Chihiro Konoeda

The ground glass opacity component can be eliminated from the T-factor assessment of lung adenocarcinoma †

OBJECTIVES The radiological ground glass opacity (GGO) component of an adenocarcinoma pathologically reflects a non-invasive adenocarcinoma in situ (AIS). Measuring the tumour diameter to include the GGO component may overestimate the T factor. In this retrospective study, we evaluated the effect of the GGO component on the recurrence of an adenocarcinoma. METHODS We reviewed patients who underwent a surgical resection of a lung adenocarcinoma and were pathologically proven to be T1-2N0M0, from 1999 to 2009. We conducted four different types of analyses (multivariate analysis, receiver operating characteristic [ROC] analysis, survival analysis according to subcategories and survival analysis of propensity score-matched pairs) to evaluate the impacts of GGO and the solid component on recurrence. RESULTS The study included 241 patients, and there were 34 recurrences. Sixty-eight cases with AIS and minimally invasive adenocarcinoma exhibited 100% recurrence-free survival. A univariate and a multivariate analysis revealed that the maximum tumour diameter measured in the mediastinal window was a better prognostic factor than the maximum tumour diameter in the lung window. This finding was supported by an ROC curve analysis, a subgroup analysis and a propensity score-matched analysis. An ROC curve analysis revealed that GGO component exclusion resulted in improved prognostic performance for recurrence and pathological vessel invasion. A subgroup analysis and a propensity score-matched analysis demonstrated that tumours with similar solid component sizes and different GGO sizes exhibited equivalent recurrence-free survival. CONCLUSIONS The GGO component showed little influence on recurrence. Recurrence-free survival was solely dependent on the solid component size. A T factor measured by the solid component may be a more accurate prognostic parameter.

Survival after extended thymectomy for thymoma.

OBJECTIVES Thymoma is a relatively rare tumour and is uniquely associated with autoimmune diseases such as myasthenia gravis (MG). However, the factors involved in the prognosis of thymoma remain under discussion. METHODS We retrospectively reviewed 162 patients who underwent extended thymectomy via median sternotomy for thymoma at our institute from 1976 to 2009. The histological subtype was classified according to the World Health Organization (WHO) histological classification system. Survival analysis was performed using the Kaplan-Meier method and the Cox proportional hazards model. RESULTS Tumours comprised 7 Type A tumours, 38 Type AB, 49 Type B1, 45 Type B2 and 23 Type B3. Various types of autoimmune diseases were comorbid in 66 patients. The median follow-up period was 94 months, and 14 patients experienced recurrence. Seven patients died of recurrent tumour, and 18 patients died of causes other than thymoma. The 10-year overall survival was 85.7%, and the 10-year disease-free survival (DFS) was 76.8%. The 10-year DFS was 62.5% for Type A, 86.3% for Type AB, 91.5% for Type B1, 77.1% for Type B2 and 26.3% for Type B3. In multivariate analysis, age, Type B3 and MG were determined as prognostic factors for survival. On the other hand, Masaokas stage did not influence survival. CONCLUSIONS Type B3 classified by the WHO histological classification system is a poor prognostic factor for survival of thymoma after extended thymectomy. Association with MG is possibly an indicator of poor survival. Age is an independent prognostic factor, suggesting favourable prognosis of thymoma after surgical treatment. Considering thymoma is a rare tumour, it would be necessary to build a multi-institutional database as soon as possible.

Significance of the Glasgow Prognostic Score as a prognostic indicator for lung cancer surgery.

OBJECTIVES The Glasgow Prognostic Score (GPS), which is calculated with C-reactive protein (CRP) and albumin (Alb) values, is a prognostic indicator for various types of cancers. However, its role in lung cancer still remains unclear, and its optimal cut-off values are controversial. Here, we evaluated the significance of the GPS and adjusted GPS (a-GPS) using our institutions cut-off values in patients undergoing resection for primary lung cancer. METHODS We analysed 1043 lung cancer patients who underwent resection between 1998 and 2012. The overall survival (OS) probabilities of the GPS subgroups were estimated using the Kaplan-Meier method and were compared using the log-rank test. The prognostic significance of the GPS and the a-GPS was assessed by the Cox proportional hazards model with clinicopathological variables and inflammation markers, such as the neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR). The GPS was calculated based on cut-off values of 1.0 mg/dl for CRP and 3.5 g/dl for Alb, as previously reported. The a-GPS was calculated based on cut-off values 0.3 mg/dl for CRP and 3.9 g/dl for Alb, which are the standard thresholds used by our institution. RESULTS The GPS and the a-GPS were correlated with preoperative factors, such as age, sex, smoking status, the NLR and the PLR, and oncological factors, including the pathological stage, histological type and level of lymphovascular invasion. The 5-year OS rates were 82, 55 and 55% with GPS 0, 1 and 2 (1 vs 0: P < 0.01; 2 vs 1: P = 0.66), respectively, and 88, 67 and 59% with a-GPS 0, 1 and 2 (1 vs 0: P < 0.01; 2 vs 1: P = 0.04), respectively. Multivariable analysis revealed that the GPS [1 vs 0, hazard ratio (HR): 1.63, 2 vs 0, HR: 1.44] and the a-GPS (1 vs 0, HR: 2.00, 2 vs 0, HR: 2.10) were independent prognostic factors. The a-GPS classification showed a clearer prognostic distribution than the GPS classification. CONCLUSIONS The GPS is a useful prognostic indicator of the OS in lung cancer surgery. The optimal cut-off values for GPS estimation may need to be re-evaluated.

Epithelial to Mesenchymal Transition in Murine Tracheal Allotransplantation: An Immunohistochemical Observation

BACKGROUND Aberrant epithelial repair is a crucial event in the airway remodeling that characterizes obliterative bronchiolitis (OB) in transplanted lungs. Recent data from experiments using epithelial cell lines and human airway tissues from lung transplant recipients suggest that epithelial to mesenchymal transition (EMT) plays an important role in OB. The aim of this study was to clarify whether EMT is involved in airway remodeling in an animal model. METHODS We performed orthotopic tracheal transplantation from BALB/c to C57BL/6 mice with from BALC/c to BALB/c mouse grafts as controls. Five allogeneic and 3 syngeneic recipients were humanely killed at predetermined postoperative days 2-12 as well as 14 and 21. Histology was evaluated using hematoxylin-eosin (H&E) staining. We studied the expression of specific markers, including E-cadherin, an epithelial marker; α-smooth muscle actin (SMA), and S100A4, mesenchymal markers, and zinc finger E-box-binding homeobox 1 (ZEB1), an EMT-related transcription factor. RESULTS Histologic assessment of serial H&E stains of allogeneic grafts showed remarkable pseudostratified respiratory epithelium with subepithelial inflammatory cell infiltration, as well as denuded and flattened epithelium and subepithelial fibrosis. The dynamic epithelial changes occurred earlier than the subepithelial fibrosis. Immunohistochemical evaluation indicated the emergence of α-SMA- positive epithelial cells that were most prominent on day 7. The expression of E-cadherin was attenuated in α-SMA-positive epithelial cells. S100A4 was also expressed in epithelial cells. A few days before the intraepithelial expression of α-SMA, ZEB1 emerged in the nuclei of epithelial cells. CONCLUSIONS We observed expression of an EMT-related transcription factor and mesenchymal markers along with the attenuation of epithelial marker expression in epithelial cells, several days before prominent subepithelial fibrosis formation, results that suggest epithelial cells to play an important fibrosis role in airway remodeling during epithelial to mesenchymal transition.

Prognostic impact of the current Japanese nodal classification on outcomes in resected non-small cell lung cancer.

BACKGROUND The prognosis of N2 non-small cell lung cancer (NSCLC) has been reported to be heterogeneous. The recently revised Japanese nodal classification subcategorizes N2 disease according to the tumor-bearing lobe. We evaluated the prognostic impact of the Japanese nodal classification and its ability to define favorable N2 disease in resected NSCLC. METHODS A total of 496 patients with NSCLC who underwent lobectomy with systematic lymph node dissection between 1998 and 2009 were analyzed retrospectively. N2 status was subdivided into N2a-1 and N2a-2, according to the Japanese nodal classification. Overall survival (OS), disease-free survival (DFS), and clinicopathologic features were compared between the two groups. RESULTS There were 67 cases with N2 disease. The outcome of resected N2a-2 NSCLC was far poorer than that of the N2a-1 group (5-year OS, 28% vs 62%, P < .001; 5-year DFS, 5% vs 35%, P < .001). Multivariate analysis revealed that pathologic N2a-2 was an independent prognostic factor (hazard ratio, 2.86; P < .05). Patients in the N2a-2 group showed more involved nodes and stations, less skip metastasis, and more locoregional recurrence than did patients in the N2a-1 group. The outcome of the N2a-1 group was satisfactory, and there was no significant difference in OS and DFS between N1 and N2a-1. CONCLUSIONS The Japanese nodal classification is able to identify a favorable N2 subgroup in resected NSCLC. Nodal staging by the Japanese system should be considered when a clinical trial of N2 disease is designed.

Fibroblasts of recipient origin contribute to airway fibrosis in murine tracheal transplantations

Dear Sirs, Bronchiolitis obliterans (BO) is a major limitation in the long-term success of lung transplantation. BO is characterized as fibrotic obliterations in small airways [1]. Fibroblasts are the key players in fibrosis. They produce extracellular matrix components, and those deposition results in fibrosis. The source of fibroblasts in transplanted organs is an unresolved question. Determining the origin of airway fibroblasts is considered to be a key step in establishing ways to prevent fibrosis. According to previous reports [2–4], three possible sources of fibroblasts in transplanted organs are recipient bone marrow cells [2], regional fibroblasts in the grafts [3], or transitioned donor cells that had undergone epithelial to mesenchymal transition (EMT) [4]. In this study, we investigated whether fibroblasts in rejected airways originated from donor or recipient cells using orthotopic tracheal transplantation (OTT) and heterotopic tracheal transplantation (HTT) mouse models with transgenic C57Bl/6 mice that ubiquitously expressed green fluorescent protein (GFP) (B6-Tg(GFP)). Subepithelial fibrosis in OTT allografts [5] and intraluminal fibrosis in HTT allografts [6] are observed on or after the 28th day. All animals received humane care in compliance with the ‘Guide for Animal Experimentation, University of Tokyo, revised 2007’ and the ‘Act on Welfare and Management of Animals’ published by Japanese ministry. All of the mice were purchased from Japan SLC, Inc. BALB/c and B6-Tg(GFP) female mice were used as donors or recipients. The heterotopic and orthotopic tracheal transplantations were performed under the operating microscope as previously reported [5,6]. For HTT, the donor tracheas were placed into the subcutaneous space of the anterior neck area. For OTTs and HTTs, the following strain combinations were used: transplantations from BALB/c to B6-Tg(GFP) mice, those from B6-Tg(GFP) to BALB/c mice, and from BALB/c to BALB/c as a syngeneic control. All grafts harvested on the 28th day were frozen within an optimal cutting temperature compound (Sakura Finetek Japan, Tokyo, Japan). The hematoxylin and eosin (H&E) stains were performed regularly after formalin fixation. Fibroblasts in allografts were characterized using anti-mouse a-SMA Cy3-conjugated antibody (C6198; Sigma-Aldrich, St. Louis, MO, USA). The emergence of fibroblasts suggested the occurrence of fibrosis. For GFP staining, an anti-mouse GFP fluorescein isothiocyanate-labeled antibody (A21311; Life technologies, Carlsbad, CA, USA) was used. After fixation and blocking, the sections were incubated with diluted conjugated antibodies (a-SMA 1:200, GFP 1:200). Additionally, DAPI (D1306; Life technologies, Carlsbad, CA, USA) was used as a nuclear counterstain. The images were acquired using a microscope (BIOREVO-9000; Keyence, Osaka, Japan). The percentages (GFP co-localized area)/ (subepithelial or intraluminal a-SMA expression area) were calculated using Image J Software (version 1.4.3.67; National Institute of Health, USA) for the OTTs and HTTs. The results are displayed as a box plot that was created with SPSS 11.0 (Dr. SPSS II for Windows, standard version; SPSS Inc., Chicago, IL, USA). In both OTT groups, subepithelial thickening and the emergence of fibroblasts occurred on the 28th day, and the reproducibility was similar in each group. For transplanted group from BALB/c to B6-Tg(GFP), the subepithelial a-SMA-positive cells were also GFP positive (Fig. 1a). In contrast, the subepithelial a-SMA-positive cells were GFP negative for the group transplanted from B6-Tg(GFP) to BALB/c (Fig. 1b). The proportion of GFP co-localization with the subepithelial aSMA staining is shown in Fig. 1e. Partial luminal obliterations were observed in both HTT groups on the 28th day. For transplanted group from BALB/c to B6-Tg(GFP), the majority of the a-SMA-positive cells in the graft lumens were GFP positive (Fig. 1c). In contrast, another allogeneic group, the luminal a-SMApositive fibroblasts were GFP negative (Fig. 1d). The calculated colocalized percentages for the luminal fibrosis groups Presented at the 33rd Annual meeting of the International Society for Heart and Lung Transplantation, Montr eal, 23–27 April 2013.

Toll-like Receptor 4 Signaling Affects Myofibroblasts Expression in Mice Tracheal Allograft

Toll-like Receptor 4 Signaling Affects Myofibroblasts Expression in Mice Tracheal Allograft M. Kawashima1, M. Sato1, T. Murakawa2, M. Anraku1, C. Konoeda1, A. Hosoi3, K. Kakimi3, J. Nakajima1. 1Department of Thoracic Surgery, The University of Tokyo, Tokyo, Japan, 2Department of Thoracic Surgery, Kansai Medical University, Osaka, Japan, 3Department of Immunotherapeutics, The University of Tokyo, Tokyo, Japan,