Life prognosis of sentinel node navigation surgery for early-stage gastric cancer:Outcome of lymphatic basin dissection

BACKGROUND Lymphatic basin dissection is a sentinel node biopsy method that is specific for gastric cancer.In this method,the dyed lymphatic system is dissected en bloc,and sentinel nodes are identified at the back table(ex vivo).Even with lymphatic basin dissection,blood flow to the residual stomach can be preserved,and functionpreserving curative gastrectomy can be performed.The oncological safety of function-preserving curative gastrectomy combined with lymphatic basin dissection has not yet been fully investigated.We hypothesized that the oncological safety of sentinel node navigation surgery(SNNS)is not inferior to that of the guidelines.AIM To investigate the life prognosis of SNNS for gastric cancer in comparison with guidelines surgery.METHODS This was a retrospective cohort study.Patients were selected from gastric cancer patients who underwent sentinel node biopsy from April 1999 to March 2016.Patients from April 1999 to August 2008 were from the Department of Surgery II,Kanazawa University Hospital,and patients from August 2009 to March 2016 were from the Department of Surgical Oncology,Kanazawa Medical University Hospital.Patients who were diagnosed with gastric cancer,which was preoperatively diagnosed as superficial type(type 0),5 cm or less in length,clinical T1-2 and node negative,and underwent various gastrectomies guided by sentinel node navigation were retrospectively collected.The overall survival(OS)and relapsefree survival(RFS)of these patients(SNNS group)were investigated.Patients with gastric cancer of the same stage and who underwent guidelines gastrectomy with standard nodal dissection were also selected as the control group.RESULTS A total of 239 patients in the SNNS group and 423 patients in the control group were included.Pathological nodal metastasis was observed in 10.5%and 10.4%of the SNNS and control groups,respectively.The diagnostic abilities of sentinel node biopsy were 84%and 98.6%for sensitivity and accuracy,respectively.In the SNNS group,81.6%of patients underwent modified gastrectomy or functionpreserving curative gastrectomy with lymphatic basin dissection,in which the extent of nodal dissection was further reduced compared to the guidelines.The OS rate in the SNNS group was 96.8%at 5 years and was significantly better than 91.3%in the control group(P=0.0014).The RFS rates were equal in both groups.After propensity score matching,there were 231 patients in both groups,and the cumulative recurrence rate was 0.43%at 5 years in the SNNS group and 1.30%in the control group,which was not statistically different.CONCLUSION The oncological safety of patients who undergo gastrectomy guided by sentinel node navigation is not inferior to that of the guidelines surgery.

The da Vinci Surgical System versus the Radius Surgical System

Objective: Kanazawa University introduced the da Vinci surgical system and the Radius surgical system. In this study, we compared the advantages and disadvantages of each system. Methods: The da Vinci system is a master-slave tele-manipulation system, which provides hi-resolution 3D images. The Radius system is pair of hand-guided surgical manipulators. In this study we focus on the operability of both instruments rather than their 3D optical systems. Results: The Radius was originally developed specifically focused on ligation and suturing with suture sizes bigger than 4-0, it is more effective, less expensive compared with the da Vinci. Although the da Vinci system is bulky, it allows surgeons to perform endoscopic surgeries only if ports are properly placed to prevent each arm from colliding with the other arms. A crucial difference between the Radius and the da Vinci is not limited to anastomose small vessels but is extended to multidirectional dissection. Currently, the cost including initial investment is the biggest issue;however, the da Vinci is absolutely necessary to implement delicate cardiac surgeries endoscopically and less-invasively. Early approval of robotic surgery by the government is urgently required in Japan. Conclusions: Although both the da Vinci and the Radius have endoscopic instruments with a multi-degree of freedom, applications need to be differentiated depending on the procedures and indications. Therefore, it can be clearly said that these unique innovative systems will never compete against each other.

Effectiveness and safety of a laparoscopic training system combined with modified reconstruction techniques for total laparoscopic distal gastrectomy

BACKGROUND Total laparoscopic distal gastrectomy(TLDG)is increasing due to some advantages over open surgery,which has generated interest in gastrointestinal surgeons.However,TLDG is technically demanding especially for lymphadenectomy and gastrointestinal reconstruction.During the course of training,trainee surgeons have less chances to perform open gastrectomy compared with that of senior surgeons.AIM To evaluate an appropriate,efficient and safe laparoscopic training procedures suitable for trainee surgeons.METHODS Ninety-two consecutive patients with gastric cancer who underwent TLDG plus Billroth I reconstruction using an augmented rectangle technique and involving trainees were reviewed.The trainees were taught a laparoscopic view of surgical anatomy,standard operative procedures and practiced essential laparoscopic skills.The TLDG procedure was divided into regional lymph node dissections and gastrointestinal reconstruction for analyzing trainee skills.Early surgical outcomes were compared between trainees and trainers to clarify the feasibility and safety of TLDG performed by trainees.Learning curves were used to assess the utility of our training system.RESULTS Five trainees performed a total of 52 TLDGs(56.5%),while 40 TLDGs were conducted by two trainers(43.5%).Except for depth of invasion and pathologic stage,there were no differences in clinicopathological characteristics.Trainers performed more D2 gastrectomies than trainees.The total operation time was significantly longer in the trainee group.The time spent during the lesser curvature lymph node dissection and the Billroth I reconstruction were similar between the two groups.No difference was found in postoperative complications between the two groups.The learning curve of the trainees plateaued after five TLDG cases.CONCLUSION Preparing trainees with a laparoscopic view of surgical anatomy,standard operative procedures and practice in essential laparoscopic skills enabled trainees to perform TLDG safely and feasibly.

Open Distal Gastrectomy versus Laparoscopic Distal Gastrectomy: As Influenced by Facility Background Factors in the Real World

The purpose of our study was to retrospectively evaluate the clinical efficacy and safety of laparoscopy assisted distal gastrectomy (LADG) performed by one operating and advising surgeon in patients with gastric cancer over a period of 10 years. We examined the choice of anastomosis techniques, and compared the duration of surgery, blood loss, number of dissected lymph nodes and intraoperative complications for LADG and open distal gastrectomy (ODG). We studied 254 patients who underwent laparoscopic gastrectomy and 36 patients who underwent ODG. 169 of 254 patients received LADG. Duration of surgery was significantly longer for LADG than that for ODG, blood loss was significantly smaller, and numbers of dissected lymph nodes were similar. With LADG, there was anastomotic leakage in 2 patients and postoperative obstruction in 2 patients. No recurrence of disease and no deaths have been reported to date. Though previous clinical trials have shown that LADG is less invasive, our study of LADG in the real world did not show superiority, but rather equivalence to ODG in terms of other outcomes. This study could be advantageous to evaluate the clinical efficacy and safety of LADG without having to take into account multiple surgeons’ technical levels and the background differences between the facilities.