Taro Oshikiri

CD8+ tumor-infiltrating lymphocytes together with CD4+ tumor-infiltrating lymphocytes and dendritic cells improve the prognosis of patients with pancreatic adenocarcinoma.

Objective Recent studies have demonstrated the importance of tumor immunity for a cancer patients prognosis. In some types of cancer, it has been shown through immunohistochemical analysis that the existence of CD8+ tumor-infiltrating lymphocytes (TILs) is a crucial factor in determining prognosis. In an experimental model, CD4+ lymphocytes together with CD8+ lymphocytes contributed significantly to tumor immunity. Methods Specimens were taken from 80 surgically resected pancreatic adenocarcinomas between 1992 and 1999. Immunohistochemical staining of CD4, CD8, and S100 protein was performed, and the levels of these proteins were determined by microscopic analysis. The percentages of patients in the CD4(+) and CD8(+) groups were 59% (47/80) and 25% (16/80), respectively. When separated into 4 groups, CD4/8(+/+), CD4/8(+/−), CD4/8(−/+) and CD4/8(−/−), the overall survival rate was significantly higher in CD4/8(+/+) patients (13 cases) compared with those in all other groups combined (67 cases; P = 0.0098). CD4/8(+/+) status was negatively correlated with tumor depth and TNM stage. Multivariate analyses showed that CD4/8(+/+) status was an independent favorable prognostic factor. The number of tumor-infiltrating S100 protein positive cells was also significantly higher in the CD4/8(+/+) group than in others (P = 0.0084). Conclusions In pancreatic adenocarcinoma, the presence of CD4+ TILs together with CD8+ TILs serves as a good indicator of the patients outcome after surgical treatment.

Preoperative sarcopenia is a predictor of postoperative pulmonary complications in esophageal cancer following esophagectomy: A retrospective cohort study

OBJECTIVES The number of geriatric patients with esophageal cancer has been increasing. Geriatric syndromes such as sarcopenia might adversely affect postoperative recovery. The aim of this study was to evaluate the relationships between sarcopenia and postoperative complications, and the associations between sarcopenia and perioperative functional changes in patients with esophageal cancer following esophagectomy. MATERIALS AND METHODS Participants comprised 104 patients who underwent esophagectomy from July 2011 to April 2015. Preoperative sarcopenia was diagnosed by the presence of low muscle mass and low physical functions according to Asian Working Group for Sarcopenia criteria. Low physical function was defined by loss of grip strength and/or slow walking speed. Postoperative pulmonary, cardiac, infectious, and surgical complications were extracted. Perioperative functional changes were calculated (value at postoperative day 30-value before surgery). For statistical analyses, both uni- and multivariate logistic regression analyses were performed. RESULTS Twenty-nine patients (27.9%) were diagnosed with sarcopenia. The incidence of postoperative pulmonary complications was significantly higher in the sarcopenia group (37.9%) than in the non-sarcopenia group (17.3%; P=0.04). There was no relationship between sarcopenia and other complications or perioperative functional changes. Multivariate analysis identified sarcopenia (odds ratio (OR), 3.13; 95% confidence interval (CI), 1.12-8.93) and high Brinkman index (OR, 3.46; 95% CI, 1.20-11.77) as independent risk factors for the development of pulmonary complications. CONCLUSION The assessment of sarcopenia may be useful to predict the postoperative pulmonary complications following esophagectomy. On the other hand, sarcopenia does not predict cardiac, infectious, and surgical complications or perioperative function.

Laparoscopic complete mesocolic excision for right-sided colon cancer using a cranial approach: anatomical and embryological consideration

BackgroundComplete mesocolic excision (CME) with central vascular ligation (CVL) should be employed for the treatment of colon cancer patients because of its superior oncological outcomes. However, this technique is technically challenging in laparoscopic right hemicolectomy because of the anatomical complexity of the transverse mesocolon.MethodsWe focused on the embryology and anatomy of the transverse mesocolon to overcome the difficulty of this surgery. The validity and efficacy of a cranial approach in achieving CME with CVL in laparoscopic right hemicolectomy was elucidated from the embryological point of view.ResultsIn total, 28 consecutive patients with right-sided colon cancer were treated by laparoscopic right hemicolectomy using a cranial approach. There were no conversion to open surgery or switching to another approach. Using this approach, torsion and fusion of the transverse mesocolon, which occurred during embryological development, could be reversed and the complex anatomy of the transverse mesocolon could be simplified before performing CVL of colonic vessels.ConclusionsA cranial approach is considered valid and useful for CME with CVL in laparoscopic right hemicolectomy from the embryological point of view.

Prone position in thoracoscopic esophagectomy improves postoperative oxygenation and reduces pulmonary complications.

BackgroundWhile thoracoscopic esophagectomy is a widely performed surgical procedure, only few studies regarding the influence of body position on changes in circulation and breathing, after the surgery, have been reported. This study aimed at evaluating the effect of body position, during surgery, on the postoperative breathing functions of the chest.MethodsA total of 266 patients who underwent right-sided transthoracic esophagectomy for esophageal cancer from 2004 to 2012 were included in this study. Fifty-four of them underwent open thoracotomies in the left lateral decubitus position (Group O), 108 underwent thoracoscopic esophagectomy in the left lateral decubitus position (Group L) and 104 patients were treated by thoracoscopic esophagectomy in the prone position (Group P). Two patients in Group P, who presented with intra-operative bleeding and underwent thoracotomy, were subsequently excluded from the pulmonary function analysis.ResultsTwo patients in Group P had to be changed from the prone position to the lateral decubitus position and underwent thoracotomy in order to control intra-operative bleeding. Despite the significantly longer chest operation period in Group P, total blood loss was significantly lower in this group when compared to Groups O and L. Furthermore, patients in Group P presented with significantly lower water balance during the perioperative period and markedly higher SpO2/FiO2 ratio after the surgery. The incidence of respiratory complications was significantly higher in Group O when compared to the other two groups; however, no significant differences were observed between the Groups L and P.ConclusionThe findings of this study demonstrate that thoracoscopic esophagectomy in the prone position improves postoperative oxygenation and is therefore a potentially superior surgical approach.

The learning effect of using stereoscopic vision in the early phase of laparoscopic surgical training for novices

BackgroundRecently to improve depth perception, the performance of three-dimensional (3D) laparoscopic surgeries has increased. However, the effects of laparoscopic training using 3D are still unclear. This study aimed to clarify the effects of using a 3D monitor among novices in the early phase of training.MethodsParticipants were 40 novices who had never performed laparoscopic surgery (20 medical students and 20 junior residents). Three laparoscopic phantom tasks (task 1: touching markers on a flat disk with a rod; task 2: straight rod transfer through a single loop; and task 3: curved rod transfer through two loops) in the training box were performed ten times, respectively. Performances were recorded by an optical position tracker. The participants were randomly divided into two groups: one group performed each task five times initially under a 2D system (2D start group), and the other group performed each task five times under a 3D system (3D start group). Both groups then performed the same task five times. After the trial, we evaluated the performance scores (operative time, path length of forceps, and technical errors) and the learning curves for both groups.ResultsScores for all tasks performed under the 3D system were significantly better than scores for tasks using the 2D system. Scores for each task in the 2D start group improved after switching to the 3D system. However, scores for each task in the 3D start group were worse after switching to the 2D system, especially scores related to technical errors.ConclusionsThe stereoscopic vision improved laparoscopic surgical techniques of novices from the early phase of training. However, the performance of novices trained only by 3D worsened by changing to the 2D environment.

Outcomes and prognostic factors of selective lateral pelvic lymph node dissection with preoperative chemoradiotherapy for locally advanced rectal cancer

PurposeThe clinical significance of preoperative chemoradiotherapy (CRT) and lateral lymph node dissection (LLND) for locally advanced rectal cancer remains unclear. We have employed total mesorectal excision and selective LLND following preoperative CRT for patients with locally advanced rectal cancer. The validity of our strategy was evaluated.MethodsA total of 45 patients with locally advanced rectal cancer who underwent curative surgery after CRT from November 2005 to September 2016 were retrospectively analyzed. LLND was performed only for the patients with lateral lymph nodes suspected to have metastasis based on the pretreatment images.ResultsRates of 5-year overall survival (OS) and 5-year relapse-free survival (RFS) were 85.7 and 61.8%, respectively. Univariate and multivariate analyses detected only histological response (grades 2 and 3 vs. grade 1) as a significant prognostic factor for OS and local recurrence. ypN and ypStage were significant factors for RFS by univariate analysis, while no significant factor was detected by multivariate analysis. There was no significant factor for distant recurrence. In good responders (grades 2 and 3), the local recurrence rate was 0% (P = 0.006, vs. grade 1), while distant recurrence developed in 4 of 20 cases (20%, P = 0.615, vs. grade 1). There was no local recurrence in LLND (−) group regardless the histological response.ConclusionsAlthough selective LLND with preoperative CRT seems effective and valid for good responders, new treatment strategy is necessary for poor responders. Therefore, development of reliable biomarkers for histological response to CRT is an urgent need.

Quantitative comparison of operative skill using 2- and 3-dimensional monitors during laparoscopic phantom tasks

Background. The recent development of stereoscopic images using 3‐dimensional monitors is expected to improve techniques for laparoscopic operation. Several studies have reported technical advantages in using 3‐dimensional monitors with regard to operative accuracy and working speed, but there are few reports that analyze forceps motions by 3‐dimensional optical tracking systems during standardized laparoscopic phantom tasks. We attempted to develop a 3‐dimensional motion analysis system for assessing laparoscopic tasks and to clarify the efficacy of using stereoscopic images from a 3‐dimensional monitor to track forceps movement during laparoscopy. Methods. Twenty surgeons performed 3 tasks (Task 1: a simple operation by the dominant hand, Task 2: a simple operation using both hands, Task 3: a complicated operation using both hands) under 2‐dimensional and 3‐dimensional systems. We tracked and recorded the motion of forceps tips with an optical marker captured by a 3‐dimensional position tracker. We analyzed factors such as forceps path lengths, operation times, and technical errors for each task and compared the results of 2‐dimensional and 3‐dimensional monitors. Results. Mean operation times and technical errors were improved significantly for all tasks performed under the 3‐dimensional system compared with the 2‐dimensional system; in addition, mean path lengths for the forceps tips were shorter for all tasks performed under the 3‐dimensional system. Conclusion. We found that stereoscopic images using a 3‐dimensional monitor improved operative techniques with regard to increased accuracy and shorter path lengths for forceps movement, which resulted in a shorter operation time for basic phantom laparoscopic tasks.

Conservative reconstruction using stents as salvage therapy for disruption of esophago-gastric anastomosis

Esophagectomy with extended lymphadenectomy and gastric conduit reconstruction is a radical procedure for the treatment of esophageal cancer that is associated with a high morbidity rate. Gastric conduit necrosis is a fatal complication that occurs in 2% of patients. Conventionally, two-stage salvage surgery consisting of removal of the necrotic gastric conduit followed by reconstruction has been performed; however, this procedure has a high morbidity rate. We describe a 61-year-old man who underwent minimally invasive esophagectomy complicated by slowly progressive gastric conduit necrosis associated with complete neck drainage and a stable overall condition. There was a 2 cm gap in the anastomosis. Because there was no evidence of residual gastric conduit necrosis, a removable, covered self-expanding metal stent (SEMS) was inserted to bridge the anastomosis. The stent was fixed to the patients ear with silk thread through the lasso on its proximal end to prevent migration. Eight weeks after insertion, the stent was removed easily without any associated complications. The anastomotic defect was completely bridged with granulation tissue, showing progressive epithelialization without leakage or stenosis. The patient was discharged home in good general health. This is the first report of the successful conservative management of esophago-gastric conduit anastomosis disruption with SEMS placement.

The effect on surgical skills of expert surgeons using 3D/HD and 2D/4K resolution monitors in laparoscopic phantom tasks

BackgroundRecently, several new imaging technologies, such as three-dimensional (3D)/high-definition (HD) stereovision and high-resolution two-dimensional (2D)/4K monitors, have been introduced in laparoscopic surgery. However, it is still unclear whether these technologies actually improve surgical performance.MethodsParticipants were 11 expert laparoscopic surgeons. We designed three laparoscopic suturing tasks (task 1: simple suturing, task 2: knotting thread in a small box, and task 3: suturing in a narrow space) in training boxes. Performances were recorded by an optical position tracker. All participants first performed each task five times consecutively using a conventional 2D/HD monitor. Then they were randomly divided into two groups: six participants performed the tasks using 3D/HD before using 2D/4K; the other five participants performed the tasks using a 2D/4K monitor before the 3D/HD monitor. After the trials, we evaluated the performance scores (operative time, path length of forceps, and technical errors) and compared performance scores across all monitors.ResultsSurgical performances of participants were ranked in decreasing order: 3D/HD, 2D/4K, and 2D/HD using the total scores for each task. In task 1 (simple suturing), some surgical performances using 3D/HD were significantly better than those using 2D/4K (P = 0.017, P = 0.033, P = 0.492 for operative time, path length, and technical errors, respectively). On the other hand, with operation in narrow spaces such as in tasks 2 and 3, performances using 2D/4K were not inferior to 3D/HD performances. The high-resolution images from the 2D/4K monitor may enhance depth perception in narrow spaces and may complement stereoscopic vision almost as well as using 3D/HD.ConclusionsCompared to a 2D/HD monitor, a 3D/HD monitor improved the laparoscopic surgical technique of expert surgeons more than a 2D/4K monitor. However, the advantage of 2D/4K high-resolution images may be comparable to a 3D/HD monitor especially in narrow spaces.

Recent updates in perioperative chemotherapy and recurrence pattern of gastric cancer

Gastrectomy with D2 lymph node dissection has become the global standard procedure for locally advanced gastric cancer to maximally reduce locoregional recurrence. In East Asia, based on the evidence of the ACTS‐GC and the CLASSIC trials, postadjuvant chemotherapy with S‐1 monotherapy or capecitabine and oxaliplatin after curative D2 gastrectomy is the current standard strategy. However, approximately 20% to 30% of patients still develop distant recurrence even after these postadjuvant chemotherapies, especially in those with pathological stage III disease. This review summarizes recent (2008‐2018) evidence on the benefits of adjuvant therapy for locally advanced gastric cancer. JACRO GC‐07, a Phase III trial, recently showed a superior 3‐year recurrence‐free survival of the S‐1 plus docetaxel regimen in comparison to S‐1 monotherapy for patients with pathological stage III gastric cancer after curative D2 gastrectomy. With regard to recent new evidence on neoadjuvant strategy, JCOG0501, a Phase III trial, did not show any superiority in 3‐year overall survival (OS) of additional neoadjuvant chemotherapy with S‐1/cisplatin over postadjuvant S‐1 monotherapy in scirrhous type gastric cancer. Further clinical trials of neoadjuvant chemotherapy are ongoing to improve the poor prognosis for gastric cancer with extensive lymph node metastases. These trials could lead to new evidence for improved treatment of gastric cancer in the near future.