Development and evaluation of a master-slave robot system for single-incision laparoscopic surgery

Single-incision laparoscopic surgery (SILS) brings cosmetic benefits for patients, but this procedure is more difficult than laparoscopic surgery. In order to reduce surgeons' burden, we have developed a master-slave robot system which can provide robot-assisted SILS as if it were performing conventional laparoscopic surgery and confirmed the feasibility of our proposed system. The proposed system is composed of an input device (master side), a surgical robot system (slave side), and a control PC. To perform SILS in the same style as regular laparoscopic surgery, input instruments are inserted into multiple incisions, and the tip position and pose of the left-sided (right-sided) robotic instrument on the slave side follow those of the right-sided (left-sided) input instruments on the master side by means of a control command from the PC. To validate the proposed system, we defined four operating conditions and conducted simulation experiments and physical experiments with surgeons under these conditions, then compared the results. In the simulation experiments, we found learning effects between trials (P = 0.00013 0.1), and the task time of our system was significantly shorter than the simulated SILS (P = 0.011 < 0.05). In the physical experiments, our system performed SILS more easily, efficiently, and intuitively than the other operating conditions. Our proposed system enabled the surgeons to perform SILS as if they were operating conventionally with laparoscopic techniques.ArticleINTERNATIONAL JOURNAL OF COMPUTER ASSISTED RADIOLOGY AND SURGERY. 7(2):289-296 (2012)journal articl

Venous Thromboembolism Following Lateral Lymph Node Dissection for Rectal Cancer

Kobayashi Y., Uemura M., Paku M., et al. Venous Thromboembolism Following Lateral Lymph Node Dissection for Rectal Cancer. Anticancer Research 44, 695 (2024); https://doi.org/10.21873/anticanres.16860 .Background/Aim: Postoperative venous thromboembolism (VTE) is a well-recognized complication that leads to morbidity and mortality. Lateral lymph node dissection (LLND) for rectal cancer is thought to potentially increase the risk of VTE due to its technical complexity. However, the relationship between LLND and VTE remains inadequately understood. The aim of this study was to elucidate the impact of LLND on the incidence of postoperative VTE. Patients and Methods: This is a retrospective analysis of patients who underwent rectal cancer resection between 2010 and 2018 to identify the risk factors associated with postoperative VTE. Patients were divided into two groups: those who underwent surgery with LLND (LLND+ group) and those who underwent surgery without LLND (LLND– group). Results: A total of 543 patients were enrolled in this study, and 113 patients underwent surgery for rectal cancer with LLND. VTE developed in 8 patients (1.47%), with the incidence rates being 4.42% in the LLND+ group and 0.69% in the LLND–group, respectively (p=0.012). Three of 8 patients had developed severe postoperative complications, and the other two patients needed intraoperative repair of the iliac vein during LLND procedure. Multivariate analysis identified the incidence of postoperative complications and LLND as the independent risk factors of VTE. Conclusion: Patients undergoing rectal cancer surgery with LLND should be closely monitored for signs of VTE

Oct4 Gene Expression in Primary Colorectal Cancer Promotes Liver Metastasis

Purpose. The Oct4 gene plays an important role in undifferentiated embryonic stem cells and regulates stem cell pluripotency. The aim of this study was to examine the relationship between Oct4 expression and liver metastasis of colorectal cancer (CRC) in clinical samples and investigate the role and abilities of Oct4-positive CRC cells. Methods. The study included 158 patients who underwent surgery for CRC between 2009 and 2011. The correlations between the Oct4 gene expression and the clinical parameters were assessed, and liver metastasis-free survival (LMFS) was evaluated in these patients. Oct4-EGFP-positive cells were established to examine their subpopulation and ability. The capacity to form liver metastasis in vivo was examined using CRC cell lines and primary cultured CRC cells. Results. LMFS was significantly poor in the Oct4 high-expression group compared with the low-expression group (P=0.008). Multivariate analyses showed that Oct4 expression (P=0.015) and TNM stage (P<0.001) were significantly correlated with LMFS. Oct4-EGFP-positive cells highly expressed stem cell-associated markers and had self-renewal and differentiation abilities. Oct4-high cells actively formed liver metastasis. Conclusion. The Oct4 expression was correlated with liver metastasis in CRC patients. Oct4 expression cells have self-renewal and differentiation abilities like those of cancer stem cells. Oct4 contributed to forming liver metastasis in CRC

Effect of lateral body position on transesophageal echocardiography images and the association with patient characteristics: A prospective observational study

Background: Changes in heart position are occasionally observed on the transesophageal echocardiography (TEE) image screen after changing the body position from supine to lateral, although the magnitude of change in cardiac position varies individually. We hypothesized that this variation is associated with certain patient characteristics and evaluated how lateral positioning affects visualization of the heart on TEE and whether the magnitude of change in the heart position correlates with patient characteristics. Methods: Fifty-three lung resection patients were enrolled. Two angle and two length parameters (DqTV , DqAP , DL TV , and DL AP ) were defined to describe location change of the lateral tricuspid annulus and right ventricular apex on the TEE image between supine and lateral position. The correlation coefficients were calculated between these four parameters and patient characteristics, including age, body mass index (BMI), epicardial fat thickness, and pulmonary function variables. Results: The DqTV correlated positively and inversely with BMI in both right and left lateral patients (right: r = 0.6365, P = 0.0034; left: r = −0.6616, P < 0.0001, respectively). In left lateral patients, the DqTV correlated inversely with epicardial fat thickness (r = −0.4879, P = 0.0182), and the DL AP correlated positively with the forced vital capacity percent predicted (r = 0.5736, P = 0.0082). Conclusions: Lateral body positioning affects cardiac visualization on TEE, and the BMI, epicardial fat thickness, and pulmonary function moderate this effect

Triclosan-coated sutures to reduce surgical site infection in abdominal gastrointestinal surgery: A meta-analysis and systematic review

Background: Previous randomized trials evaluated the effectiveness of triclosan-coated sutures for fascial closure in preventing surgical site infection (SSI). However, available evidence remains still inconclusive. We aimed to evaluate the effectiveness of triclosan-coated sutures in fascia closure in preventing postoperative SSI in elective gastrointestinal surgery. Meta-analysis: A meta-analysis included present outcomes, evaluating the advantages of triclosan-coated compared with non-coated sutures in preventing SSIs for fascia closure of laparotomy in abdominal gastrointestinal surgery. To identify prospective randomized trials regarding this topic, we searched Cochrane Central Register of Controlled Trials (Central) and PubMed with the following search terms: “triclosan or triclosan coated;” “surgical site infection;” and “randomized controlled trial” was searched, respectively. To avoid the evaluation of the heterogenous group of patients, the following studies were excluded; only emergency surgery, or not including gastroenterological surgery. The Mantel-Haenszel random-effects model was performed with R software (CRAN, R3·6·2; https://cran.r-project.org/). Results: This meta-analysis included eleven phase-III and two prospective studies, which comprised 9588 patients. The aggregated phase-III results of the trials demonstrate a significant superiority of triclosan-coated sutures compared with non-coated sutures (random-effect model, OR 0.71, 95 % CI 0.56–0.90, P = 0.0052). Conclusion: The meta-analysis showed benefit with triclosan-coated sutures in preventing SSI after gastrointestinal surgery

Targeting cancer stem cells in refractory cancer

Although common cancer therapies, such as chemotherapy and radiation therapy, have recently improved and yielded good results, evaluated as tumor shrinkage, disease recurrence is still a common event for most cancer patients. This is termed refractory cancer. This tumor regrowth following therapy is generally thought to be caused by a small, specific population of tumor cells called cancer stem cells (CSCs). Similar to other stem cells, CSCs have the capacity for self-renewal and multipotent differentiation, and they have been identified in many tumor types based on cell surface protein expression. This specific cell population has stemness characteristics as examined by serial transplantation in animal models. Previous studies have developed a specific signature of cell surface markers and biological functions that can identify CSCs in many solid tumors. In this review, we summarize the characterization of CSCs using new techniques for identifying and quantifying them in situ. These techniques and concepts could be valuable for evaluating the effects of therapies on this cell population. Finally, we conclude by discussing several unique preclinical treatment strategies to targets CSCs, such as reprogramming CSCs or inducing attack by immune cells. Therapeutic and diagnostic methodologies that can target and quantify CSCs will be valuable tools for eradicating refractory cancer