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Background Nicotinamide adenine dinucleotide phosphate (NADPH) Oxidases (NOXs) are transmembrane proteins that generate reactive oxygen species. Recent studies have reported that NOXs play important roles in the progression of various cancers. However, the expression and role of NOX2 in colon cancer is unclear. Therefore, this study aimed to investigate the expression of NOX2 and effects on the prognosis of patients with colon cancer, and also examined the pathophysiological role of NOX2 in cell proliferation and motility. Methods We used 116 primary colon cancer samples obtained from patients who underwent curative resection for stage II or III colon cancer for immunohistochemistry to assess the relationship between NOX2 expression and clinicopathological factors and evaluate the prognostic significance of NOX2 expression in colon cancer patients. The expression levels of NOX2 protein and mRNA in human colon cancer cell lines were analyzed and two highly NOX2 expressed cell lines (HCT116 and RKO) were used for further study. Knockdown experiments with NOX2 siRNA were performed, and the effects on cell proliferation, cell cycle progression, migration, and invasion were analyzed. Results Immunohistochemical staining revealed that NOX2 protein was scarcely expressed in noncancerous tissue compared to cancer tissue, and 45 samples (38.8%) had positive staining for NOX2 expression in cancer tissue. No clinicopathological factor was significantly associated with NOX2 expression. The 5-year recurrence-free survival rate of the NOX2 positive group was significantly lower than that of the NOX2 negative group (61.1% vs. 79.3%, p = 0.029). NOX2 depletion using siRNA significantly inhibited cell proliferation, G1 to S phase cell cycle progression, migration, and invasion in the two cell lines. Conclusions NOX2 expression affects the prognosis of colon cancer patients, as well as the tumorigenesis of colon cancer cells. NOX2 may be a novel biomarker and therapeutic target for colon cancer patients.

We divided the patients with biliary tract cancer who underwent pancreaticoduodenectomy(PD)at our hospital into the 5-year recurrence-free and recurrence groups and investigated the prognostic factors. Additionally, we investigated the efficacy of adjuvant chemotherapy in patients with and without lymph node (LN) metastasis. There was no significant difference between the two groups for patient characteristics and perioperative factors. However, patients with LN metastasis tended to have a higher recurrence rate. For patients without LN metastasis, the median overall survival(OS)was not significantly different between the patients who received and did not receive adjuvant chemotherapy. For patients with LN metastasis, although it was not significantly different(p=0.234), the OS of patients who received adjuvant therapy was more than 3 times than that of patients who did not(58.6 months and 18.4 months, respectively). For patients with biliary tract cancer who underwent PD, positive LN metastasis may be a poor prognostic factor, and adjuvant therapy may possibly improve prognosis.

Background Nodular fasciitis (NF) is a type of rare and rapidly growing tumor that affects the muscular fascial layers. Due to its locally aggressive nature and rapid growth, NF can be mistaken as a malignant process on either clinical or histological grounds. Case presentation A 61-year-old man was affected by rectal cancer. We performed a robotic, high-anterior resection with lymph node dissection. According to the 8th edition of Union for International Cancer Control, the diagnosis was stage I pT2N0M0. During a routine follow-up 1.5 years after the robotic surgery, a computed tomography examination revealed a tumor in the upper right abdominal wall, at the site of the surgical port, that measured 45 mm. Magnetic resonance imaging indicated a hypo-intensive mass within the right straight muscle of the abdomen. Port site recurrence following the robotic surgery for rectal cancer was suspected, and an ultrasound-guided fine-needle aspiration was performed; it revealed a low-grade myofibroblastic tumor or benign neoplasm, but was inconclusive. We performed an excision of the lesion, and histopathology confirmed NF, seen as a solid, nodular, spindle-cell lesion. The patient was postoperatively followed for more than 1 year without any sign of recurrence of either cancer or NF. Conclusions NF is histologically benign, but local recurrence frequently occurs. We encountered a patient with NF at the port site after robotic surgery for rectal cancer.

In this study, we aimed to analyse human cancer cell–platelet interactions in functional cell analyses and explore the molecular mechanisms behind tumour progression. Various functional analyses of gastric cancer (GC) cells were performed after direct/indirect co-incubation with platelets derived from GC patients. Further detailed expression and signalling analyses were performed after co-culture with direct and indirect GC cells–platelet contact. Malignant behaviours of cancer cells, such as proliferation, migration, invasion and adhesion, were significantly enhanced after direct co-incubation with platelets. Microarray analyses demonstrated changes in multiple genes, including epithelial–mesenchymal transition (EMT)-related genes. Among them, matrix metalloproteinase 9 was notably upregulated, which was validated by quantitative reverse transcription–polymerase chain reaction and western blot. Further, this change was only observed after direct co-incubation with platelets. This study demonstrated that platelets from GC patients promote malignant behaviours of GC cells through EMT-related signalling, especially by direct contact with tumour cells.

Objectives: Rectal stump washout has been widely performed to prevent the implantation of exfoliated cancer cells (ECCs) in patients with rectal cancer. However, it remains unclear whether intraluminal washout before transection is required in patients with sigmoid colon cancer. Therefore, this pilot study was conducted to elucidate the necessity of intraluminal washout for sigmoid colon cancer patients in comparison with rectal cancer patients by cytological assessments. Methods: A total of 16 patients with sigmoid colon cancer and 24 patients with rectal cancer who underwent sigmoidectomy or anterior resection with anastomosis using double-stapling technique were enrolled. A transanal washout sample was collected before washout and after irrigation with 500 and 1,000 mL of saline. Cytological assessments were conducted according to the Papanicolaou classification, and class IV and V cells were defined as malignant. Results: Before washout, exfoliated cancer cells were found in 15 of 24 (62.5%) patients with rectal cancer and in 1 of 16 (6.2%) patients with sigmoid colon cancer (p < 0.001). Distal-free margin from the tumor was significantly shorter in patients with cancer cells (p = 0.002), and the length of the distal-free margin was significantly associated with the tumor location. After irrigation with 500 and 1,000 mL of saline, no cancer cell was found in all patients with sigmoid colon cancer, whereas ECCs were still found in five patients with rectal cancer (20.8%). Conclusions: Intraluminal washout with 1,000 mL may be sufficient for sigmoid colon cancer patients with longer distal-free margin. A large-scale, randomized controlled study is necessary to confirm these results.

We report on 25 Gbaud PAM4 communication in the 300 GHz-band, which employs an integrated-optic PAM signal emulator with a tunable asymmetric Mach-Zehnder interferometer configuration. We did not adopt special signal processing or coherent detection.

The prognosis of gastric cancer patients with positive lavage cytology without gross peritoneal dissemination (P0CY1) is poor. The survival benefit of gastrectomy for these patients has not been established.In this population-based cohort study, we investigated the impact of radical gastrectomy with lymph node dissection for P0CY1 patients. Patients who were diagnosed with Stage IV gastric cancer from 2008 to 2015 in all nine cancer-designated hospitals in a tertiary medical area were listed. Patients who were diagnosed with histologically proven adenocarcinoma in both the primary lesion and lavage cytology during the operation or a diagnostic laparoscopic examination were enrolled. Patients with a gross peritoneal lesion or other metastatic lesions were excluded. The primary outcome was the adjusted hazard ratio (aHR) of gastrectomy for overall survival. We also evaluated the survival time in patients who underwent gastrectomy or chemotherapy in comparison to patients managed without primary surgery or with best supportive care.One hundred patients were enrolled. The aHR (95% confidence interval) of gastrectomy was 0.677 (0.411-1.114, p = 0.125). The median survival time in patients who received gastrectomy (n = 74) was 21.7, while that in patients managed without primary surgery (n = 30) was 20.5 months (p = 0.155). The median survival time in patients who received chemotherapy (n = 76) was 23.0 months, while that in patients managed without chemotherapy was 8.6 months (p 0.001).Gastrectomy was not effective for improving the survival time in patients with P0CY1 gastric cancer. Surgeons should prioritize the performance of chemotherapy over surgery as the initial treatment.

Diffuse‑type gastric cancer, also known as scirrhous gastric cancer, is characterized by a larger number of stromal cells, referred to as cancer‑associated fibroblasts (CAFs), than the number of cancer cells in the tissue. The present study focused on CAFs in gastric cancer and examined their potential as a blood biomarker. A total of 46 and 84 patients with gastric cancer were respectively included in a development and an independent validation cohort to assess the clinicopathological characteristics of plasma podoplanin (PDPN) levels. The prognostic impact of plasma PDPN was also investigated in the validation cohort. The cut‑off value of the plasma‑PDPN concentration was set to the median plasma PDPN concentration in the development cohort that was then divided into the high‑PDPN and low‑PDPN groups. The high‑PDPN group tended to have more diffuse‑type disease (P=0.079), which was further confirmed through logistic regression analysis (P=0.008). Kaplan‑Meier survival estimates indicated that the recurrence‑free survival rate was significantly lower in the high‑PDPN group (P=0.029). In conclusion, plasma soluble PDPN was demonstrated to be a marker for diffuse gastric cancer and may reflect the prognosis of this disease.

Background/aim We investigated the clinical impact of the primary tumor site in stage IV colorectal cancer (CRC). Patients and methods In this statewide multicenter retrospective cohort, patients with stage IV CRC from nine hospital-based cancer registries across the Fukushima Prefecture (2008-2015) were categorized based on three primary tumor sites: right colon cancer (RCC), left colon cancer (LCC), and rectal cancer. Overall survival was assessed using Cox regression analysis. Results A total of 1,211 patients were included. The most common clinical symptom was obstruction in LCC and bleeding in rectal cancer. Liver metastases were multiple and larger in LCC, while lung metastases were multiple in rectal cancer. Compared to LCC, the adjusted hazard ratio (HR) for overall survival was 1.19 [95% confidence interval (CI)=1.01-1.39, p=0.032] in RCC and 1.03 (95% CI=0.86-1.23, p=0.77) in rectal cancer. Conclusion RCC was independently associated with a worse prognosis in stage IV CRC.

We report on a tunable integrated-optic circuit for demultiplexing optical orthogonal frequency division multiplexing (OFDM) signals with various number of sub-carrier channels. The demultiplexer is composed of tunable optical discrete Fourier transform filter (tunable couplers, delay lines, and a slab star coupler) and optical gates. Various sub-carrier number optical OFDM signals can be demultiplexed by selecting the active delay lines with the tunable couplers. After explaining the demultiplexer and its operating principle, we show some experimental results including transmittance and bit error rate measurement of demultiplexed sub-carriers from various sub-carrier number optical OFDM signals. $2 \times 10$ Gbit/s to $10 \times 10$ Gbit/s OFDM signals could be successfully demultiplexed.

Wireless communication using a pulse amplitude modulation signal was carried out in the 300 GHz-band. In this investigation, the used THz-wave signal was generated with a silica waveguide-type optical signal emulator and high-speed photo-mixing. The optical signal emulator consisting of a tunable asymmetric Mach-Zehnder interferometer produces an optical pulse amplitude modulation signal from an optical on-off keying signal by partly adopting lightwave interference. 25 Gsymbol/s three and four-level pulse amplitude modulation signals in the 300 GHz-band were generated and used for the wireless communication. Bit error rates of received signals were evaluated with off-line processing, and the bit error rates were estimated to be 1.9 × 10−4 and 8.0 × 10−3 in the communications using the three and four-level signals, respectively.

Purpose: With the aging of society, the age of patients with gastric cancer (GC) in Japan has been increasing. However, there are few documented outcomes for young patients with stage IV GC. We investigated the clinical characteristics and prognosis of patients with stage IV GC aged under 40 years using a dataset from an integrated population-based cohort study.Methods: We conducted this multicenter population-based cohort study to determine whether earlier onset of GC was a poor prognostic factor. We enrolled patients with metastatic GC aged under 40 years (young group) and those aged between 60 and 75 years (middle-aged group). Patients were histologically diagnosed as having gastric adenocarcinoma. We evaluated the overall survival (OS) of both groups and the hazard ratio (HR) for OS based on age. The adjusted HR with 95% confidence interval (CI) was evaluated using the Cox proportional hazards model after adjusting for confounding factors, including sex, histology, number of metastatic lesions, surgical resection, and chemotherapy.Results: This study enrolled 555 patients. The patients were classified into the young group (n=20) and the middle-aged group (n=535). The median OS values were 5.7 months and 8.8 months in the young and middle-aged groups, respectively (P=0.029). The adjusted HR (95% CI) of the young group was 1.88 (1.17–3.04, P=0.009).Conclusions: Age was an independent prognostic factor in patients with stage IV GC. Further studies investigating the genomic characteristics of GC and exploring more effective chemotherapeutic agents are required.

Objective The prognosis of patients with liver metastases from gastric cancer is determined using tumor size and number of metastases; this is similar to the factors used for the prediction of liver metastases from colorectal cancer. The relationship between the degree of liver metastasis from gastric cancer and prognosis with reference to the classification of liver metastasis from colorectal cancer was investigated. Methods This was a multi-institutional historical cohort study. Among patients with stage IV gastric cancer, who visited the cancer hospitals in Fukushima Prefecture, Japan, between 2008 and 2015, those with simultaneous liver metastasis were included. Abdominal pretreatment computed tomography images were reviewed and classified into H1 (four or less liver metastases with a maximum diameter of ≤5 cm); H2 (other than H1 and H3) or H3 (five or more liver metastases with a maximum diameter of ≥5 cm). The hazard ratio for overall survival according to the H grade (H1, H2 and H3) was calculated using the Cox proportional hazards model. Results A total of 412 patients were analyzed. Patients with H1, H2 and H3 grades were 118, 162 and 141, respectively, and their median survival time was 10.2, 5.7 and 3.1 months, respectively (log-rank P Conclusions The grading system proposed in this study was a simple and easy-to-use prognosis prediction index for patients with liver metastasis from gastric cancer.

Background Traditionally, the surgery for simultaneous double cancer of the stomach and colon required a large incision to the upper and lower region of the abdomen. In this case, an artificial blood vessel was located under the skin after revascularization. Considering ischemia due to graft compression by incision retractor during laparotomy, this was difficult to do. This is a report on laparoscopic surgery for simultaneous double cancer of the stomach and colon after revascularization. Case presentation A 69-year-old man had early gastric cancer and advanced sigmoid colon cancer. He had suffered from thromboangitis obliterans and has undergone revascularization many times due to poor blood flow in his lower limbs. He had had some artificial blood vessels inserted under the skin, confirmed by blood vessel construction image by preoperative computed tomography (CT). There was a bypass vessel from the left axillary artery to the left femoral artery under the skin of the left thoracoabdominal. In addition, there were two bypass vessels from the left external iliac artery to the right femoral artery under the skin of the lower abdomen. One of the two bypasses was occluded. In the blood flow to the intestinal tract, the inferior mesenteric artery was already occluded. Peripheral blood flow in the common iliac artery depended on blood flow from the artificial blood vessel, and blood flow from the internal iliac artery to the rectum was poor. Laparoscopic Hartmann’s operation was performed for Stage II B (UICC 8th Edition) sigmoid colon cancer. Because the blood flow in the intestinal tract on the anal side was poor, we thought that anastomosis was at a high risk for leakage. Laparoscopic total gastrectomy was also performed simultaneously for two Stage I (UICC 8th edition) gastric cancers in the cardia and body. The location of the port site and stoma was carefully determined preoperatively to prevent damage and infection to the artificial blood vessels. Minimal invasive surgery was performed using laparoscopic surgery. Conclusions Laparoscopic surgery with small incisions is useful for patients with double cancer who need an approach to the upper and lower abdomen. Furthermore, laparoscopic surgery has less interference on graft in patients with artificial blood vessels under the skin by intraperitoneal approach.

We report on Nyquist wavelength division multiplexing (WDM) communication in the terahertz (THz)-band utilizing an integrated-optic spectrum synthesizer. The synthesizer is composed of two arrayed-waveguide gratings, and an array of phase shifters and variable optical attenuators, and it can individually control amplitude and phases of up to 64 optical discrete frequency components with 40 GHz spacing. Three optical frequency combs are produced by combining the synthesizer with a mode-locked laser diode. The produced combs are used to generate a THz-wave Nyquist WDM signal with photo-mixing. We demonstrate 2 x 40 Gbit/s Nyquist WDM communication in the 300 GHz band.

Pancreatectomy is a highly invasive procedure with extensive intraoperative blood loss (IBL) and high risk of postoperative pancreatic fistula (POPF). We conducted an experimental and retrospective clinical study to determine whether the malignant behaviors of pancreatic cancer cells were enhanced by exposure to blood components in vitro and to evaluate the oncological significance of high IBL and POPF in pancreatic cancer. This study included 107 patients undergoing radical pancreatectomy in the University of Yamanashi Hospital between 2011 and 2017, classified into high (n = 29) and low (n = 78) IBL groups. In vitro experiments included functional analyses of Panc-1 pancreatic cancer and normal mesothelial cells exposed to patient blood components, and clinical data were used to assess the contribution of IBL and POPF to patient outcomes. The migration (p = 0.007), invasion (p < 0.001), and proliferation (p < 0.01) of Panc-1 cells were enhanced with platelet coculture. The ability of Panc-1 cells to adhere mesothelial cells was enhanced by plasma coincubation, especially in the presence of inflammation (p < 0.001). High IBL was associated with worse overall survival (p = 0.007) and increased locoregional recurrence (p = 0.003) in patients. POPF enhanced the negative prognostic significance of high IBL (p < 0.001 for overall survival, p = 0.001 for locoregional recurrence), indicating the oncological negative effects of high IBL and POPF. Blood components, especially platelets, and inflammation enhance the malignant behaviors of pancreatic cancer cells, potentially contributing to poor prognosis for pancreatic cancer patients.

The clinical significance of lymph node micrometastasis (LNMM) remains controversial in gastric cancer (GC). In this study, we investigated the prognostic impact of LNMM in patients with GC. A total of 624 patients with pathologically lymph node metastasis-negative (pN0) and N1 status (pN1) who underwent gastrectomy between 2004 and 2018 were enrolled in this retrospective study. The diameter of tumor cell clusters in metastatic lymph nodes was measured in 120 patients with pN1 GC. Patients with lymph node tumors

50's man who have performed anterior pelvic exenteration with lateral lymph node dissection for rectal cancer with pT4bN0M0, pStage Ⅱc about 2 years ago, was admitted to our hospital for the treatment of intrapelvic recurrence of rectal cancer. No distant metastasis was found in the computed tomography examination but the tumor invaded the dorsal side of the pubis. Because radical excision was impossible with these findings, he received chemoradiotherapy(CRT). Post-CRT imaging showed that the tumor of intrapelvic recurrence region reduced the size, and invasion of pubis had disappeared and been markedly reduced. Thus, radical excision seemed possible at this point, and we decided to attempt operation after total 6 weeks of S-1(120 mg/day)regimen and radiation(40 Gy/20 Fr). We performed Miles' operation. The final pathological examination demonstrated that no viable tumor cells remained in the resected rectum specimen, confirming that a pathological complete response(pCR)had been achieved.

It remains unclear whether intensive chemotherapy for Stage IV colorectal cancer (CRC) patients aged 80 years or older is beneficial prognostically. This study aimed to investigate the overall survival of Stage IV CRC patients aged ≥ 80 years receiving intensive chemotherapy. The study design was a population-based, multicenter, historical cohort study. The extracted participants’ data were consecutive patients diagnosed as Stage IV CRC between January 2008 and May 2015 in nine hospitals in Japan. Patients were classified into two groups according to age: aged group (≥ 80 years) and younger group (

We report on an integrated-optic spectrum synthesis circuit that can individually control amplitude and phase of 40 GHzspaced and 64 frequency components. This synthesis circuit is fabricated with silica waveguide technology, and is composed of two arrayed-waveguide gratings (AWGs), and an array of variable optical attenuators (VOAs) and phase shifters. The AWGs function as frequency multi/demultiplexers, and the VOA and phase shifter are used to adjust amplitude and phase of each spectral component, respectively. The size of the circuit is 80 mm x 80 mm, and the manipulation accuracy relating to the VOA and phase shifter is in the order of 0.1 dB and 0.01, respectively. The VOA extinction ratio, namely, the dynamic range is about 30 dB.

We report variable capacity THz-wave communication using Nyquist pulses, which is realized by changing the channel number and optical-domain filtering of received signals. We carried out 10 to 40 Gsymbol/s communication in the 300 GHz-band.

We report an integrated-optic spectrum synthesizer with loop-back paths and an interleaved filter, which can independently manipulate the amplitude and phase of 10 GHz- spaced frequency components. We applied the synthesizer to optical OFDM signal generation.

Transmission characteristics of an optical signal, which is converted from a high-speed terahertz-wave signal with high spectral efficiency, are investigated and reported. A Nyquist time division multiplexing 40 Gbit/s on–off keying signal in the terahertz band is generated with high-speed photo-mixing. The generated terahertz-wave signal is again converted into an optical signal with heterodyne detection, optical intensity modulation, and optical filtering. Then the chromatic dispersion tolerance of the converted optical signal is investigated in order to obtain knowledge for realising the connection between the fibre-optic and the wireless links. After briefly explaining the conversion method, some related experimental results are reported. The results include evaluation of chromatic dispersion tolerance with regard to the optical signal at the final stage. As a sequel to bit error rate measurement, the optical signal can be transmitted to a 9 km-long single-mode fibre without chromatic dispersion compensation.

Objectives Nutritional status significantly influences postoperative prognosis in gastrointestinal cancers. It has been evaluated using sarcopenia before treatments such as surgery and chemotherapy, despite constant changes in nutritional status. We consider that nutritional status at cancer recurrence is one of the important factors that affect treatment choice and intensity. This study evaluated the prognostic effects of improved postoperative nutritional status for people with colorectal cancer recurrence. Methods We enrolled 209 participants with pathologically confirmed stage II or III colorectal cancer who underwent radical resection. Sarcopenia was diagnosed using the psoas muscle index obtained from analysis of three-dimensional computed tomographic images. We adopted the cutoff value that was proposed by Hamaguchi et al. (psoas muscle index Results Among the 209 participants, 81 (38.8%) had preoperative sarcopenia; this group had significantly lower overall survival than those without sarcopenia (P = 0.028). Colorectal cancer recurred in 48 participants. Of those 46, sarcopenia was evaluated at the time of recurrence; 19 of those 46 had preoperative sarcopenia. Preoperative sarcopenia did not affect the cancer recurrence ratio (sarcopenia, 23.5%; non-sarcopenia, 21.3%; P = 0.893). The sarcopenia-improvement group had higher overall survival than the sarcopenia-continuation group (P = 0.042). Conclusions Among participants with preoperative sarcopenia, the prognosis at the time of recurrence improved for the sarcopenia-improvement group compared to the sarcopenia-continuation group. In people with colorectal cancer and sarcopenia, nutritional management is important not only before but also after surgery.

Spectrally efficient optical communication with flexible capacity is required in the prospective adaptive photonic network. Optical orthogonal frequency division multiplexing (OFDM) is one of candidates to contribute to this type of photonic network. Here we report on a gate-free integrated-optic tunable filter that can demultiplex optical OFDM signals with various number and symbol rate sub-carrier channels. The filter consists of tunable couplers, an array of delay lines, and a slab star coupler-type optical Fourier transformation circuit. We can tune the number and/or the symbol rate of demultiplexed optical OFDM channels by selecting the delay lines with the tunable couplers. Optical timing gates were normally attached to the filter output ports with a view to extracting the effective time of the filtered channels. In this investigation, we removed the optical gates and substituted a high-speed photodetector for the gate with a view to achieving completely passive demultiplexing of the various capacity optical OFDM signals. Various channel symbol rate and channel number OFDM signals (5 × 10 to 20 Gsymbol/s and 3 × 20 Gsymbol/s) were successfully demultiplexed with this gate-free tunable filter. Our star coupler-type tunable OFDM filter without the gates was used to demultiplex various channel symbol rate optical OFDM signals for the first time.