Balance of the prooxidant and antioxidant system is associated with mortality in critically ill patients

It is well known that oxidative stress causes certain diseases and organ damage. However, roles of oxidative stress in the acute phase of critical patients remain to be elucidated. This study aimed to investigate the balance of oxidative and antioxidative system and to clarify the association between oxidative stress and mortality in critically ill patients. This cohort study enrolled 247 patients transported to our emergency department by ambulance. Blood was drawn on hospital arrival, and serum derivatives of reactive oxidant metabolites (dROMs, oxidative index) and biological antioxidant potential (BAP, antioxidative index) were measured. Modified ratio (MR) is also calculated as BAP/dROMs/7.51. There were 197 survivors and 50 non-survivors. In the non-survivors, dROMs were significantly lower (274 vs 311, p<0.01), BAP was significantly higher (2,853 vs 2,138, p<0.01), and MR was significantly higher (1.51 vs 0.92, p<0.01) compared to those in the survivors. The AUC of MR was similar to that for the APACHE II score. Contrary to our expectations, higher BAP and lower dROMs were observed on admission in non-survivors. This may suggest that the antioxidative system is more dominant in the acute phase of severe insults and that the balance toward a higher antioxidative system is associated with mortality.

Timing of Mesenchymal Stromal Cell Therapy Defines its Immunosuppressive Effects in a Rat Lung Transplantation Model

Cell therapy using mesenchymal stromal cells (MSCs) is being studied for its immunosuppressive effects. In organ transplantation, the amount of MSCs that accumulate in transplanted organs and other organs may differ depending on administration timing, which may impact their immunosuppressive effects. In vitro, adipose-derived mesenchymal stem cells (ADMSCs) suppress lymphocyte activation under cell-to-cell contact conditions. However, in vivo, it is controversial whether ADMSCs are more effective in accumulating in transplanted organs or in secondary lymphoid organs. Herein, we aimed to investigate whether the timing of ADMSC administration affects its immunosuppression ability in a rat lung transplantation model. In the transplantation study, rats were intramuscularly administered half the usual dose of tacrolimus (0.5 mg/kg) every 24 h after lung transplantation. ADMSCs (1 × 106) were administered via the jugular vein before (PreTx) or after (PostTx) transplantation. Cell tracking using quantum dots was performed. ADMSCs accumulated predominantly in the lung and liver; fewer ADMSCs were distributed in the grafted lung in the PreTx group than in the PostTx group. The rejection rate was remarkably low in the ADMSC-administered groups, particularly in the PostTx group. Serum tumor necrosis factor-α (TNF-α), interferon-γ, and interleukin (IL)-6 levels showed a greater tendency to decrease in the PreTx group than in the PostTx group. The proportion of regulatory T cells in the grafted lung 10 days after transplantation was higher in the PostTx group than in the PreTx group. PostTx administration suppresses rejection better than PreTx administration, possibly due to regulatory T cell induction by ADMSCs accumulated in the transplanted lungs, suggesting a mechanism different from that in heart or kidney transplantation that PreTx administration is more effective than PostTx administration. These results could help establish cell therapy using MSCs in lung transplantation.

Donor and Recipient Adipose-Derived Mesenchymal Stem Cell Therapy for Rat Lung Transplantation

BACKGROUND

Mesenchymal stem cells (MSCs) are beginning to be proven as immunosuppressant in the field of organ transplantation. However, the effects of MSC origin (donor or recipient) on immunosuppression are not clear. Hence, we investigated the effects of recipient and donor adipose-derived MSCs (ADMSCs) on immunosuppression in a rat lung transplantation model.

METHODS

Subjects were divided into no treatment, tacrolimus administration, recipient ADMSC administration, donor ADMSC administration, and mixed donor and recipient ADMSC administration groups. ADMSC-administered groups were also treated with tacrolimus. Histologic study, immunofluorescence, immunohistochemistry, enzyme-linked immunosorbent assay, and polymerase chain reaction were used for various analyses.

RESULTS

Fluorescently labeled ADMSCs were predominant in the grafted donor lung, but not in the recipient lung, on day 5. On day 7, the pathologic rejection grades of the grafted donor lung were significantly lower in the ADMSC-administered groups (P < .05) and did not differ among these groups. Although serum hepatocyte growth factor and vascular endothelial growth factor levels did not differ among the groups, interleukin 10 level was slightly higher in the ADMSC-administered groups. The numbers of infiltrating regulatory T cells in the grafted lung were significantly higher in the ADMSC-administered groups (P < .05) but did not differ with cell origin. Transcriptional analysis suggested interleukin 6 suppression to be the main overlapping immunosuppressive mechanism, regardless of origin. Therefore, a donor or recipient origin may not influence the immunosuppressive efficacy of ADMSCs in our rat lung transplantation model.

CONCLUSIONS

Collectively, the results indicate that allogenic ADMSCs, regardless of their origin, may exert similar immunosuppressive effects in clinical organ transplantation.

Anticancer agent α-sulfoquinovosyl-acylpropanediol enhances the radiosensitivity of human malignant mesothelioma in nude mouse models

Malignant pleural mesothelioma (MPM) is a highly malignant disease that develops after asbestos exposure. Although the number of MPM cases is predicted to increase, no effective standard therapies have been established. The novel radiosensitizer α-sulfoquinovosyl-acylpropanediol (SQAP) enhances the effects of γ-radiation in human lung and prostate cancer cell lines and in animal models. In this study, we explored the radiosensitizing effect of SQAP and its mechanisms in MPM. The human MPM cell lines MSTO-211H and MESO-4 were implanted subcutaneously into the backs and thoracic cavities of immunodeficient KSN/Slc mice, then 2 mg/kg SQAP was intravenously administered with or without irradiation with a total body dose of 8 Gy. In both the orthotopic and ectopic xenograft murine models, the combination of irradiation plus SQAP delayed the implanted human MSTO-211H tumor growth. The analysis of the changes in the relative tumor volume of the MSTO-211H indicated a statistically significant difference after 8 Gy total body combined with 2 mg/kg SQAP, compared to both the untreated control (P = 0.0127) and the radiation treatment alone (P = 0.0171). After the treatment in each case, immunostaining of the harvested tumors revealed decreased cell proliferation, increased apoptosis and normalization of tumor blood vessels in the SQAP- and irradiation-treated group. Furthermore, hypoxia-inducible factor (HIF) 1 mRNA and protein expression were decreased, indicating reoxygenation in this group. In conclusion, SQAP improved hypoxic conditions in tumor tissue and may elicit a radiosensitizing effect in malignant mesothelioma models.

Outcomes of lung transplantation for idiopathic pleuroparenchymal fibroelastosis

PURPOSE

This study was performed to compare the outcome of lung transplantation (LT) for idiopathic pleuroparenchymal fibroelastosis (IPPFE) with that of LT for idiopathic pulmonary fibrosis (IPF).

METHODS

We reviewed, retrospectively, all adult patients who underwent LT for IPPFE or IPF in Japan between 1998 and 2018.

RESULTS

There were 100 patients eligible for this study (31 with IPPFE and 69 with IPF). Patients with IPPFE tended to have a significantly lower body mass index (BMI) than those with IPF (median, 16.7 vs. 22.6 kg/m², respectively; P < 0.01). However, Kaplan-Meier survival curves showed no significant difference in overall survival between the groups. The BMI did not increase in patients with IPPFE, even 1 year after LT (pretransplant, 16.5 ± 3.2 kg/m² vs. 1 year post-transplant, 15.6 ± 2.5 kg/m²; P = 0.08). The percent predicted forced vital capacity (%FVC) 1 year after LT was significantly lower in the IPPFE group than in the IPF group (48.4% ± 19.5% vs. 68.6% ± 15.5%, respectively; P < 0.01).

CONCLUSIONS

Despite extrapulmonary problems such as a flat chest, low BMI, and associated restrictive impairment persisting in patients with IPPFE, patient survival after LT for IPPFE or IPF was equivalent.

Enhanced airway stenting using a preoperative, three-dimensionally printed airway model simulation

Three-dimensionally printed organ models that facilitate preoperative simulations have the potential to improve outcomes of surgical procedures. Here, we report a case involving a 54-year-old man diagnosed with lung cancer of the right upper bronchus that was invading the right main bronchus. A right upper lobectomy with carinoplasty was performed. Although complete excision of the tumor was achieved, exertional dyspnea redeveloped 4 months post-surgery. Chest computed tomography revealed that airway stenosis caused by granulation had deformed the airway. Ablation of the granulation and airway stenting was required to improve the patient's symptoms. Prior to performing airway stenting, a three-dimensionally printed airway model was constructed, and the Y-shaped silicone stent used was modified in accordance with the model. After stenting, both the right and left bronchi were preserved, and the patient's symptoms improved. The three-dimensional printed airway model enhanced the accuracy and safety of the airway stenting procedure performed.

Lung Microvascular Niche, Repair, and Engineering

Biomaterials have been used for a long time in the field of medicine. Since the success of "tissue engineering" pioneered by Langer and Vacanti in 1993, tissue engineering studies have advanced from simple tissue generation to whole organ generation with three-dimensional reconstruction. Decellularized scaffolds have been widely used in the field of reconstructive surgery because the tissues used to generate decellularized scaffolds can be easily harvested from animals or humans. When a patient's own cells can be seeded onto decellularized biomaterials, theoretically this will create immunocompatible organs generated from allo- or xeno-organs. The most important aspect of lung tissue engineering is that the delicate three-dimensional structure of the organ is maintained during the tissue engineering process. Therefore, organ decellularization has special advantages for lung tissue engineering where it is essential to maintain the extremely thin basement membrane in the alveoli. Since 2010, there have been many methodological developments in the decellularization and recellularization of lung scaffolds, which includes improvements in the decellularization protocols and the selection and preparation of seeding cells. However, early transplanted engineered lungs terminated in organ failure in a short period. Immature vasculature reconstruction is considered to be the main cause of engineered organ failure. Immature vasculature causes thrombus formation in the engineered lung. Successful reconstruction of a mature vasculature network would be a major breakthrough in achieving success in lung engineering. In order to regenerate the mature vasculature network, we need to remodel the vascular niche, especially the microvasculature, in the organ scaffold. This review highlights the reconstruction of the vascular niche in a decellularized lung scaffold. Because the vascular niche consists of endothelial cells (ECs), pericytes, extracellular matrix (ECM), and the epithelial-endothelial interface, all of which might affect the vascular tight junction (TJ), we discuss ECM composition and reconstruction, the contribution of ECs and perivascular cells, the air-blood barrier (ABB) function, and the effects of physiological factors during the lung microvasculature repair and engineering process. The goal of the present review is to confirm the possibility of success in lung microvascular engineering in whole organ engineering and explore the future direction of the current methodology.

Human lung microvascular endothelial cells as potential alternatives to human umbilical vein endothelial cells in bio-3D-printed trachea-like structures

BACKGROUND

We have been trying to produce scaffold-free structures for airway regeneration using a bio-3D-printer with spheroids, to avoid scaffold-associated risks such as infection. Previous studies have shown that human umbilical vein endothelial cells (HUVECs) play an important role in such structures, but HUVECs cannot be isolated from adult humans. The aim of this study was to identify alternatives to HUVECs for use in scaffold-free structures.

METHODS

Three types of structure were compared, made of chondrocytes and mesenchymal stem cells with HUVECs, human lung microvascular endothelial cells (HMVEC-Ls), and induced pluripotent stem cell (iPSC)-derived endothelial cells.

RESULTS

No significant difference in tensile strength was observed between the three groups. Histologically, some small capillary-like tube formations comprising CD31-positive cells were observed in all groups. The number and diameters of such formations were significantly lower in the iPSC-derived endothelial cell group than in other groups. Glycosaminoglycan content was significantly lower in the iPSC-derived endothelial cell group than in the HUVEC group, while no significant difference was observed between the HUVEC and HMVEC-L groups.

CONCLUSIONS

HMVEC-Ls can replace HUVECs as a cell source for scaffold-free trachea-like structures. However, some limitations were associated with iPSC-derived endothelial cells.

A case of emergent operation for a life-threatening infectious mediastinal cyst

PURPOSE

Congenital mediastinal cysts are an uncommon but important diagnostic group. Most of these cysts are benign and asymptomatic in adults. However, some of them are clinically problematic due to the compression of neighboring organs, infection, or perforation.

CASE PRESENTATION

A 20-year-old man presented with severe dyspnea. Imaging revealed a mediastinal cyst in the subcarinal space compressing his right pulmonary artery and airway, which was later diagnosed as a bronchogenic cyst. Due to quick symptom exacerbation, emergent cyst wall fenestration was performed through video-assisted thoracic surgery with "stand-by" extracorporeal membrane oxygenation. Complete cyst resection was difficult owing to adhesion of the cyst to the surrounding organs. The symptoms immediately resolved after surgery and the postoperative course was uneventful.

CONCLUSION

Mediastinal bronchogenic cysts with life-threatening complications are rarely reported in adults. However, this case was life-threatening due to airway and vascular compression; emergent surgical care should be considered in such cases.

Replacement of Rat Tracheas by Layered, Trachea-Like, Scaffold-Free Structures of Human Cells Using a Bio-3D Printing System

Current scaffold-based tissue engineering approaches are subject to several limitations, such as design inflexibility, poor cytocompatibility, toxicity, and post-transplant degradation. Thus, scaffold-free tissue-engineered structures can be a promising solution to overcome the issues associated with classical scaffold-based materials in clinical transplantation. The present study seeks to optimize the culture conditions and cell combinations used to generate scaffold-free structures using a Bio-3D printing system. Human cartilage cells, human fibroblasts, human umbilical vein endothelial cells, and human mesenchymal stem cells from bone marrow are aggregated into spheroids and placed into a Bio-3D printing system with dedicated needles positioned according to 3D configuration data, to develop scaffold-free trachea-like tubes. Culturing the Bio-3D-printed structures with proper flow of specific medium in a bioreactor facilitates the rearrangement and self-organization of cells, improving physical strength and tissue function. The Bio-3D-printed tissue forms small-diameter trachea-like tubes that are implanted into rats with the support of catheters. It is confirmed that the tubes are viable in vivo and that the tracheal epithelium and capillaries proliferate. This tissue-engineered, scaffold-free, tubular structure can represent a significant step toward clinical application of bioengineered organs.

Successful resection to treat idiopathic azygos vein aneurysm

Azygos vein aneurysm is a rare disease. Surgical resection is usually performed when it ruptures. To avoid the thromboembolism, procedures that do not touch or push the aneurysm are recommended. Herein, we report a case of idiopathic azygos vein aneurysm. A 56-year-old woman was admitted to the hospital for right lateral chest pain. Chest enhanced multi-detector CT revealed an azygos vein aneurysm in the posterior mediastinal space. No thrombus in the aneurysm was detected before surgery. Video-assisted thoracic surgery was performed to treat the aneurysm. The patient was discharged from the hospital 4 days after surgery. Video-assisted thoracic surgery was a good option to treat an azygos vein aneurysm, and an enhanced multi-detector CT was useful for performing surgery safely.

Adenocarcinoma arising from an enteric cyst of the posterior mediastinum

Mediastinal enteric cysts are rare congenital thoracic cysts. The majority of mediastinal enteric cysts occur in infants, while they are rare in adults. Although most of these cysts are benign, surgical resection is sometimes performed, and malignant changes found in enteric cysts are rare. A 52-year-old man was incidentally discovered to have a posterior mediastinal mass and we excised the mass thoracoscopically. Histopathological findings showed an enteric cyst with adenocarcinoma. Comparing the pathological and magnetic resonance imaging (MRI) findings, MRI would help to detect malignant changes in such cysts. Although malignant changes found in mediastinal enteric cysts are extremely rare, clinicians should always keep in mind that those cysts have malignant potential and careful evaluation of MRI would be a clue for surgical indication.

Is Pleurectomy/Decortication Superior to Extrapleural Pneumonectomy for Patients with Malignant Pleural Mesothelioma? A Single-Institutional Experience

PURPOSE

This study was performed to compare the outcome of pleurectomy/decortication (P/D) with that of extrapleural pneumonectomy (EPP) for patients with malignant pleural mesothelioma (MPM).

METHODS

Patients with MPM underwent either P/D or EPP from August 2008 to December 2014. Various clinicopathological factors were analyzed to identify differences between the two procedures.

RESULTS

P/D was performed in nine patients and EPP in 30 patients. Most of the patients' background characteristics were not significantly different between the groups. The surgery time (680 vs. 586 min, p = 0.0034) and bleeding volume (4050 vs. 2110 mL, p = 0.002) were significantly greater in P/D than in EPP; however, grade ≥3 complications (44% vs. 33%, p = 0.54) and length of postoperative hospital stay (29 vs. 37 days, p = 0.26) were not significantly different. The median survival time and 2- and 3-year survival rates in all patients were 16.7 months, 28.5%, and 15.3%, respectively. The median survival time and 2- and 3-year survival in the P/D and EPP groups were 22.5 months, 43.8%, and 43.8% and 16.5 months, 24.0%, and 14.4%, respectively (p = 0.13).

CONCLUSION

Survival of patients with MPM remains poor despite multidisciplinary treatment. P/D is comparable with EPP and could be a safe and another surgical treatment for patients with MPM.

Three-dimensional (3D) bronchial tree model for bronchial resection with pulmonary segmentectomy

There has been an increase in pulmonary segmentectomy procedures because of increased numbers of individuals with small lung cancer. However, it is difficult to identify the correct bronchus during surgery even with pre-operative three-dimensional (3D) computed tomography. We investigated using a 3D-printed model of the bronchi to prepare for bronchus resection during pulmonary segmentectomy. The model was useful to determine pre-operatively which bronchus should be transected, and being composed of a soft material it could be mobilized similarly to the actual bronchus during surgery. This simulation can increase surgeons' confidence to identify the correct bronchus during pulmonary segmentectomy.

Bioengineered lungs generated from human iPSCs-derived epithelial cells on native extracellular matrix

The development of an alternative source for donor lungs would change the paradigm of lung transplantation. Recent studies have demonstrated the potential feasibility of using decellularized lungs as scaffolds for lung tissue regeneration and subsequent implantation. However, finding a reliable cell source and the ability to scale up for recellularization of the lung scaffold still remain significant challenges. To explore the possibility of regeneration of human lung tissue from stem cells in vitro, populations of lung progenitor cells were generated from human iPSCs. To explore the feasibility of producing engineered lungs from stem cells, we repopulated decellularized human lung and rat lungs with iPSC-derived epithelial progenitor cells. The iPSCs-derived epithelial progenitor cells lined the decellularized human lung and expressed most of the epithelial markers when were cultured in a lung bioreactor system. In decellularized rat lungs, these human-derived cells attach and proliferate in a manner similar to what was observed in the decellularized human lung. Our results suggest that repopulation of lung matrix with iPSC-derived lung epithelial cells may be a viable strategy for human lung regeneration and represents an important early step toward translation of this technology.

Engineered Tissue-Stent Biocomposites as Tracheal Replacements

Here we report the creation of a novel tracheal construct in the form of an engineered, acellular tissue-stent biocomposite trachea (TSBT). Allogeneic or xenogeneic smooth muscle cells are cultured on polyglycolic acid polymer-metal stent scaffold leading to the formation of a tissue comprising cells, their deposited collagenous matrix, and the stent material. Thorough decellularization then produces a final acellular tubular construct. Engineered TSBTs were tested as end-to-end tracheal replacements in 11 rats and 3 nonhuman primates. Over a period of 8 weeks, no instances of airway perforation, infection, stent migration, or erosion were observed. Histological analyses reveal that the patent implants remodel adaptively with native host cells, including formation of connective tissue in the tracheal wall and formation of a confluent, columnar epithelium in the graft lumen, although some instances of airway stenosis were observed. Overall, TSBTs resisted collapse and compression that often limit the function of other decellularized tracheal replacements, and additionally do not require any cells from the intended recipient. Such engineered TSBTs represent a model for future efforts in tracheal regeneration.

Successful Resection of locally infiltrative Glomus Tumor without pulmonary resection

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Extracutaneous glomus tumors occurring in the bronchus is very rare.

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Two term resections enabled us to make an accurate diagnosis and evaluation.

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After bronchoscopic treatment, curative pulmonary resection was performed and preservation of lung function was successful.

Introduction

Extracutaneous glomus tumors occurring in the bronchus is very rare. Complete resection is basic procedure for treatment of glomus tumor. We present a glomus tumor of the left main bronchus that was successfully treated with rigid bronchoscopy followed by sleeve resection of the left main bronchus.

Presentation of case

A 56-year-old man underwent two term resections to glomus tumor that originated from the left main bronchus. Firstly, we performed palliative resection with rigid bronchoscopy to make the correct diagnosis and evaluate the extent of the tumor. We subsequently performed curative resection. No complications or recurrence has occurred since the operation took place one year ago.

Discussion

Before curative resection, it is important to confirm the diagnosis and spread of the tumor. Therefore, palliative tumor resection by rigid bronchoscopy was useful to make the correct diagnosis, evaluate the extent of the tumor and open the bronchial lumen. After bronchoscopic treatment, curative pulmonary resection was performed and preservation of lung function was successful.

Conclusion

Two term resections enabled us to make an accurate diagnosis and evaluation, thereby preserving respiratory function without pulmonary resection.

Single lung retrieval from a donor supported by a left ventricular assist device

The number of patients who need cardiac support with a left ventricular assist device (LVAD) has increased over the last decade. However, the number of reports of organ retrieval from donors with an LVAD is still small. Successful lung retrieval for single lung transplantation was performed from a donor on LVAD support. This required special care not to injure the heart, great vessels, and the device, particularly the outflow conduit, because of significant conglutination around the device. A right single lung transplantation was performed successfully, with no postoperative complications. This means that patients on an LVAD could be potential donors for lung transplantation.

Transplantation of bioengineered rat lungs recellularized with endothelial and adipose-derived stromal cells

Bioengineered lungs consisting of a decellularized lung scaffold that is repopulated with a patient's own cells could provide desperately needed donor organs in the future. This approach has been tested in rats, and has been partially explored in porcine and human lungs. However, existing bioengineered lungs are fragile, in part because of their immature vascular structure. Herein, we report the application of adipose-derived stem/stromal cells (ASCs) for engineering the pulmonary vasculature in a decellularized rat lung scaffold. We found that pre-seeded ASCs differentiated into pericytes and stabilized the endothelial cell (EC) monolayer in nascent pulmonary vessels, thereby contributing to EC survival in the regenerated lungs. The ASC-mediated stabilization of the ECs clearly reduced vascular permeability and suppressed alveolar hemorrhage in an orthotopic transplant model for up to 3 h after extubation. Fibroblast growth factor 9, a mesenchyme-targeting growth factor, enhanced ASC differentiation into pericytes but overstimulated their proliferation, causing a partial obstruction of the vasculature in the regenerated lung. ASCs may therefore provide a promising cell source for vascular regeneration in bioengineered lungs, though additional work is needed to optimize the growth factor or hormone milieu for organ culture.

Temporary bypass for superior vena cava reconstruction with Anthron bypass tubeTM

Total superior vena cava (SVC) clamping for SVC replacement or repair can be used in thoracic surgery. A bypass technique is an option to avoid hemodynamic instability and cerebral venous hypertension and hypoperfusion. The present report describes a venous bypass technique using Anthron bypass tube^TM for total SVC clamping. Indications for this procedure include the need for a temporary bypass between the brachiocephalic vein and atrium for complete tumor resection. This procedure allows the surgeons sufficient time to complete replacement of SVC or partial resection of SVC without adverse effects. Further, it is a relatively simple procedure requiring minimal time.

Avoiding completion pneumonectomy by omentopexy for bronchial dehiscence

A 56-year-old man underwent right upper sleeve lobectomy with mediastinal lymph node dissection after induction chemoradiotherapy (CRT) for advanced non-small cell lung cancer (NSCLC). The patient developed anastomotic dehiscence 11 days postoperatively. A fistula measuring 10 mm in diameter was found around the transition region between cartilage and membranous portions of the bronchus. To avoid completion right pneumonectomy, omentopexy was performed to cover the bronchial dehiscence and facilitate healing. The patient's condition improved after a redo operation with surveillance bronchoscopy to check the anastomotic status. Omentopexy may be a feasible treatment option for bronchial dehiscence and could help to avoid completion pneumonectomy (CP).

[Granuloma by Foreign Body Reaction to the Stapler Used for Partial Resection of the Lung]

A 66-year-old woman underwent right lower lobectomy and partial resection of the middle lobe for Stage I A double lung cancer. Five years after the operation, a routine computed tomography (CT) scan showed a mass on the staple line at the middle lobe. The mass was enlarged on CT scan after 6 months. A definitive diagnosis could not be made by bronchoscopic examination and fluoro-2-deoxy-glucose(FDG)/positron emission tomography( PET)-CT showed FDG uptake in the mass( early phase:SUVmax=3.24, late phase:SUVmax=4.31). Local recurrence of lung cancer was not completely denied, and right middle lobectomy was performed. Histopathologically, the resected specimen revealed granuloma with foreign body reaction. We should keep in mind the possibility of granuloma as differential diagnosis of lung cancer when using stapler.

Double stenting with silicone and metallic stents for malignant airway stenosis

For severe malignant airway stenosis, there are several types of commercially available airway stents, and each has its own advantages and disadvantages. We herein describe the safety and efficacy of combination stenting with silicone and metallic stents for patients with extended malignant airway stenosis. Seven patients with malignant airway stenosis were treated via combination stenting with a silicone stent and a metallic stent for extended airway stenosis from the central to peripheral airways. Five patients were diagnosed with advanced esophageal cancer, two of whom had tracheoesophageal fistulas. One patient had adenoid cystic carcinoma, and another had mediastinal tumor. There were no specific complications related to the double stenting. Combination stenting with silicone and metallic stents proved to be a safe option for patients with severe, extended, and complicated malignant airway stenosis.

Is early postoperative administration of pregabalin beneficial for patients with lung cancer?-randomized control trial

BACKGROUND

Post-thoracotomy pain is an obstacle for lung-cancer patients even after introduction of less invasive surgical procedures. The aim of this prospective study was to evaluate if early postoperative administration of pregabalin is beneficial for patients with non-small cell lung cancer (NSCLC).

METHODS

We conducted a randomized open control trial. Patients with NSCLC were allocated randomly to epidural and nonsteroidal anti-inflammatory drug (NSAID) use for analgesia (control group) or pregabalin use (pregabalin group). Primary endpoint was the frequency of additional administration of a NSAID. Secondary endpoints were intensity of ongoing pain, frequency of neuropathic pain, and pain catastrophizing.

RESULTS

Seventy-two patients were registered and allocated. Thirty-four cases in the control group and 33 in the pregabalin group were assessed. Age, sex, body mass index (BMI), type of surgical procedure, type of lymph-node dissection, operation time, bleeding, duration of chest-tube insertion, and postoperative hospital stay between the two groups was not significantly different. Frequency of additional NSAID use between the control group (2±4 suppositories) and pregabalin group (2±3 suppositories) was not significantly different (P=0.62). Numeric Rating Scale (NRS) for the intensity of ongoing pain, frequency of neuropathic pain, and Pain Catastrophizing Scale (PCS) between each group were not significantly different at any time until 3 months after surgery.

CONCLUSIONS

Early postoperative administration of pregabalin is not beneficial for patients with NSCLC.

Ratio of C-reactive protein to albumin is a prognostic factor for operable non-small-cell lung cancer in elderly patients

PURPOSE

The aim of this retrospective study was to evaluate inflammation-based scoring as a prognostic factor for operable non-small-cell lung cancer (NSCLC) in elderly patients.

METHODS

We collected preoperative data from 108 patients aged above 80 years with NSCLC. Inflammation-based scoring systems, including the C-reactive protein to albumin ratio (CAR) and the Glasgow prognostic score (GPS), as well as other clinicopathological factors, were evaluated as potential prognostic factors.

RESULTS

The median patient age was 82 (range 80-93) years and the 5-year overall and disease-specific survival rates were 49.7 and 73.9%, respectively. The cut-off value for CAR was calculated using a receiver operator characteristics analysis and patients were dichotomized accordingly. Patients with a low CAR had significantly higher overall survival than those with a high CAR (<0.028; 65.2% vs. ≥0.028; 31.0%, respectively; p < 0.01). In univariate analysis, female gender, a low Charlson comorbidity index of 0 or 1 and a low CAR were significantly identified in overall survival. On multivariate analysis, a low CAR (p = 0.03, hazard ratio: 2.13, 95% confidence interval 1.074-4.295) was identified as a significant prognostic factor.

CONCLUSIONS

The preoperative CAR is a useful predictor of overall survival and could be a simple prognostic tool to help identify resectable NSCLC in elderly patients.

[Anastomotic Airway Complications after Lung Transplantation]

Anastomotic airway complications still remain an important issue after lung transplantation. Most of the complications are stenosis and anastomotic leakage. Stent insertion is one option for the stenosis. We review the anastomotic airway complications and report our recent experience of stent insertion using 3-dimensional printed airway model.

Abstract 5028: Reverse translational research for identifying the correlation between EGFR mutation status and DPD protein expression in lung adenocarcinoma

[Background] Reverse translation research is often described as “From the Bedside to the Bench”, which means taking an understanding gained by observations in a patient population to create hypotheses and confirmation of the hypothesis in the laboratory. According to current chemotherapy treatment for lung adenocarcinoma, empirically, clinicians know that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKI) tend to be effective for radiological ground glass nodule- type lung adenocarcinomas. On the other hand, it has been shown that 5-FU sensitivity in patients with non-small cell lung cancer (NSCLC) is associated with EGFR mutation status. From such clinical hints, we identified a relationship between dihydropyrimidine dehydrogenase (DPD), a 5-FU degrading enzyme, and EGFR mutation status.

[Methods] We firstly focused on clinicopathologic factors and in vitro correlations between DPD expression and EGFR mutation status. Secondly, we analyzed crosstalk between the EGFR signal cascade and DPD protein expression using EGFR mutated and not mutated cell lines.

[Clinicopathological Study] EGFR mutations and messenger RNA (mRNA) levels of DPD were analyzed in 47 resected NSCLC tumors by laser-capture microdissection. EGFR mutation status and the immunohistochemical expression of DPD in 49 resected NSCLC tumors were also examined. As a result, adenocarcinoma in situ showed significantly higher DPD mRNA levels and more EGFR mutation frequency than other histological types (P &lt; 0.05). DPD immunopositive cases were more frequently observed in adenocarcinoma, in females, and in nonsmokers; which were correlated with EGFR mutation status (P &lt; 0.003).

[Basic Study] In vitro, EGFR-mutated cell lines (PC9, HCC827; exon19 E746-A750 and H1975; exon21 L858R, T790M, gefitinib resistant) showed higher DPD mRNA and protein expression than wild types (H1437, H1299). The DPD gene (DPYD), and DPD protein expression were known to be regulated by the transcription factor Sp1. In the PC9 study, EGF treatment induced up-regulation of both Sp1 and DPD. Gefitinib, an EGFR-TKI, and mithramycin A, specific Sp-1 inhibitors, suppressed them. However, the phenomena were not observed in EGFR-wild types and EGFR-TKI resistant cell lines. These results suggest DPD is regulated mainly in EGFR signal cascade enhanced lung cancers such as EGFR mutated adenocarcinomas. 5-FU and its derivatives such as uracil-tegafur (UFT) or S-1 might be effective for EGFR wild type adenocarcinomas because of the low DPD expression.

[Conclusion] Reverse translational research can provide useful information for clinical treatment. In the present study, we identified crosstalk between the EGFR signal cascade and DPD protein expression, which might affect therapeutic strategy for lung adenocarcinomas.

Citation Format: Tomoshi Tsuchiya, Tetsuo Tominaga, Koji Mochinaga, Naoya Yamasaki, Keitaro Matsumoto, Takuro Miyazaki, Go Hatachi, Yuka Kitajima, Takeshi Nagayasu. Reverse translational research for identifying the correlation between EGFR mutation status and DPD protein expression in lung adenocarcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5028.

Ventilation-Based Decellularization System of the Lung

The demand for donated organs greatly exceeds the availability. Alternatives to organ donation, such as laboratory-engineered organs, are therefore being developed. One approach is to decellularize the organ and reseed it with selected cells, ideally from the organ recipient. Organ decellularization has typically been attempted by the administration of detergents into vessels such as the portal vein in the liver. However, in the case of the lung, the airway provides another potential administration route, because it has a wide contact area between cells and detergents in the tracheal tree and alveoli. In the present study, we introduce a novel ventilation-based decellularization system for the lung and compare its efficacy to ordinary decellularization systems administering detergent through the pulmonary artery. Rat lungs were decellularized using 500 mL of 3-[(3-cholamidopropyl) dimethylammonio]-1-Propanesulfonate (CHAPS) decellularization solution administrated through the pulmonary artery (vessel group) or through the trachea (airway group). The vessel group was infused CHAPS solution using a gravitational pressure head of 20 cmH2O. The airway group was infused with the detergent using negative pressure and positive end-expiratory pressure, for a volume 10cc with each inspiration in a bioreactor. Pathological and immunohistochemical findings indicated that components of the extracellular matrix (ECM), including proteoglycans, elastic fibers, fibronectin, and laminin, were more decreased in the airway group than in the vessel group. Western blot analysis showed that MHC class I antigen and β-actin were not detected in both decellularized groups. A collagen assay showed that collagen was 70% preserved in both groups compared to native lung. Glycosaminoglycan (GAG) and DNA assays showed that GAG and DNA contents were strongly diminished in both decellularized groups, but those contents were smaller in the airway group than in the vessel group. Accordingly, the alveolar wall was thinner on electron microscopy, and DNA remnants were not observed in the airway group. Infusion of red blood cells indicated that capillary walls were preserved without blood leakage in both groups. In conclusion, we describe a novel approach for decellularization through the airway that represents a more stringent method for both DNA and ECM removal, with capillary wall preservation.

Down-Regulation of Nogo-B Expression as a Newly Identified Feature of Intrahepatic Cholangiocarcinoma

Nogo-B, located in the endoplasmic reticulum, is an isoform belonging to the reticulon protein family, which is expressed specifically in cholangiocytes and non-parenchymal cells in the liver. Nogo-B expression is down-regulated with the progression of liver fibrosis, but its distinct function in liver malignancies has not been fully clarified. We have hypothesized that Nogo-B expression may be altered in intrahepatic cholangiocarcinoma (ICC), a relatively rare type of primary liver cancer with highly malignant behavior. The present study aimed to investigate the relationship between Nogo-B expression, assessed by immunohistochemical staining, and clinicopathological factors and prognosis in 34 ICC patients. Positive expression was observed in 19 (56%) of 34 ICC specimens: 6 patients (18%) with positivity levels of 1+ (positive cells in 10-50% of cancer cells) and 13 patients (38%) with 2+ (positive cells over 50%). Importantly, the remaining 15 patients (44%) were categorized as negative expression (Nogo-B-positive cells, less than 10%). Conversely, the mass-forming type of ICC tended to express Nogo-B with the degree of 2+ positivity, compared to the periductal infiltration type (p = 0.064), and the mass-forming type showed a better 5-year survival rate (66% vs. 5%) after hepatectomy (p < 0.05). However, the degree of positivity was not associated with tumor relapse rate, disease-free and overall survival, although each of the periductal infiltration type, intrahepatic metastasis, larger tumor size, and lower microvessel counts was associated with lower survival rates. We propose that Nogo-B expression is down-regulated in ICC, the implication of which, however, remains to be investigated.

Management of unexpected intraoperative bleeding during thoracoscopic pulmonary resection: a single institutional experience

PURPOSE

Unexpected intraoperative bleeding during thoracoscopic surgery, necessitating emergency conversion to thoracotomy, is gradually being reported. We reviewed our experience of encountering unexpected bleeding during thoracoscopic surgery.

METHODS

We defined "unexpected intraoperative bleeding" as the need for hemostatic procedures with angiorrhaphy, with or without a sealant. The location, cause, and management of injured vessels, and perioperative outcomes were investigated and compared with those for patients without injured vessels.

RESULTS

Between 2007 and 2014, a total of 241 thoracoscopic anatomical pulmonary resections were performed at our hospital. Twenty (8.3 %) of these patients required hemostatic procedures with angiorrhaphy, with or without a sealant. The main injured vessels were the pulmonary artery (n = 13) and vein (n = 3) and the main causes of injury were related to technical issues with energy devices and staplers. There were no morbidities related to intraoperative bleeding. The operation time and blood loss were significantly greater in the patients with vessel injury than in those without vessel injury, but perioperative morbidities and the duration of chest tube insertion (4.5 vs. 3.5 days, average, p = 0.20) and postoperative hospital stay (12.7 vs. 11.0 days, average, p = 0.08) were not significantly different.

CONCLUSIONS

The frequency of unexpected bleeding was relatively high in this series, but its management and outcomes were satisfactory in terms of safety.

Click-coated, heparinized, decellularized vascular grafts

A novel method enabling the engineering of a dense and appropriately oriented heparin-containing layer on decellularized aortas has been developed. Amino groups of decellularized aortas were first modified to azido groups using 3-azidobenzoic acid. Azide-clickable dendrons were attached onto the azido groups through "alkyne-azide" click chemistry, affording a tenfold amplification of adhesions sites. Dendron end groups were finally decorated with end-on modified heparin chains. Heparin chains were oriented like heparan sulfate groups on native endothelial cells surface. X-ray photoelectron spectroscopy, nuclear magnetic resonance imaging, mass spectrometry and Fourier transform infrared FTIR spectroscopy were used to characterize the synthesis steps, building the final heparin layered coatings. The continuity of the heparin coating was verified using fluorescent microscopy and histological analysis. The efficacy of heparin linkage was demonstrated with factor Xa anti-thrombogenic assay and platelet adhesion studies. The results suggest that oriented heparin immobilization to decellularized aortas may improve the in vivo blood compatibility of decellularized aortas and vessels.

Recruitment of Young Medical Apprentices (RYOMA) project: a comprehensive surgical education program at a local academic institute in Japan

OBJECTIVES

The number of young surgeons in Japan has significantly decreased in recent years, which may lead to future problems in the medical field. Therefore, comprehensive training programs for young surgeons are needed.

DESIGN

Retrospective study

SETTING

We developed a specific education program called the "Recruitment of Young Medical Apprentices" (RYOMA) project.

PARTICIPANTS

We performed this project between January 2008 and August 2013 on fourth- to sixth-year medical students and internship doctors. The RYOMA project included step-by-step surgical education programs on open and scopic procedures as dry, wet, and animal laboratory training. Our goal was to increase the number of young and specialist surgeons.

RESULTS

Based on an interview questionnaire answered by 90 medical students, most young students were interested in surgical training and several chose to become surgeons in the future. The most positive opinions regarding the field of surgery were the impressive results achieved with surgery, whereas negative opinions included the difficulty of the surgical skill, physical concerns related to difficult work environments, and the severity of surgical procedures. The present program has begun to resolve negative opinions through adequate training or simulations. Of the 19 medical students and internship doctors who attended the RYOMA project in 2008, 17 trainees (90%) were satisfied with this special surgical program and 16 (88%) showed interest in becoming surgeons. The number of participants considering the field of surgery increased between 2008 and 2013. Of 23 participants, 19 (83%) had a positive opinion of the program after the training.

CONCLUSIONS

Gaining experience in surgical training from an early stage in medical school and step-by-step authorized education by teaching staff are important for recruiting students and increasing the number of young surgeons.

Clinical significances of cancer stem cells markers in patients with intrahepatic cholangiocarcinoma who underwent hepatectomy

The present study aimed to elucidate the relationship between cancer stem cells markers (CSCs), according to cell adhesion molecule (CD44) and glioma-associated oncogene homolog-1 (GLI1) expression, and clinicopathological factors and prognosis in 38 patients with intrahepatic cholangiocarcinoma (ICC) who underwent hepatectomy. CD44 and GLI1 expression was examined by immunohistochemical staining methods. The relationship with tumor angiogenesis or proliferation activity was also analyzed. Positivity of CD44 was 18% and that of GLI1 was 39%, but there was no significant correlation between the expressions of both. On macroscopic findings, CD44 expression in the periductal infiltration-type of ICC was significantly higher than in other types (p<0.01), and this type showed significantly worse survival after hepatectomy. Positive expression of GLI1 was significantly associated with older age. Although expression of neither CD44 nor GLI1 was significantly associated with disease-free survival, positive expression of both CD44 and GLI1 led to a significantly lower 3-year disease-free survival rate (0%; p<0.05). With respect to 5-year overall survival after hepatectomy, expression of both CD44 and GLI1 was not significantly associated with survival rate. CSCs might be useful markers for tumor-free survival in patients with ICC after hepatectomy and further investigation in larger series is warranted.

[Association between hemostasis/coagulation-system parameters and clinicopathological factors in patients with primary lung cancer]

Previous studies have gradually clarified the relationship between cancer and blood coagulation disorder and its mechanism. Various studies have also reported the association between lung cancer and coagulation disorder. However, it is rare to measure most hemostasis/coagulation-system test parameters in clinical practice. In this study, we investigated the association of hemostasis/coagulation-system test parameters, such as the prothrombin time (PT), activated partial thromboplastin time (APTT), bleeding time, and platelet count, which are routinely measured as preoperative examination parameters in patients with lung cancer, with the histopathologically evaluated stage of lung cancer. Although the mean values of hemostasis/coagulation-system parameters in all subjects were within the normal ranges, there were significant changes with respect to the clinico-pathological factors, showing a specific tendency. In patients in whom the histopathological stage was advanced, the APTT was prolonged, or the platelet count was increased.

[Clinical analysis of resected pulmonary pleomorphic carcinoma]

OBJECTIVE

We studied the clinical feature of pulmonary pleomorphic carcinoma.

PATIENTS

Of 1,073 patients underwent the resection of lung cancer in our hospital, 15 patients (1.4%) had primary pulmonary pleomorphic carcinoma.

RESULTS

All patients were male, and the age was ranged from 57 to 83, mean 70.3 years old. The mean Brinkman Index was 1,028.7. Thirteen patients underwent the lobectomy with lymph node dissection, 1 patient underwent the bilobectomy with lymph node dissection, and the wedge resection was done for the remaining one. Four patients were in stage IA, 5 were in stage IB, 2 were in stage IIB, 1 was in stage IIIA, 2 were in stage IIIB, and 1 was in stage IV. Histologically, the vascular invasion was showed in 8 of 15 patients. The recurrence was occurred on 9 patients, from 1 to 20 months after surgery. The site of recurrence was lung in 3 patients, brain in 3, and abdominal lymphnodes, subcutaneous soft tissue of shoulder, carcinomatous pleurisy was observed in one patient each. The 1-year survival was 62.5% , and the 3-year survival was 46.9%. Conclusion : The prognosis for pulmonary pleomorphic carcinoma is poor. More meticulous follow up is necessary for patients with pleomorphic carcinoma than those with common non-small cell carcinoma.

Expression and significance of Tie-1 and Tie-2 receptors, and angiopoietins-1, 2 and 4 in colorectal adenocarcinoma: Immunohistochemical analysis and correlation with clinicopathological factors

AIM: There is strong evidence that tyrosine kinases are involved in the regulation of tumor progression, cellular growth and differentiation. Recently, many kinds of tyrosine kinase receptors have been reported, among them Tie-1 and Tie-2 receptors constitute a major class. Angiopoietin (Ang)-1 is known as a ligand of Tie-2 tyrosine kinase receptor. The objective of this study was to establish a comprehensive Tie-1 and Tie-2 and Ang-1, 2 and 4 expression profile in human colorectal adenocarcinomas.

METHODS: We examined 96 cases of surgically resected human colorectal adenocarcinoma by immunohistochemistry and investigated the statistical correlation between the expressions of Ties and Angs and clinicopathological factors.

RESULTS: Among the 96 cases of adenocarcinoma, 87 (90.6%), 92 (95.8%), 83 (86.5%), 89 (92.7%), and 76 cases (79.2%) showed positive staining in the cytoplasm of carcinoma cells for the Tie-1 and Tie-2 and Ang-1, 2 and 4 proteins, respectively. Histologically, the expressions of Ties and Angs were variable. The expressions of Ties and Angs were correlated with several clinicopathological factors, but did not correlate with the presence of lymph node metastasis. Ties and Angs were highly expressed in human colorectal adenocarcinoma cells.

CONCLUSION: These findings suggest that the Tie-Ang receptor-ligand complex is one of the factors involved in the cellular differentiation and progression of human colorectal adenocarcinoma.