Electrosurgical knife with the water-jet function of tip-type during endoscopic treatment injection.

Objectives: This study aimed to objectively evaluate the water-jet-functioned electrosurgical knife injection performances in a desktop experiment. Methods: Five types of water-jet-functioned electrosurgical knives, including two injection styles of sheath-type (A: DualKnife J, KD-655L; B: FlushKnife, DK2620-J-B20S; C: Splash M-Knife, DN-D2718B; D: ISSEN, SN1650-20) and tip-type (E: ORISE ProKnife, M00519361) were evaluated. These knives were compared with an injection needle (Control: SuperGrip 25G) as a control. The injection speed under constant pressure and the injection efficiency for each knife against prepared porcine stomach mucosa were evaluated. The additional clear gel injections using an injection needle were observed using an indigo blue-colored gel to evaluate the difference between the locations of water-jet holes. Results: Four types of knives, except for A, showed significantly higher water-jet speeds (A: 0.79 ± 0.03 g/20 s, B: 2.56 ± 0.05 g/20 s, C: 3.09 ± 0.06 g/20 s, D: 2.86 ± 0.05 g/20 s, and E: 1.79 ± 0.03 g/20 s) compared to that of the control (1.21 ± 0.03 g/20 s). Meanwhile, significantly higher efficacy of injection was found in the tip-type water-jet function knife, second to the injection needle (Control: 37.2% ± 35.5%, A: 20.9% ± 20.2%, B: 1.1% ± 2.2%, C: 6.2% ± 12.6%, D: 12.5% ± 15.6%, and E: 33.3% ± 32.2%). An additional injection experiment revealed that the injection with a piercing tip into the gel could achieve sufficient additional injection inside the stacked clear gel. Conclusions: The tip-type water-jet function electrosurgical knife is preferable for effective submucosal injection during endoscopic treatments.

[Selection of Operative Procedure for Breast Cancer in Carriers of BRCA VUS in Japan].

Risk classification and clinical management of the DNA variant of unknown significance(VUS)in BRCA 1/2 remains unestablished. The Japanese hereditary breast and ovarian cancer(HBOC)consortium and myriad genetics reported that the VUS rate of BRCA is 6.5% in Japanese patients, but is <2% in the USA. The types of mutation supposedly differ between Asian and European ethnicities. Breast-conserving therapy(BCT)is not recommended in HBOC breast cancer, according to the 2017 Japanese guidelines by the Ministry of Health, because of the risk of ipsilateral breast recurrence(IBR)and carcinogenesis by radiation. In our hospital, we recommend an initial mastectomy and breast reconstruction with an implant for patients with HBOC breast cancer, considering future surgery on the contralateral side and symmetry of the reconstructed breast. However, the risk of IBR after BCT is not significantly high in patients with HBOC breast cancer, and BCT is a reasonable option even for definite HBOC breast cancer under low risk conditions. Hence, BCT is feasible for treating breast cancer in carriers of VUS following decision-making and informed consent from the patients.

Prognostic Factors Affecting Survival After Multivisceral Resection in Patients with Clinical T4b Gastric Cancer.

BACKGROUND: The prognosis and survival of patients with advanced gastric cancer is poor. Although completeness of resection (R0) is one of the most important factors affecting survival, multivisceral resection (MVR) for locally advanced (clinical T4b, cT4b) gastric cancer remains controversial. The aim of this study was to evaluate the factors affecting prognosis and survival after MVR in patients with cT4b gastric cancer. METHODS: Between 2005 and 2015, we retrospectively reviewed the medical records of 103 patients who underwent MVR for cT4b gastric cancer with suspected direct invasion to adjacent organs. Patient characteristics, related complications, long-term survival, and prognostic factors of cT4b gastric cancer were analyzed. RESULTS: Postoperative mortality and morbidity rates of patients after MVR were 1.0 and 37.9%, respectively. R0 resection was achieved in 82.5% patients, all of whom had a significantly improved survival rate. Overall survival rates at 1 and 3 years were 78.3 and 47.7% for R0 resection and 46.6 and 14.3% for R1 resection, respectively (R0 vs. R1, P < 0.002). Multivariate analysis revealed that completeness of resection (R0) was an independent prognostic factor associated with longer survival. CONCLUSIONS: In patients with cT4b gastric cancer, gastrectomy with MVR to achieve an R0 resection can be performed with acceptable postoperative morbidity and mortality rates and can have a positive impact on long-term survival.

High expression of miR-181c as a predictive marker of recurrence in stage II colorectal cancer.

INTRODUCTION: A standard treatment for stage II colorectal cancer (CRC) is surgical resection without adjuvant chemotherapy. However, the recurrence rate of these patients is approximately 20%. To date, there are no robust biomarkers suitable for predicting recurrence in stage II CRC patients. In this study, microRNAs (miRNAs) extracted from CRC tissues were examined for a possible biomarker to predict recurrence in stage II CRC patients. RESULTS: From the comprehensive analysis, 15 miRNAs were selected as candidates for further study. Regarding let-7a, -7d, -7e, miR-23c, -26b, -128a, -151-5p, and -181c, recurrence rates in training cohort patients with higher expression of these miRNAs isolated from their frozen tissues samples were significantly higher than those with lower expression (P < 0.05). According to multivariate analysis, the higher expression of miR-181c was detected as an independent predictive factor of recurrence (P = 0.001, OR: 9.43, 95% CI: 2.57-34.48). Results were similar in miR-181c extracted from FFPE tissues obtained from the training cohort (P = 0.003, OR: 7.46, 95% CI: 1.97-28.57). In the validation cohort using FFPE tissues, the recurrence rate in patients with higher miR-181c expression was significantly higher than those with lower miR-181c expression (P < 0.001). MATERIALS AND METHODS: Comprehensive analysis using a highly sensitive miRNA chip was initially performed to select candidate miRNAs associated with recurrence. Candidate miRNAs were analyzed by real-time RT-PCR using RNA from frozen and formalin-fixed, paraffin-embedded (FFPE) tissues. CONCLUSIONS: Higher expression of miR-181c may be a useful recurrence predictor of stage II CRC patients.

[Fecal Biomarker for Colorectal Cancer Diagnosis].

The fecal occult blood test (FOBT) is widely used for colorectal cancer (CRC) screening to reduce the mortality rate associated with this cancer. However, several problems exist, as FOBT results can contain some false-negative CRC patients and some-false positive healthy subjects. Thus, to resolve these problems, several fecal biomarkers based on fecal protein, fecal DNA, and fecal RNA have been reported. Fecal calprotectin, which indicates intestinal bleeding or inflammation of the colon mucosa, and fecal tumor M2-PK, which is produced by cancer cells, have been extensively investigated as fecal protein biomarkers. To detect small amounts of CRC-specific proteins, the chemiluminescent enzyme immunoassay (CLEIA), which is a highly sensitive protein detection method using immunomagnetic beads, will be used. DNA mutation of APC, KRAS, and TP53 genes and DNA methylation of VIM, TFPI2, BMP3, NDRG4, and SFRP2 genes were reported as fecal DNA biomarkers. Consequently, a fecal DNA test named Cologuard from Exact Sciences was approved by the FDA in August 2014. Fecal COX2, MMP7, miR-106a, miR-92a, and miR-223 were also reported as fecal RNA biomarkers. This review article summarizes fecal biomarkers using fecal samples for CRC diagnosis.

Minimally invasive hybrid surgery combined with endoscopic and thoracoscopic approaches for submucosal tumor originating from thoracic esophagus.

BACKGROUND: Despite the efficacy of molecular targeted therapy, surgical resection remains the only curative primary treatment for gastrointestinal stromal tumors (GISTs). However, in cases when the tumor originates from the thoracic esophagus, conventional transthoracic approach is highly invasive. METHODS: All procedures were performed with patients in a prone position through a double-lumen endotracheal tube for single-lung ventilation. First, to clarify the resection layer between the tumor and mucosal layer of the esophagus, a sodium hyaluronate solution colored with indigo carmine was injected into the submucosa via the esophagoscopic approach. Second, we thoracoscopically divided the longitudinal muscle of the esophagus and enucleated the tumor through three ports by dissecting along the artificially colored submucosa, thereby minimizing accidentally opening of the esophageal mucosa. Third, we sutured the divided longitudinal muscle layer and removed the tumor from the thoracic cavity. RESULTS: Four tumors, including one GIST, were successfully resected via this hybrid approach. The mean surgical time was 137.7 min (range, 60-231 min), and the mean blood loss was 21.2 ml (range, 3-65 ml). No perioperative complications occurred, including with accidental opening of the esophageal mucosa. CONCLUSIONS: Our minimally invasive hybrid surgery combined with esophagoscopic and thoracoscopic approaches demonstrated successful resection. This surgery could have advantages both for curing esophageal submucosal tumor and for minimizing surgical invasiveness.

Gene expression analysis using a highly sensitive DNA microarray for colorectal cancer screening.

BACKGROUND/AIM: Half of all patients with small, right-sided, non-metastatic colorectal cancer (CRC) have negative results for the fecal occult blood test (FOBT). In the present study, the usefulness of CRC screening with a highly sensitive DNA microarray was evaluated in comparison with that by FOBT using fecal samples. MATERIALS AND METHODS: A total of 53 patients with CRC and 61 healthy controls were divided into "training" and "validation sets". For the gene profiling, total RNA extracted from 0.5 g of feces was hybridized to a highly sensitive DNA chip. RESULTS: The expressions of 43 genes were significantly higher in the patients with CRC than in healthy controls (p<0.05). In the training set, the sensitivity and specificity of the DNA chip assay using six genes were 85.4% and 85.2%, respectively. On the other hand, in the validation set, the sensitivity and specificity of the DNA chip assay were 85.2% and 85.7%, respectively. The sensitivities of the DNA chip assay were higher than those of FOBT in cases of the small, right-sided, early-CRC, tumor invading up to the muscularis propria (i.e. surface tumor) subgroups. In particular, the sensitivities of the DNA chip assay in the surface tumor and early-CRC subgroups were significantly higher than those of FOBT (p=0.023 and 0.019, respectively.). CONCLUSION: Gene profiling assay using a highly sensitive DNA chip was more effective than FOBT at detecting patients with small, right-sided, surface tumor, and early-stage CRC.

New molecular diagnosis and screening methods for colorectal cancer using fecal protein, DNA and RNA.

Several screening methods for reducing the mortality rate of colorectal cancer (CRC) have been reported in recent decades. Fecal occult blood tests (FOBTs) are widely used for CRC screening and immunochemical FOBTs perform better than guaiac FOBTs; however, the sensitivity and specificity of immunochemical FOBTs remain unsatisfactory. To resolve this problem, novel fecal molecular methods based on fecal protein, DNA and RNA analyses have been developed. Regarding fecal proteins, several marker proteins indicating intestinal bleeding and cancer cell-specific proteins have been investigated. Regarding fecal DNA, numerous gene mutation and gene methylation analyses have been reported. Consequently, fecal DNA analysis was recommended as a CRC screening method in 2008. In addition, gene expression analyses of CRC-specific genes and miRNAs in fecal RNA have been investigated over the last decade. This review article summarizes molecular methods using fecal samples for CRC screening, focusing on reports within the last 5 years.

Fecal miR-106a is a useful marker for colorectal cancer patients with false-negative results in immunochemical fecal occult blood test.

BACKGROUND: Immunochemical fecal occult blood test (iFOBT) is widely used for colorectal cancer screening; however, its sensitivity is insufficient. We recently reported a fecal microRNA (miRNA) test (FmiRT) to detect colorectal cancer. In this study, we investigated a new colorectal cancer screening method combining iFOBT and FmiRT to improve the sensitivity compared with iFOBT alone. METHODS: In total, 117 colorectal cancer patients and 107 healthy volunteers were enrolled. Ten-milligram fecal samples were collected and iFOBT was conducted. Fecal RNA was extracted from residuum of iFOBT and then the expression of 14 kinds of miRNA was analyzed for the FmiRT using real-time reverse transcription PCR. RESULTS: Levels of fecal miR-106a expression in iFOBT+ patients and iFOBT- patients were significantly higher than in healthy volunteers (P = 0.001). The sensitivity and specificity of FmiRT using miR-106a were 34.2% and 97.2%, and those of iFOBT were 60.7% and 98.1%, respectively. The overall sensitivity and specificity of the new screening method combining iFOBT and FmiRT were 70.9% and 96.3%, respectively. One quarter of colorectal cancer patients with false-negative iFOBT seemed to be true positive upon adding FmiRT using fecal miR-106a. CONCLUSIONS: Fecal miR-106a is a good molecular marker to identify colorectal cancer patients from among those with negative iFOBT results. FmiRT combined with iFOBT may improve the sensitivity to detect colorectal cancer. IMPACT: We have shown the usefulness of fecal miR-106a to detect the colorectal cancer patients among those with negative iFOBT results.

Application of the fecal microRNA test to the residuum from the fecal occult blood test.

OBJECTIVE: Though the fecal occult blood test is used for colorectal cancer screening worldwide, it does not have a particularly high sensitivity for detecting colorectal cancer. Here we investigated the applicability of the fecal microRNA test to fecal samples that had been used for a previous fecal occult blood test and stored under various conditions. METHODS: Five colorectal cancer patients and five healthy volunteers were enrolled. Fecal samples were stored for 0-5 days at 4°C, room temperature or 37°C. Total RNA was extracted from the fecal occult blood test residuum and microRNA expression was analyzed by real-time reverse transcription polymerase chain reaction. RESULTS: There were no remarkable differences either in colorectal cancer patients or in controls with regard to the concentration of RNA extracted from the fecal occult blood test residuum in any of the storage groups compared with the samples prepared on day 0 (Group 0). Ribosomal RNA stored at room temperature or 37°C degraded rapidly. In contrast, the ribosomal RNA stored at 4°C remained intact for at least 5 days. The microRNAs in samples stored at 4°C and room temperature were conserved; however, the microRNAs stored at 37°C were significantly degraded compared with Group 0 (P < 0.05). In the residuum stored at 4°C up to 5 days, the relative quantification of miR-106a normalized with miR-24 in colorectal cancer patients was significantly higher than those in healthy volunteers (P < 0.05). In contrast, the quantification of normalized miR-106a was remarkably low in samples stored at room temperature and 37°C. CONCLUSIONS: Fecal microRNA of sufficient quality for reverse transcription polymerase chain reaction analysis was extracted from the fecal occult blood test residuum stored at 4°C for up to 5 days.