease or acute plaque rupture. We present the case of 71-year-old woman who developed TC after two-stage surgery for double primary lung cancer. On computed tomography, lung nodules were identified in the left upper and right middle lobes. Based on the diagnosis of double primary lung cancer, we performed two-stage surgery (left upper lobectomy followed by right middle lobectomy). One day after the second surgery, respiratory failure developed. Electrocardiography showed ST segment elevation, serum troponin levels were elevated, and chest x-ray showed acute pulmonary edema. Cardiac catheterization showed no coronary artery disease and apical akinesia. Based on these findings, we diagnosed TC and the patient recovered with supportive treatment.

Significance of Spread Through Air Spaces in Resected Lung Adenocarcinomas With Lymph Node Metastasis

BACKGROUND

Spread through air spaces (STAS) is a recently recognized invasive pattern of lung cancer defined by the World Health Organization as micropapillary clusters, solid nests, or single cells spreading within air spaces beyond the edge of the main tumor. Although STAS has been shown to be a significant prognosticator for the postoperative survival in early-stage lung cancer treated with limited resection, its prognostic impact on the survival in completely resected adenocarcinomas with lymph node metastasis remains unclear.

PATIENTS AND METHODS

STAS was assessed in a total of 63 adenocarcinomas with lymph node metastasis in patients who underwent complete resection. STAS was defined as tumor cells within air spaces in the lung parenchyma beyond the edge of the main tumor. We evaluated the association between STAS and the clinicopathologic characteristics and the postoperative survival.

RESULTS

Among 63 patients, 31 (49.2%) and 32 (50.8%) had disease that was pathologically positive for N1 and N2, respectively. STAS was observed in 45 patients (73.0%) and was not significantly associated with any clinicopathologic characteristics. Patients with the STAS had significantly shorter recurrence-free survival (RFS) but not overall survival than those without STAS (P = .04 and P = .35, respectively). The 5-year RFS in patients with and without STAS was 25.1% and 56.7%, respectively. According to a multivariate analysis, positivity for STAS remained an independent prognostic parameter for RFS (hazard ratio = 3.09; 95% confidence interval, 1.47-7.16; P < .01).

CONCLUSION

STAS was predictive of a poor RFS in completely resected adenocarcinomas with lymph node metastasis.

High Frequency of Spread Through Air Spaces in Resected Small Cell Lung Cancer

BACKGROUND/AIM

Spread through air spaces (STAS) is a novel invasive pattern of lung cancer, especially adenocarcinoma and squamous cell carcinoma. However, its frequency and significance in patients with resected small cell lung cancer (SCLC) remains unclear.

PATIENTS AND METHODS

A total of 30 patients with resected SCLC were analyzed for STAS. STAS was classified as either no STAS, low STAS (1-4 single cells or clusters of STAS), or high STAS (≥5 single cells or clusters of STAS). We evaluated the association between STAS and clinicopathological characteristics and postoperative survivals.

RESULTS

Among 30 patients, 5 (17%), 6 (20%) and 19 (63%) were classified as having no, low and high STAS, respectively. Fisher's exact test demonstrated no significant associations between the positivity for STAS and clinicopathological characteristics. No significant differences were observed in recurrence-free and overall survival between STAS-negative/low and STAS-high patients.

CONCLUSION

STAS was frequently observed in patients with resected SCLC.

Safety of Simultaneous Bilateral Pulmonary Resection for Metastatic Lung Tumors

AIM

We investigated the safety of simultaneous bilateral lung resection for lung metastases.

PATIENTS AND METHODS

We retrospectively analyzed 185 patients with pulmonary metastases who underwent unilateral or bilateral pulmonary resection from August 2009 to December 2016 at a single institution.

RESULTS

Single-stage bilateral lung resection was undertaken in 19 patients, and the other 166 patients underwent unilateral pulmonary resection, including 20 patients who underwent repeated resections for synchronous or metachronous metastases. Operative time and drainage days in the bilateral group were significantly longer than those in the unilateral group (220±20 vs. 152±6.9 min: p<0.01, and 2.79±0.3 vs. 2.08±0.1 days: p<0.01). Incidence of postoperative complications and postoperative in-hospital days did not differ between the two groups (p=0.33 and 0.66, respectively). The bilateral group was further divided into two groups, namely, those who underwent wedge resection on both sides (WW) and those who underwent wedge resection on one side and segmentectomy or lobectomy on an opposite side (WSL). Operative time in the WSL group was significantly longer than that in the WW group (260±19 vs. 201±18 min: p=0.03). However, there was no significant difference in duration of chest tube use and postoperative hospital days between the two groups (p=0.26 and p=0.89). No severe postoperative complications occurred in either group.

CONCLUSION

One-stage bilateral pulmonary metastasectomy appears to be safe as long as only wedge resection is performed on at least one side.

The C-Reactive Protein/Albumin Ratio is a Novel Significant Prognostic Factor in Patients with Malignant Pleural Mesothelioma: A Retrospective Multi-institutional Study

BACKGROUND

Malignant pleural mesothelioma (MPM), a devastating neoplasm, is traditionally considered to be resistant to antitumor therapy. Identification of clinical prognostic indicators is therefore needed. Although the C-reactive protein/albumin ratio (CAR) has been used to predict the prognosis of many types of malignancy, its utility in patients with MPM is unknown.

METHODS

The data of 100 patients diagnosed as having MPM from 1995 to 2015 at the National Kyushu Cancer Center and Kyushu University were analyzed. The CAR was calculated as serum C-reactive protein concentration divided by albumin concentration. A cutoff for CAR was set at 0.58 according to a receiver operating characteristics curve for 1-year survival.

RESULTS

Thirty-five of the 100 (35.0%) patients were classified as having a high CAR. A high CAR was significantly associated with advanced clinical stage (p < 0.001) and chemotherapy alone (p = 0.002). Patients with a high CAR had significantly shorter overall survival (OS) (p < 0.001) and disease- or progression-free survival (DFS/PFS) (p < 0.001). These associations between CAR and prognosis remained significant after propensity score-matching. In multivariate analysis, a high CAR was an independent predictor of shorter OS and DFS/PFS (p = 0.003 and p = 0.008, respectively). Multivariate analyses of the subgroups of patients who had received chemotherapy and of patients who had undergone surgery also showed that a high CAR was an independent predictor of shorter OS and DFS/PFS.

CONCLUSIONS

CAR is an independent predictor of prognosis in MPM patients. This prognostic index contributes to clinicians' ability to predict benefit from treatment. Further larger, prospective studies are necessary to validate these findings.

Clinical Impact and Risk Factors for Skeletal Muscle Loss After Complete Resection of Early Non-small Cell Lung Cancer

BACKGROUND

A relationship between sarcopenia diagnosed by skeletal muscle area (SMA) and poor prognosis in cancer patients has recently been reported. This study aimed to clarify the clinical significance of postoperatively decreased SMA in patients with early non-small cell lung cancer (NSCLC).

METHODS

This study selected 101 patients with pathologic stage 1 NSCLC who had undergone pre- and postoperative (~ 1 year) computed tomography scans and lobectomy between 2005 and 2010 at Kyushu University Hospital. The post/pre ratio was defined as the postoperative normalized SMA (cm²/m²) at the 12th thoracic vertebra level divided by the preoperative normalized SMA. The cutoff value for the post/pre ratio was set at 0.9.

RESULTS

The study classified 31 patients (30.7%) as having decreased SMA. Poor performance status (PS) was significantly associated with decreased SMA (p = 0.048). The patients with decreased SMA had a significantly shorter disease-free survival (DFS) (p < 0.001) and overall survival (OS) (p < 0.001) than the other patients. Decreased SMA was found to be an independent prognostic factor for DFS (p = 0.010) and OS (p = 0.0072). The independent risk factors for skeletal muscle loss included poor PS (PS ≥ 1) and obstructive ventilatory impairment [forced expiratory volume (FEV) 1% < 70%].

CONCLUSIONS

Skeletal muscle loss after surgery is significantly associated with postoperative poor outcomes for patients with early NSCLC. Patients with poor PS, obstructive ventilatory impairment, or both need careful support to maintain their skeletal muscle mass. Future prospective studies may clarify whether physical activity and nutritional support improve postoperative prognosis.

Clinical Significance of PD-L1 Expression in Brain Metastases from Non-small Cell Lung Cancer

AIM

To investigate the association between positivity for programmed cell death-ligand 1 (PD-L1) in brain metastases (BM) and the prognosis or clinical factors in patients with non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Thirty-two patients with surgically resected brain-metastatic NSCLC were enrolled. The PD-L1 expression in BM was analyzed using the antibody against human PD-L1 (clone SP142). The PD-L1 positivity was defined as PD-L1 expression on brain-metastatic tumor cells of ≥5%.

RESULTS

Seven (21.9%) out of 32 patients showed PD-L1 positivity in BM. The PD-L1-positive BM group had a significantly shorter brain-specific disease-free survival than the PD-L1-negative BM group (p<0.05). PD-L1 positivity in BM was significantly associated with a heavy smoking history and the administration of radiotherapy for BM before surgery (p<0.05 and p<0.05, respectively).

CONCLUSION

The PD-L1 expression in BM from NSCLC may be associated with local recurrence following surgery, and the smoking- or radiotherapy-derived effects.

DXA-Rectified Appendicular Lean Mass: Development of Ultrasound Prediction Models in Older Adults

OBJECTIVE

Dual-energy X-ray absorptiometry (DXA)-derived appendicular lean soft tissue mass (aLM) is used to diagnose sarcopenia. However, DXA-derived aLM includes non-skeletal muscle components, such as fat-free component of adipose tissue fat cell. These components, if not accounted for, could falsely inflate the aLM in individuals with a high amount of adipose tissue mass. B-mode ultrasound accurately measures muscle size in older adults. We sought to develop regression-based prediction equations for estimating DXA-rectified appendicular lean tissue mass (i.e. DXA-derived aLM minus appendicular fat-free adipose tissue (aFFAT); abbreviated as aLM minus aFFAT) using B-mode ultrasound.

DESIGN

Cross-sectional study.

MEASUREMENTS

Three hundred and eighty-nine Japanese older adults (aged 60 to 79 years) volunteered in the study. aLM was measured using a DXA, and muscle thickness (MT) was measured using ultrasound at nine sites. An ordinary least-squares multiple linear regression model was used to predict aLM minus aFFAT from sex, age and varying muscle thicknesses multiplied by height. Based on previous studies, we chose to use 4 MT sites at the upper and lower extremities (4-site MT model) and a single site (1-site MT model) at the upper extremity to develop prediction models.

RESULTS

The linear prediction models (4 site MT model; R2 = 0.902, adjusted R2 = 0.899, and 1-site MT model; R2 = 0.868, adjusted R2 = 0.866) were found to be stable and accurate for estimating aLM minus aFFAT. Bootstrapping (n=1000) resulted in optimism values of 0.0062 (4-site MT model) and 0.0036 (1-site MT model).

CONCLUSION

The results indicated that ultrasound MT combined with height, age and sex can be used to accurately estimate aLM minus aFFAT in older Japanese adults. Newly developed ultrasound prediction equations to estimate aLM minus aFFAT may be a valuable tool in population-based studies to assess age-related rectified lean tissue mass loss.

Association Between PD-L1 Expression and Metabolic Activity on 18F-FDG PET/CT in Patients with Small-sized Lung Cancer

AIM

We evaluated the metabolic characteristics of small-sized lung cancer using ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT) with regard to programmed cell death ligand 1 (PD-L1) expression.

MATERIALS AND METHODS

PD-L1 expression was evaluated by immunohistochemistry with the antibody clone SP142 in 263 patients with surgically resected primary small-sized lung cancer. Specimens with <5% tumor membrane staining were considered negative. We examined the association between the frequency of PD-L1 expression and the maximum standardized uptake value (SUVmax) in preoperative ¹⁸F-FDG PET/CT.

RESULTS

Among patients with non-small cell lung cancer (NSCLC), the SUVmax was significantly higher in those with PD-L1 expression than in those without (p<0.0001). However, there was no correlation between SUVmax and PD-L1 expression in patients with neuroendocrine tumors (p=0.9638). Multivariate analysis revealed that smoking and a high SUVmax were independent predictors of PD-L1 expression.

CONCLUSION

PD-L1 expression was related to high glucose metabolism in small-sized NSCLC.

Relationship Between Preoperative Sarcopenia Status and Immuno-nutritional Parameters in Patients with Early-stage Non-small Cell Lung Cancer

BACKGROUND

Although the skeletal muscle in the region of the third lumbar vertebra (L3) is generally assessed in order to judge sarcopenia, not every patient with non-small cell lung cancer (NSCLC) undergoes computed tomography including the L3 region. We hypothesized that immuno-nutritional parameters could predict the existence of sarcopenia in patients with NSCLC.

AIM

The aim of this study was to retrospectively investigate the correlation between preoperative sarcopenia and immuno-nutritional parameters in patients with early-stage NSCLC.

PATIENTS AND METHODS

We selected 147 of patients with pathological stage I NSCLC who underwent preoperative measurement of immuno-nutritional parameters and CT including the L3 region.

RESULTS

Preoperative sarcopenia was significantly associated with female gender (p=0.0003) and poor prognosis (p=0.0322). In Kaplan-Meier analysis of overall survival (OS) by preoperative sarcopenia status, the sarcopenic group had significantly shorter OS than the non-sarcopenic group (5-year OS: 87.27% vs. 77.37%, p=0.0131, log-rank test). In multivariate analysis, the preoperative sarcopenia status (hazard ratio=5.138; 95% confidence interval=2.305-11.676; p<0.0001) was an independent prognostic factor. Preoperative sarcopenia status was significantly related to controlling nutritional status score (p=0.0071) and Geriatric Nutritional Risk Index (GNRI) (p<0.0001). Spearman's correlation test showed good significant correlation between preoperative sarcopenia status and GNRI (r=0.348, p<0.0001).

CONCLUSION

The preoperative GNRI is a simple and useful predictor for existence of preoperative sarcopenia which was associated with poor outcome in patients with early-stage NSCLC.

Successful resection of a tracheal metastasis of rectal cancer: a case report

A tracheal metastasis (TM) from non-pulmonary malignancy is extremely rare, and there are very few reports regarding TM. Here, we report a case of the successful tracheal resection of TM of colorectal cancer. A 36-year-old man underwent a surgical resection for the rectal cancer. Approximately 5 years after the surgical resection of the primary rectal cancer, an isolated TM was identified. The patient was successfully treated with a tracheal resection. In conclusion, the current case suggested that the best treatment of the isolated TM might be a surgical resection.

A Case of the Resected Lymphohistiocytoid Mesothelioma: BAP1 Is a Key of Accurate Diagnosis

BACKGROUND

Malignant mesothelioma (MM) is a well-known malignant tumor that occurs in the pleura and is histopathologically classified into three subtypes. Lymphohistiocytoid mesothelioma (LHM) is considered a variant of epithelioid MM, and few cases have been reported. First case of LHM was reported by Henderson et al. in 1988. It is difficult to precisely diagnose LHM, and it is often misdiagnosed as reactive mesothelial cell proliferation.

CASE REPORT

An 82-year-old man, with the smoking history of nine pack-years, was referred to our Department due to an abnormal shadow and pleural effusion in the left lung field on the chest X-ray imaging. His occupation was a teacher through his life without any asbestos exposure. Computed tomography (CT) and ¹⁸F-fluorodeoxyglucose-position emission tomography showed a tumor which was suggestive of malignancy on the left chest wall, with the possible invasion into the left 2nd to 4th ribs. He underwent a CT-guided biopsy and a thoracentesis, but the tumor was shown to be a benign tumor indicative of a reactive mesothelial cell proliferation. Then, he underwent a surgical resection and the tumor was suspected of liposarcoma macroscopically. Histological and immunohistochemical findings were suggestive of mesothelial lesion, such as nodular histiocytic or mesothelial hyperplasia. However, loss of BAP1 and no p16 homozygous deletion in the tumor cells led to the diagnosis of LHM, not a benign lesion.