Robotic surgery for upper gastrointestinal cancer: Current status and future perspectives

Robotic surgery with the da Vinci Surgical System has been increasingly applied in a wide range of surgical specialties, especially in urology and gynecology. However, in the field of upper gastrointestinal (GI) tract, the da Vinci Surgical System has yet to be standard as a result of a lack of clear benefits in comparison with conventional minimally invasive surgery. We have been carrying out robotic gastrectomy and esophagectomy for operable patients with resectable upper GI malignancies since 2009, and have demonstrated the potential advantages of the use of the robot in possibly reducing postoperative local complications including pancreatic fistula following gastrectomy and recurrent laryngeal nerve palsy after esophagectomy, even though there have been a couple of problems to be solved including longer duration of operation and higher cost. The present review provides updates on robotic surgery for gastric and esophageal cancer based on our experience and review of the literature.

Delta-shaped anastomosis in totally robotic Billroth I gastrectomy: technical aspects and short-term outcomes

INTRODUCTION

Delta-shaped anastomosis has been recognized as a method of intracorporeal Billroth I anastomosis in totally laparoscopic distal gastrectomy. However, the technical aspects and outcomes of the delta-shaped anastomosis in totally robotic distal gastrectomy have never been reported.

METHODS

A single-institutional, non-randomized, retrospective study was performed between 2009 and 2013. During the study period, 47 patients underwent robotic distal gastrectomy followed by robotic delta-shaped Billroth I reconstruction, and 165 patients underwent conventional laparoscopic distal gastrectomy followed by laparoscopic delta-shaped Billroth I reconstruction. After 64 were excluded because of insufficient intraoperative video, 43 patients in the robotic group and 105 patients in the laparoscopic group were enrolled in the study. Short-term outcomes were determined from medical records and full-length operative videos.

RESULTS

There were no significant differences between the robotic and laparoscopic groups in terms of morbidity (4.7% vs 3.8%), anastomosis-related complications (0% vs 1.0%), non-anastomosis-related complications (2.3% vs 0%), or systemic complications (2.3% vs 0%). Time for reconstruction did not vary between the robotic group (16.6 min [8.8-42.9 min]) and the laparoscopic group (15.8 min [7.2-41.0 min]). There was no mortality in this series. In the conventional group, the morbidity rate was 3.8%. The anastomosis-related complication rate was 1.0% in the conventional group.

CONCLUSIONS

Given the excellent short-term outcomes related to anastomosis, delta-shaped anastomosis after robotic distal gastrectomy was at least as feasible and safe as delta-shaped anastomosis after laparoscopic distal gastrectomy.

An innovative masticatory efficiency test using odour intensity in the mouth as a target marker: a feasibility study

A large number of studies have reported the findings for masticatory efficiency tests; however, some objective masticatory efficiency tests have a drawback, in that subjects are required to spit out the test material. This study examined the possibility of a masticatory efficiency test that evaluates the intensity of odours released when chewing an odour compound-containing material. A total of 20 volunteers were used in this study. The odour intensity in the breath after chewing a gum was measured by portable odour sensor device. The odour intensity after chewing the gum was measured over four chewing durations and at four intervals between spitting out and measurement of the odour intensity. The volume of stimulated saliva was measured by calculating the difference in the weight of the gauze before and after chewing to examine the effect of saliva flow. With an increase in chewing duration, odour intensity reduced. The odour intensity was the highest immediately after chewing. There was a positive correlation between odour intensity and gummy jelly-related masticatory efficiency test value (G-METV), which was significant for 10-s chewing. The regression equation was calculated from three objective variables of odour intensity and G-METV as dependent variable. Pearson's correlation coefficient between G-METV and the odour intensity-related masticatory efficiency value (O-METV) was 0·68. The coefficient of variation of O-METV was significantly lower than that of G-METV. These results suggest that the masticatory performance can be estimated by measuring the odour intensity immediately after chewing food containing odour compounds for 10 s.

Posterior layer advancement of lower eyelid retractors with transcanthal canthopexy for involutional lower eyelid entropion

PurposeThe purpose of this study was to examine the surgical outcome of posterior layer advancement of the lower eyelid retractors (LER) with transcanthal canthopexy for involutional lower eyelid entropion.Patients and methodsFifty-one eyelids of 41 patients with involutional entropion and vertical and horizontal laxities that underwent posterior layer advancement of the LER with transcanthal canthopexy were retrospectively reviewed. As a control, we also reviewed previously reported data from 47 entropic eyelids of 37 patients with vertical and horizontal laxities that were successfully corrected using LER advancement and a lateral tarsal strip procedure. Surgical success was defined as the normal eyelid position without contact of any cilia to the globe at the last follow-up examination.ResultsAll eyelids in the present study group were judged as successfully treated without recurrence after 13.9±9.2 months of follow up (mean±SD). The surgical time in the present study group (22.4±5.5 min) was significantly shorter than that in the control group (mean 31.3±4.9 min; P<0.001; Student's t-test). None of the patients showed lateral canthal deformity after surgery.ConclusionsPosterior layer advancement of the LER with transcanthal canthopexy provided complete surgical success with shorter surgical time without the risk of lateral canthal deformity. Posterior layer advancement of the LER with transcanthal canthopexy can be an option for correction of involutional lower eyelid entropion in patients with both vertical and horizontal laxities.

Evaluation of the recurrence pattern of gastric cancer after laparoscopic gastrectomy with D2 lymphadenectomy

Background

The aim of this study was to analyze the oncological aspects of gastric cancer following laparoscopic gastrectomy with D2 lymphadenectomy (LG-D2).

Methods

We retrospectively evaluated the long-term outcomes of 354 patients who underwent LG-D2 for primary gastric cancer. Recurrence patterns and predictors of peritoneal metastasis were analyzed.

Results

Median follow-up time was 43.8 months. Five-year overall survival rates for yp/pStages I, II, and III gastric cancer were 93.7, 78.5, and 42.2 %, respectively. Recurrence was observed in 86 patients. Peritoneal metastasis was the most frequent recurrence pattern (n = 51), followed by hepatic metastasis (n = 17). Lymphatic recurrence at distant sites was observed in 10 patients. No locoregional lymph node metastasis or local recurrence was seen. Nine of 51 cases of peritoneal recurrence were detected by probe laparoscopy. Peritoneal recurrence rates were significantly higher in yp/pT4 and yp/pN3 diseases compared with yp/pT ≤ 3 and yp/pN ≤ 2 diseases. Multivariate analyses demonstrated that yp/pT4, yp/pN3, tumor size ≥70 mm, vascular invasion, and undifferentiated tumors were predictors of peritoneal recurrence following LG-D2.

Conclusion

Long-term outcomes of gastric cancer following LG-D2, including recurrence patterns and predictors of peritoneal metastasis, were comparable to those following open D2 gastrectomy. LG-D2 showed good local control. Probe laparoscopy after LG may be effective in detecting peritoneal recurrence, which is not determined with less invasive examinations, including a CT scan. Future large-scale prospective studies are desirable to evaluate not only surgical but also oncological benefits and safety of LG-D2 for advanced gastric cancer.

Effectiveness of laparoscopic stomach-partitioning gastrojejunostomy for patients with gastric outlet obstruction caused by advanced gastric cancer

BACKGROUND

Distal advanced gastric cancer (AGC) occasionally causes gastric outlet obstruction (GOO). We developed a laparoscopic stomach-partitioning gastrojejunostomy (LSPGJ) to restore the ability of food intake.

METHODS

This was a retrospective study performed at a single institution. Of consecutive 78 patients with GOO caused by AGC between 2006 and 2012, 43 patients who underwent LSPGJ were enrolled. The procedure was performed in an antiperistaltic Billroth II fashion, and the afferent loop was elevated and fixed along the staple line of the proximal partitioned stomach. Then, patients for whom R0 resection was planned received chemotherapy prior to laparoscopic gastrectomy. The primary end point was food intake at the time of discharge, which was evaluated using the GOO scoring system (GOOSS). Short- and long-term outcomes were assessed as secondary end points. Overall survival was estimated and compared between the groups who received neoadjuvant chemotherapy followed by surgery (NAC group), definitive chemotherapy followed by curative resection (Conversion group), and best supportive care (BSC group).

RESULTS

The median operative time was 92 min, blood loss did not exceed 30 g in any patient, and postoperative complications (Clavien-Dindo grade ≥2) were only seen in four patients (9.3 %). The median time to food intake was 3 days, and GOOSS scores were significantly improved in 41 patients (95.3 %). Chemotherapy was administered to 38 patients (88.4 %), of whom 11 later underwent radical resection, and 4 of 11 patients underwent conversion surgery following definitive chemotherapy. Median survival times were significantly superior in the NAC (n = 7; 46.8 months) and Conversion (n = 4; 35.9 months) groups than in the BSC group (n = 26; 12.2 months); however, the difference was not significant between the Conversion and NAC groups.

CONCLUSIONS

LSPGJ is a feasible and safe minimally invasive induction surgery for patients with GOO from surgical and oncological perspectives.

Minimally invasive surgery for upper gastrointestinal cancer: Our experience and review of the literature

Minimally invasive surgery (MIS) for upper gastrointestinal (GI) cancer, characterized by minimal access, has been increasingly performed worldwide. It not only results in better cosmetic outcomes, but also reduces intraoperative blood loss and postoperative pain, leading to faster recovery; however, endoscopically enhanced anatomy and improved hemostasis via positive intracorporeal pressure generated by CO2 insufflation have not contributed to reduction in early postoperative complications or improvement in long-term outcomes. Since 1995, we have been actively using MIS for operable patients with resectable upper GI cancer and have developed stable and robust methodology in conducting totally laparoscopic gastrectomy for advanced gastric cancer and prone thoracoscopic esophagectomy for esophageal cancer using novel technology including da Vinci Surgical System (DVSS). We have recently demonstrated that use of DVSS might reduce postoperative local complications including pancreatic fistula after gastrectomy and recurrent laryngeal nerve palsy after esophagectomy. In this article, we present the current status and future perspectives on MIS for gastric and esophageal cancer based on our experience and a review of the literature.

Comparison of the long-term outcomes of robotic radical gastrectomy for gastric cancer and conventional laparoscopic approach: a single institutional retrospective cohort study

BACKGROUND

Robotic gastrectomy (RG) for gastric cancer (GC) has been increasingly performed over the last decade. The technical feasibility and safety of RG for GC, predominantly early GC, have previously been reported; however, few studies have evaluated the oncological outcomes. This study aimed to determine the long-term outcomes of RG for GC compared with those of conventional laparoscopic gastrectomy (LG).

METHODS

Of the 521 consecutive patients with GC who underwent radical gastrectomy at our institution between 2009 and 2012, 84 consecutive patients who underwent RG and 437 patients who received LG were enrolled in this study. Long-term outcomes including the 3-year overall survival (3yOS) and 3-year recurrence-free survival rates (3yRFS) were examined retrospectively.

RESULTS

In the RG group, the 3yOS rates stratified by pathological stage according to the Japanese classification of gastric carcinoma (IA, IB, II, and III) were 94.7, 90.9, 89.5, and 62.5 %, respectively. No differences in 3yOS (RG, 86.9 % vs. LG, 88.8 %; p = 0.636) or 3yRFS (RG, 86.9 % vs. LG, 86.3 %; p = 0.905) were observed between the groups. 3yOS was strongly associated with cancer recurrence within 3 years (p < 0.001), while 3yRFS was associated with tumor size ≥ 30 mm (p < 0.001), clinical stage ≥ IB (p < 0.001), estimated blood loss ≥ 50 mL (p = 0.033), and postoperative pancreatic fistula CD grade ≥ III) (p = 0.035).

CONCLUSIONS

RG for GC was feasible and safe from the oncological point of view in a cohort including a considerable number of patients with advanced GC.

A multi-centre retrospective study of mandibular fractures: do occlusal support and the mandibular third molar affect mandibular angle and condylar fractures?

This retrospective study was performed to investigate the influence of occlusal support and the presence, state, and position of mandibular third molars on the incidence of mandibular angle and condylar fractures. The following variables were investigated: age, sex, cause of fracture, presence and state (impaction, angulation, and the number of roots) of the mandibular third molars, site of the mandibular fracture, presence of occlusal support, duration of intermaxillary fixation, and postoperative complications. Various risk factors for mandibular angle and condylar fractures were investigated by univariate analysis. The risk of mandibular angle fracture was significantly higher in patients with occlusal support and mandibular third molars. The risk of condylar fracture was significantly higher in patients without occlusal support or mandibular third molars. The position and angulation of the mandibular third molars were not significant risk factors in mandibular angle and condylar fractures. This study demonstrated the influence of occlusal support and the presence of mandibular third molars on the incidence of mandibular angle and condylar fractures. The presence of occlusal support may be a more important factor affecting mandibular angle or condylar fractures than the position of the mandibular third molars.

Quasi-particles ultrafastly releasing kink bosons to form Fermi arcs in a cuprate superconductor

In a conventional framework, superconductivity is lost at a critical temperature (T_c) because, at higher temperatures, gluing bosons can no longer bind two electrons into a Cooper pair. In high-T_c cuprates, it is still unknown how superconductivity vanishes at T_c. We provide evidence that the so-called ≲70-meV kink bosons that dress the quasi-particle excitations are playing a key role in the loss of superconductivity in a cuprate. We irradiated a 170-fs laser pulse on Bi₂Sr₂CaCu₂O_8+δ and monitored the responses of the superconducting gap and dressed quasi-particles by time- and angle-resolved photoemission spectroscopy. We observe an ultrafast loss of superconducting gap near the d-wave node, or light-induced Fermi arcs, which is accompanied by spectral broadenings and weight redistributions occurring within the kink binding energy. We discuss that the underlying mechanism of the spectral broadening that induce the Fermi arc is the undressing of quasi-particles from the kink bosons. The loss mechanism is beyond the conventional framework, and can accept the unconventional phenomena such as the signatures of Cooper pairs remaining at temperatures above T_c.

Technical aspects and short- and long-term outcomes of totally laparoscopic total gastrectomy for advanced gastric cancer: a single-institution retrospective study

BACKGROUND

D2 total gastrectomy combined with splenectomy or pancreaticosplenectomy reportedly increases morbidity and mortality. Totally laparoscopic total gastrectomy (TLTG) for advanced gastric cancer (AGC) remains controversial because of its technical difficulties and lack of long-term results. We determined the feasibility and safety of TLTG for AGC.

METHODS

A single-institution retrospective study was conducted. Ninety-two consecutive AGC patients who underwent radical TLTG were enrolled. The primary end point was morbidity. The patients were observed for 3 years following TLTG. We assessed short-term surgical and long-term outcomes, including 3-year overall survival rates (3yOS) and 3-year recurrence-free survival rates (3yRFS).

RESULTS

Early and late morbidities (Clavien-Dindo grade ≥3) were 26.1 and 6.5 %, respectively. Operative time, estimated blood loss, number of dissected lymph nodes, and postoperative hospital stay were 444 (278-694) min, 100 (0-2267) g, 48 (16-89), and 23 (9-136) days, respectively, and 3yOS and 3yRFS rates were 70.7 and 60.9 %, respectively. Factors associated with postoperative complications and 3yOS were operative time [OR 1.011 (1.006-1.017), p < 0.01] and cancer recurrence within 3 years [HR 312.191 (1.126-86573.245], p = 0.045], respectively. 3yRFS was associated with tumor size (≥50 mm) [HR 10.325 (1.328-80.289), p = 0.026], pathological N factor ≥2 [HR 3.188 (1.196-8.495), p = 0.02], and postoperative pancreatic fistula combined with intra-abdominal abscesses Clavien-Dindo grade ≥2; [HR 3.670 (1.440-9.351), p = 0.006].

CONCLUSIONS

TLTG for AGC is sufficiently feasible and safe from both surgical and oncological point of view.

Temperature Dependence of Magnetically Active Charge Excitations in Magnetite across the Verwey Transition

We study the electronic structure of bulk single crystals and epitaxial films of Fe_{3}O_{4}. Fe 2p core level spectra show clear differences between hard x-ray (HAX) and soft x-ray photoemission spectroscopy (PES). The bulk-sensitive spectra exhibit temperature (T) dependence across the Verwey transition, which is missing in the surface-sensitive spectra. By using an extended impurity Anderson full-multiplet model-and in contrast to an earlier peak assignment-we show that the two distinct Fe species (A and B site) and the charge modulation at the B site are responsible for the newly found double peaks in the main peak above T_{V} and its T-dependent evolution. The Fe 2p HAXPES spectra show a clear magnetic circular dichroism (MCD) in the metallic phase of magnetized 100-nm-thick films. The model calculations also reproduce the MCD and identify the contributions from magnetically distinct A and B sites. Valence band HAXPES shows a finite density of states at E_{F} for the polaronic half metal with a remnant order above T_{V} and a clear gap formation below T_{V}. The results indicate that the Verwey transition is driven by changes in the strongly correlated and magnetically active B-site electronic states, consistent with resistivity and optical spectra.

Quadratic Fermi node in a 3D strongly correlated semimetal

Strong spin–orbit coupling fosters exotic electronic states such as topological insulators and superconductors, but the combination of strong spin–orbit and strong electron–electron interactions is just beginning to be understood. Central to this emerging area are the 5d transition metal iridium oxides. Here, in the pyrochlore iridate Pr₂Ir₂O₇, we identify a non-trivial state with a single-point Fermi node protected by cubic and time-reversal symmetries, using a combination of angle-resolved photoemission spectroscopy and first-principles calculations. Owing to its quadratic dispersion, the unique coincidence of four degenerate states at the Fermi energy, and strong Coulomb interactions, non-Fermi liquid behaviour is predicted, for which we observe some evidence. Our discovery implies that Pr₂Ir₂O₇ is a parent state that can be manipulated to produce other strongly correlated topological phases, such as topological Mott insulator, Weyl semimetal, and quantum spin and anomalous Hall states.

5d transition metal iridates provide a platform to study the combined effects of strong spin orbit coupling and strong electronic correlations. Here, the authors find a quadratic band touching in the band structure of Pr₂Ir₂O₇, suggesting it may be tuned to form various strongly correlated topological phases.

The 5-HT3 receptor is essential for exercise-induced hippocampal neurogenesis and antidepressant effects

Exercise has a variety of beneficial effects on brain structure and function, such as hippocampal neurogenesis, mood and memory. Previous studies have shown that exercise enhances hippocampal neurogenesis, induces antidepressant effects and improves learning behavior. Brain serotonin (5-hydroxytryptamine, 5-HT) levels increase following exercise, and the 5-HT system has been suggested to have an important role in these exercise-induced neuronal effects. However, the precise mechanism remains unclear. In this study, analysis of the 5-HT type 3A receptor subunit-deficient (htr3a(-/-)) mice revealed that lack of the 5-HT type 3 (5-HT3) receptor resulted in loss of exercise-induced hippocampal neurogenesis and antidepressant effects, but not of learning enhancement. Furthermore, stimulation of the 5-HT3 receptor promoted neurogenesis. These findings demonstrate that the 5-HT3 receptor is the critical target of 5-HT action in the brain following exercise, and is indispensable for hippocampal neurogenesis and antidepressant effects induced by exercise. This is the first report of a pivotal 5-HT receptor subtype that has a fundamental role in exercise-induced morphological changes and psychological effects.

[UPPER GASTROINTESTINAL SURGERY ON THE ESOPHAGUS AND STOMACH]

In recent years, the number of facilities performing endoscopic surgeries, i.e., thoracoscopic and laparoscopic surgery, of the upper gastrointestinal tract has increased. Endoscopic surgery has many advantages, such as magnification effects, good lighting, and a wide field of view in deep, narrow spaces. On the other hand, there are some technical difficulties in performing endoscopic procedures as in conventional open surgeries. Compared with endoscopic surgery, robotic surgery may facilitate more accurate, safer operations. The da Vinci Surgical System is a high-quality robotic system used for endoscopic surgeries, which offers a three-dimensional view, more degrees of freedom of the instruments, a tremor-filtering system, etc. However, in the absence of adequate operator skill and knowledge, the system cannot provide substantial improvements in the surgical technique. Endoscopic and robotic surgery must be used to offer treatment to patients which is at least equivalent to conventional surgery.

Point nodes persisting far beyond Tc in Bi2212

In contrast to a complex feature of antinodal state, suffering from competing orders, the pairing gap of cuprates is obtained in the nodal region, which therefore holds the key to the superconducting mechanism. One of the biggest question is whether the point nodal state as a hallmark of d-wave pairing collapses at T_c like the BCS-type superconductors, or it instead survives above T_c turning into the preformed pair state. A difficulty in this issue comes from the small magnitude of the nodal gap, which has been preventing experimentalists from solving it. Here we use a laser ARPES capable of ultrahigh-energy resolution, and detect the point nodes surviving far beyond T_c in Bi2212. By tracking the temperature evolution of spectra, we reveal that the superconductivity occurs when the pair-breaking rate is suppressed smaller than the single-particle scattering rate on cooling, which governs the value of T_c in cuprates.

The pairing gap of the high-T_c cuprates has been expected to close at the transition temperature, similarly to the case of conventional superconductors. Here the authors perform ARPES measurements on Bi2212, and reveal a point nodal gap formation beyond T_c, characterized in terms of three parameters.

Critical factors that influence the early outcome of laparoscopic total gastrectomy

BACKGROUND

Laparoscopic distal gastrectomy (LDG) is a routinely performed procedure. However, clinical expertise in laparoscopic total gastrectomy (LTG) is insufficient, and it is only performed at specialized institutions. This study aimed to identify critical factors associated with complications after laparoscopic gastrectomy (LG), particularly LTG.

METHODS

A large-scale database was used to identify critical factors influencing the early outcomes of LTG. Of 1248 patients with resectable gastric cancer who underwent LG, 259 underwent LTG. Predictive risk factors were determined by analyzing relationships between clinical characteristics and postoperative complications. Major complications after LTG were analyzed in detail.

RESULTS

Multivariate analysis of all LG procedures revealed LTG as a risk factor for complications. Morbidity in the LDG and LTG groups was 6.2 % (52 of 835 patients) and 22.4 % (58 of 259 patients), respectively. Major post-LTG complications included anastomotic leakages and pancreatic fistulae. The rate of anastomotic leakage was significantly higher in the LTG group (5.0 %) than in the LDG group (1.2 %); however, it showed a tendency to decrease in more recent cases. Pancreatic fistulae occurred frequently after LTG with D2 lymphadenectomy (LTG-D2), particularly in cases of concomitant pancreatosplenectomy. Obesity was also associated with pancreatic fistula formation after LTG with pancreatosplenectomy.

CONCLUSIONS

Compared with LDG, LTG is a developing procedure. Advances in the surgical techniques associated with the LTG procedure will improve the short-term outcomes of esophagojejunostomy. With regard to LTG-D2, establishing optimal and safe #10 node dissection is one of the most urgent issues. Pancreatic fistula after LTG with pancreatosplenectomy must be investigated in the future.