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Background Isolated mediastinal metastasis from a malignant tumor and small cell carcinoma of the bladder are both very rare. Case presentation A 76-year-old woman who had undergone surgery for bladder cancer twice was referred to our hospital for a right paracardiac mass noted in chest computed tomography findings, and resection of the tumor was performed. Histological analysis of the mediastinal tumor revealed it to be a metastatic small cell carcinoma of the bladder. At 4 months after surgery, multiple metastatic lesions were found in the chest and liver, and chemotherapy for small cell carcinoma was started. Conclusions We present this case of mediastinal metastasis of small cell carcinoma of the bladder, which is very rare, to show the importance of surgical resection of an isolated mediastinal tumor. Such a procedure should be considered, as histological diagnosis of the tumor could be useful for determining therapeutic options.

Introduction Next-generation sequencing (NGS) of multiple metastases in an advanced cancer patient reveals the evolutional history of the tumor. The evolutionary model is clinically valuable because it reflects the future course of the tumorigenic process and prognosis of the patient. Materials and Methods We experienced two lung cancer patients whose clinical courses were abruptly deteriorating resulting in very poor prognosis. To investigate the evolutionary model of these patients, we performed targeted sequencing covering whole exons of 53 significantly mutated genes associated with lung cancer of multiple metastases by autopsy. We conducted PyClone analysis to infer subclonal archtecture of multi-lesional samples. Results The NGS analysis revealed both patients harboring multiple clonal driver mutations. In Case.1, KRAS Q61H, KEAP1 G333C, STK11 K312*, RBM10 Q320* and MGA I1429V and in Case.2, TP53 R337L, TP53 Q192*, PTEN W274C, RB1 P29fs and CREBBP P696L with high allele fraction were detected in all lesions. These mutations were clustered and occupied major population across multi-lesional tumor samples. Our data suggested their lung cancers progressed with punctuated and big bang evolutional model. Conclusion We should pay attention to clinical course of lung cancer patients harboring multiple clonal driver mutations in their primary lesions. Their punctuated and big bang evolutionary process could develop systemic clinically undetectable metastases with an unexpected speed.

Objectives: For patients with multiple small-sized pulmonary cancers, a lobectomy can disrupt future therapeutic options for other lesions. It was recently reported that limited pulmonary resections were not inferior to lobectomy for the management of selected peripheral small-sized pulmonary adenocarcinomas. Patients with adenocarcinoma in situ or minimally invasive adenocarcinoma, as proposed by the International Association for the Study of Cancer classification, have been reported to have 100% survival after 5 years. However, that classification can be applied postoperatively. Since 2005, we have been intentionally performing limited pulmonary resection procedures for small-sized adenocarcinoma cases based on intraoperative imprint cytological diagnosis and our classification (Nakayama-Higashiyama's classification). Materials and Methods: A total of 120 consecutive cases were included in this study. Lung tumors were removed intraoperatively by wedge resection, and stump smear cytology was performed, from which the cases were classified into 5 groups based on our classification. When the tumor was classified as Group I or II, the operation was finished. When diagnosed as a more advanced classification, a lobectomy and lymph node dissection were additionally performed. Results: The 5-year survival rate for Group I and II was 100%, while those for Group III and IV-V were 95.8% and 94.4%, respectively. The 5-year disease-free survival rates for Group I and Group II were 100% and 97.1%, respectively, and for Group III and IV-V they were 100% and 94.1%, respectively. Conclusion: Use of cytological findings along with Nakayama-Higashiyama's classification for determining operation procedure is effective for treatment of patients with small-sized pulmonary adenocarcinoma.

Objectives: Small-size lung lesions suspected of being cancer are now often being identified on computed tomography. Correspondingly, a new lung cancer staging system has been proposed by the International Association for the Study of Lung Cancer (IASLC), in which the T1 factor and adenocarcinoma are re-subclassified. Previously, we proposed an intraoperative cytological diagnosis and its classification of small-size lung adenocarcinoma, which correlated significantly with clinical malignancy, to be used for selecting the surgical strategy. In the current study, the correlation of our intraoperative cytological classification with the new 8th IASLC classification was investigated. Materials and Methods: A total of 139 consecutive small-size lung adenocarcinoma cases were surgically resected from 2000 to 2006 and included in this study. Intraoperative stump imprint cytology using these specimens was performed, and the cases were classified into 5 groups based on our classification. The cytological classification was compared with the IASLC classification and the WHO histopathological grading. Results: According to our classification, 32 patients were in Group I, 38 in Group II, 24 in Group III, 27 in Group IV, and 18 in Group V. Compared with the IASLC classification, most of Group I was pTis or pT1mi, and most of Group II was pT1mi or pT1a (p

Background: Recently, therapeutic strategies for a metastasectomy from colorectal carcinoma after chemo-targeted therapy with bevacizumab have been presented, with which some uncommon but serious adverse events have been reported. However, only few reports have investigated the safety of lung resection after such therapy or the histological effects. We retrospectively analyzed the both of them at our institute. Methods: Of 69 colorectal carcinoma patients who underwent pulmonary metastasectomy procedures from 2009 to 2014, we investigated 11 who also received chemo-targeted therapy prior to surgery. Results: In addition to bevacizumab, 5 fluorouracil (FU)/leucovorin + oxaliplatin or capecitabine was given in 6 cases and 5 FU/leucovorin + irinotecan in 5 cases. The mean period from the end of chemo-targeted therapy to surgery was 2.7 ± 0.9 months. The response to therapy shown in imaging findings was progressive disease in 6, stable disease in 3, and partial response in 2 (response rate, 18.2%). The operation modes were wedge resection (n = 8, 72.3%), segmentectomy (n = 2, 1 in bilateral lobes, 1 in the right lobe, 18.2%), and lobectomy (n = 1, left lower lobectomy, 9.1%). All patients safely underwent a complete resection. As for postsurgical complications, chylothorax occurred in 1 case and prolonged pulmonary air leakage in 1 case. The histological effects of chemo-targeted therapy were slight. There was no relationship between histological findings with imaging findings obtained prior to the operation (p = 0.63). The 5-year disease-free survival rate after metastasectomy was 10.9%. Conclusions: Pulmonary metastasectomy after chemo-targeted therapy for colorectal carcinoma patients obtained acceptable results. In addition, there was no correlation between imaging and histopathologic results following chemo-targeted therapy.

Background To prevent postoperative middle lobe torsion after a right upper lobectomy, we introduced a novel technique of interlobar fixation using collagen fleece coated with fibrin. In this study, the prophylactic effects of this method on the incidence of postoperative pulmonary torsion were analyzed. Methods Between April 2001 and December 2015, 3786 pulmonary resection procedures (excluding total pneumonectomy) were performed in our institution, and prophylactic interlobar fixation was selectively applied when intraoperative examination indicated that the patient was at high risk of postoperative pulmonary lobe torsion. As a control group, 842 patients who underwent pulmonary resection procedures between January 1996 and April 2001 were reviewed. Results During the study period, 10 (0.3%) patients underwent prophylactic middle lobe fixation (to the lower lobe after a right upper lobectomy in 9, and to the upper lobe after a right lower lobectomy in one). Pulmonary lobar (middle lobe) torsion occurred in only one patient (after right upper lobectomy); thus the incidence of this complication was 0.1% among patients who underwent a right upper lobectomy and 0.03% among all pulmonary resection procedures. The rates during the study period were marginally significantly lower than those in the control period (1.3% and 0.24%, respectively; p = 0.071 and p = 0.087, respectively). Conclusion Prophylactic middle lobe fixation might be useful for preventing postoperative pulmonary middle lobe torsion.

We propose a cost-effective and scalable OXC/ROADM that consists of a subsystem-modular express switch part and a transponder-bank-based add/drop part. The effectiveness of the proposed architecture is verified via a hardware scale evaluation, network performance simulations, and transmission experiments. The architecture enables large throughput and offers significant hardware-scale reductions with marginal fiber-utilization penalty against the conventional architectures. A part of the OXC/ROADM designed to accommodate 35x35 express fiber ports and 2,800 transponders for add/drop is constructed. Its net throughput reaches 314 Tbps using 80 channels of 120-Gbps signal (30-Gbaud dual-polarization quadrature phase-shift-keying signals with 7% overhead are assumed).

We demonstrate novel large-scale and cost-effective ROADM architecture exploiting the subsystem-modular express switches and tailored transponder banks for add/drop functionality. Simulations show that the proposed ROADM offers virtual-C/D/C performance. Good transmission characteristics are experimentally confirmed.

We propose a novel add/drop architecture that suits large-scale optical cross-connect (OXC) nodes with subsystem modular architecture. Substantial hardware reduction is attained while the throughput offset is shown to be marginal.

We propose a novel add/drop architecture that suits recently proposed cost-effective large-scale optical cross-connect (OXC) nodes. The proposed architecture connects each transponder bank to a limited number of incoming/outgoing fibers and attains virtually the same routing performance as the ideal add/drop architecture. This is made possible by our newly developed routing and wavelength assignment algorithm that considers the add/drop constraint. In combination with the subsystem-modular OXC node architecture, significant hardware scale reduction can be yielded. Numerical experiments demonstrate that the hardware scale of the proposed add/drop architecture is reduced by 40 % at the cost of slight decrease in throughput.

We propose novel highly scalable subsystem modular optical cross connect (OXC) architectures that use an efficient add/drop part to connect each transponder bank to a limited number of incoming/outgoing fibers. We investigate the performance and hardware scale of the proposed architectures in two add/drop configurations. Numerical evaluations prove that the proposed architectures attain almost the same routing performance as the equivalent conventional single large-scale OXC with an ideal colorless, directionless, and contentionless add/drop part, while enabling substantial hardware scale reduction.

Laboratory experiments were performed to evaluate boundary-layer transfer coefficients for fluttering plant leaves in winds at various mean attack angles to the fluctuating flow. In these experiments, water vapor transfer was investigated by using rectangular flat leaf models of various dimensions fluttering resonantly with the fluctuation of artificial air streams with similar intensities of turbulence to natural flows within plant canopies. Most of the water-vapor transfer coefficients evaluated for upstream-and downstream-facing surfaces were larger than those estimated from the laminar boundary-layer theory. In a range of Reynolds numbers below a critical value between 3×103 and 3×104, the transfer coefficients were apparently proportional to the square root of the mean flow speed. Under this Reynolds number range, the ratio of the experimental transfer coefficient to that estimated from the theory was expressed as a function of the model dimensions at each fluttering number and at each attack angle.The enhancement of the transfer coefficients for fluttering leaf models at various attack angles is discussed in conjunction with fluid turbulence, large eddies, the pressure distribution over the model surface and the model-fluttering.