柴崎 晋

BACKGROUND: Postoperative pancreatic fistula (POPF) is one of the potentially serious complications after gastrectomy for gastric cancer (GC). Drain amylase level is a predictor of POPF in open and laparoscopic gastrectomy, but no study has focused on minimally invasive surgery (MIS), including robotic gastrectomy (RG). This study assesses the effect of drain amylase levels for POPF in MIS and develop a prediction model in the MIS era. METHODS: This single-institutional retrospective study, conducted from January 2011 to December 2021, included 1,353 who underwent standard MIS for GC. We placed a drain in all patients undergoing MIS gastrectomy and measured the drain amylase level on the first postoperative day (D1Amy). The predictive accuracy of D1Amy for POPF was assessed. Additionally, the entire cohort was randomly categorized into the training (1,048 patients) and validation sets (305 patients) to establish the nomogram. RESULTS: Of the 1353 patients, 530 underwent a robotic approach. POPF and intraabdominal infectious complications of Clavien-Dindo classification grade ≥ II were observed in 80 (5.9%) and 145 (10.7%) patients, respectively. Median D1Amy was 812 U/L. The receiver operating characteristic analysis of D1Amy for POPF revealed an area under the curve (AUC) of 0.888. Multivariate analysis revealed age, tumor location, splenectomy, and D1Amy as significant risk factors for POPF. The AUC of the nomogram was 0.8960, validated with AUC of 0.9259. CONCLUSIONS: We revealed the utility of D1Amy in predicting POPF in MIS gastrectomy. Furthermore, the nomogram, incorporating D1Amy and other clinical factors, was additionally used as a predictive model for POPF.

BACKGROUND: Advanced gastric cancer with gastric outlet obstruction (GOO) causes malnutrition and medication adherence issues, leading to a poor prognosis. We developed a novel multimodal, less invasive treatment approach for gastric cancer patients with symptomatic GOO: laparoscopic stomach-partitioning gastrojejunostomy (LSPGJ) combined with neoadjuvant chemotherapy (NAC), followed by minimally invasive gastrectomy with reuse of gastrojejunostomy. This study is a retrospective analysis of the safety and feasibility of our treatment strategy. METHODS: In this single-institution retrospective study, we enrolled 54 patients (NAC group, n = 26; upfront gastrectomy group, n = 28) who achieved R0 resection through a minimally invasive approach between 2007 and 2020 and evaluated their short- and long-term outcomes. RESULTS: After LSPGJ, the Gastric Outlet Obstruction Scoring System score significantly improved (p < 0.001). The median relative dose intensity of NAC was 88.2%. Regarding short-term outcomes, there were no differences in postoperative complications, length of postsurgical hospital stay, and adjuvant chemotherapy administration. Although overall survival and relapse-free survival showed trends toward improvement in the NAC group, these differences were not statistically significant. The cumulative incidence curve for recurrence in the NAC group was significantly lower than that of the upfront gastrectomy group (p = 0.041). Recurrence and hematogenous metastasis were significantly lower in the NAC group (p = 0.031 and 0.041, respectively) than in the upfront gastrectomy group. A forest plot revealed that NAC yielded favorable outcomes, particularly for patients with a body mass index (BMI) < 18.5 kg/m2, cT4, or cN1. CONCLUSIONS: LSPGJ combined with NAC followed by minimally invasive gastrectomy was a safe and feasible treatment strategy for patients with advanced gastric cancer with symptomatic GOO. This procedure may contribute to the early recovery of oral intake and help maintain NAC dose intensity, potentially improving prognosis, particularly for patients with low BMI and advanced-stage disease.

BACKGROUND: Telesurgery has been made increasingly possible with the advancements in robotic surgical platforms and network connectivity. However, long-distance transnational complex robotic surgeries such as gastrectomy have yet to be attempted. METHODS: Multiple transnational network connections by Science Innovation Network (SINET), Japan Gigabit Network (JGN), and Arterial Research and Education Network in Asia-Pacific (ARENA-PAC) were established and tested by multiple surgeons in a dry box model. Surgeons' perceptions of the different networks were recorded. Three robotic radical D2 gastrectomies in live porcine models were performed at a hospital in Toyoake, Japan, by a surgical team in a hospital in Singapore ~5000 km away, using the hinotori Surgical Robot System (Medicaroid Corporation). RESULTS: The live porcine robotic gastrectomies were all completed in under 205 min with no intraoperative complications. From the different networks that were tested, the differences in latency ranged from 107 to 132 ms and did not translate to any significant differences in surgeon timings and perceptions. CONCLUSIONS: Transnational telesurgical radical D2 gastrectomy is feasible in a porcine model. There is no appreciable difference between surgeon performance and perception with network latencies of 107-132 ms. Long-range telesurgery as clinical practice may become possible in the future.

BACKGROUND: Posthepatectomy liver failure (PHLF) remains a severe complication after liver resection. This retrospective study investigated the correlation of three hepatic functional tests and whether 99mTc-galactosyl human serum albumin (99mTc-GSA) scintigraphy and modified albumin-bilirubin (ALBI) score are useful for predicting PHLF. METHODS: This retrospective cohort study included 413 consecutive patients undergoing hepatectomies between January 2017 and December 2020. To evaluate preoperative hepatic functional reserve, modified ALBI grade, indocyanine green clearance (ICG-R15), and 99mTc-GSA scintigraphy (LHL15) were examined before scheduled hepatectomy. Based on a retrospective chart review, multivariable logistic regression analysis adjusted for confounding factors was performed to confirm that mALBI, ICG-R15, and LHL15 are independent risk factors for PHLF. RESULTS: ICG-R15 and LHL15 were moderately correlated (r =  - 0.61) but this correlation weakened when ICG-R15 was about ≥ 20. Weak correlations were observed between LHL15 and ALBI score (r =  - 0.269) and ALBI score and ICG-R15 (r = 0.339). Of 413 patients, 66 (19%) developed PHLF (20 grade A, 44 grade B, 2 grade C). Multivariable logistic regression analyses, major hepatectomy (P < 0.001), mALBI grade (P = 0.01), ICG-R15 (P < 0.001), and Esophagogastric varices (P = 0.007) were significant independent risk factors for PHLF. Subgroup analysis showed that ICG-R15 < 19, major hepatectomy, and mALBI grade and ICG-R15 ≥ 19, major hepatectomy, LHL15, and Esophagogastric varices were significant independent risk factors for PHLF (P = 0.033, 0.017, 0.02, 0.02, and 0.001, respectively). CONCLUSION: LHL15, the assessment of Esophagogastric varices, and mALBI grade are complementary to ICG-R15 for predicting PHLF risk.

BACKGROUND: Nonresectable gastric cancer develops rapidly; thus, monitoring disease progression especially in patients receiving nivolumab as late-line therapy is important. Biomarkers may facilitate the evaluation of nivolumab treatment response. Herein, we assessed the utility of serum-based inflammatory indicators for evaluating tumor response to nivolumab. METHODS: This multicenter retrospective cohort study included 111 patients treated with nivolumab monotherapy for nonresectable advanced or recurrent gastric cancer from October 2017 to October 2021. We measured changes in the C-reactive protein (CRP)-to-albumin ratio (CAR), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) in serum from baseline to after the fourth administration of nivolumab. Furthermore, we calculated the area under the receiver operating characteristic curves (AUC ROCs) for CAR, PLR, and NLR to identify the optimal cutoff values for treatment response. We also investigated the relationship between clinicopathologic factors and disease control (complete response, partial response, and stable disease) using the chi-squared test. RESULTS: The overall response rate (complete and partial response) was 11.7%, and the disease control rate was 44.1%. The median overall survival (OS) was 14.0 (95% CI 10.7‒19.2) months, and the median progression-free survival (PFS) was 4.1 (95% CI 3.0‒5.9) months. The AUC ROCs for CAR, PLR, and NLR before nivolumab monotherapy for patients with progressive disease (PD) were 0.574 (95% CI, 0.461‒0.687), 0.528 (95% CI, 0.418‒0.637), and 0.511 (95% CI, 0.401‒0.620), respectively. The values for changes in CAR, PLR, and NLR were 0.766 (95% CI, 0.666‒0.865), 0.707 (95% CI, 0.607‒0.807), and 0.660 (95% CI 0.556‒0.765), respectively. The cutoff values for the treatment response were 3.0, 1.3, and 1.4 for CAR, PLR, and NLR, respectively. The PFS and OS were significantly longer when the treatment response values for changes in CAR, PLR, and NLR were below these cutoff values (CAR: OS, p < 0.0001 and PFS, p < 0.0001; PLR: OS, p = 0.0289 and PFS, p = 0.0302; and NLR: OS, p = 0.0077 and PFS, p = 0.0044). CONCLUSIONS: Measurement of the changes in CAR, PLR, and NLR could provide a simple, prompt, noninvasive method to evaluate response to nivolumab monotherapy. TRIAL REGISTRATION: This study is registered with number K2023006.

Abstract Background The advantages of robot‐assisted minimally invasive esophagectomy (RA‐MIE) over conventional minimally invasive esophagectomy (C‐MIE) are unknown. This nationwide large‐scale study aimed to compare surgical outcomes between RA‐MIE and C‐MIE using rigorous propensity score methods, including detailed covariates and relevant outcomes. Methods This Japanese nationwide retrospective cohort study included RA‐MIE or C‐MIE for esophageal malignant tumors performed between October 2018 and December 2019 and registered in the Japanese National Clinical Database. The primary outcome measure was postoperative complications classified as Clavien–Dindo Grade IIIa or higher. Propensity score matching was performed to create a balanced covariate distribution between the two groups. Results After propensity score matching, 1092 patients were selected. The RA‐MIE group had a significantly longer operation time and greater blood loss than the C‐MIE group (565 vs. 477 min and 120 vs. 90 mL). Furthermore, the R0 resection rate was lower in the RA‐MIE group than in the C‐MIE group (95.1% vs. 97.8%). The RA‐MIE and C‐MIE groups had no differences regarding overall complications ≥ Grade IIIa (22.0% vs. 20.3%, p = 0.52), 30‐day mortality rates (0.4% vs. 0.5%), and operative mortality rates (0.7% vs. 0.7%). Deep SSI was less frequent (2.7% vs. 6.0%) and pulmonary embolism was more frequent (2.4% vs. 0.5%) in the RA‐MIE group than in the C‐MIE group. Conclusions In the initial phase of implementation, RA‐MIE and C‐MIE demonstrated comparable morbidity rates when performed by skilled board‐certified endoscopic surgeons.

Concurrent direct and indirect inguinal, femoral, and obturator hernias are rare. This case report describes a rare case treated using the laparoscopic approach. A 68-year-old female patient presented with a moving left inguinal lump and pain. Physical examination and abdominal computed tomography scan revealed the coexistence of a left inguinal hernia or Nuck canal hydrocele and a left femoral hernia. The patient underwent laparoscopic transabdominal preperitoneal repair, and all four orifices were covered with one mesh. The patient was discharged on the second postoperative day without any complications. The concurrent presence of four hernias on the same side is rare and has not been previously reported. The laparoscopic approach is useful in such cases because it allows visualization of multiple hernia orifices from the intra-abdominal cavity.

BACKGROUND: Although the da Vinci™ Surgical System is the most predominantly used surgical robot worldwide, other surgical robots are being developed. The Japanese surgical robot hinotori™ Surgical Robot System was launched and approved for clinical use in Japan in November 2022. We performed the first robotic gastrectomy for gastric cancer using hinotori in the world. Here, we report our initial experience and evaluation of the feasibility and safety of robotic gastrectomy for gastric cancer using hinotori. METHODS: A single-institution retrospective study was conducted. Between November 2022 and October 2023, 24 patients with gastric cancer underwent robotic gastrectomy with hinotori. Five ports, including one for an assistant, were placed in the upper abdomen, and gastric resection with standard lymphadenectomy and intracorporeal reconstruction were performed. The primary endpoint was the postoperative complication rate within 30 days after surgery. The secondary outcomes were surgical outcomes, including intraoperative adverse events, operative time, blood loss, and the number of dissected nodes. RESULTS: Of the 24 patients, 16 (66.7%) were male. The median age and body mass index were 73.5 years and 22.9 kg/m2, respectively. Twenty-three patients (95.8%) had tumors in the middle to lower stomach. Sixteen (66.7%) and seven (29.2%) patients had clinical stage I and II diseases, respectively. Twenty-three (95.8%) patients underwent distal gastrectomy. No patient had postoperative complications of Clavien-Dindo classification IIIa or higher, whereas two (8.3%) had the grade II complications (enteritis and pneumonia). No intraoperative adverse events, including conversion to other approaches, were observed. All patients received R0 resection. The median operative and console times were 400 and 305 min, respectively. The median blood loss was 14.5 mL, and the number of lymph nodes dissected was 51.5. CONCLUSIONS: This study found that robotic gastrectomy with standard lymphadenectomy for gastric cancer using hinotori can be safely performed.

BACKGROUND: This study aimed to determine the safety and feasibility of minimally invasive gastrectomy in patients who underwent preoperative chemotherapy for highly advanced gastric cancer. METHODS: Preoperative chemotherapy was indicated for patients with advanced large tumors (≥ cT3 and ≥ 5 cm) and/or bulky node metastasis (≥ 3 cm × 1 or ≥ 1.5 cm × 2). Between January 2009 and March 2022, 150 patients underwent preoperative chemotherapy followed by gastrectomy with R0 resection, including conversion surgery (robotic, 62; laparoscopic, 88). The outcomes of these patients were retrospectively examined. RESULTS: Among them, 41 and 47 patients had stage IV disease and underwent splenectomy, respectively. Regarding operative outcomes, operative time was 475 min, blood loss was 72 g, morbidity (grade ≥ 3a) rate was 12%, local complication rate was 10.7%, and postoperative hospital stay was 14 days (Interquartile range: 11-18 days). Fifty patients (33.3%) achieved grade ≥ 2 histological responses. Regarding resection types, total/proximal gastrectomy plus splenectomy (29.8%) was associated with significantly higher morbidity than other types (distal gastrectomy, 3.2%; total/proximal gastrectomy, 4.9%; P < 0.001). Specifically, among splenectomy cases, the rate of postoperative complications associated with the laparoscopic approach was significantly higher than that associated with the robotic approach (40.0% vs. 0%, P = 0.009). In the multivariate analysis, splenectomy was an independent risk factor for postoperative complications [odds ratio, 8.574; 95% confidence interval (CI), 2.584-28.443; P < 0.001]. CONCLUSIONS: Minimally invasive gastrectomy following preoperative chemotherapy was feasible and safe for patients with highly advanced gastric cancer. Robotic gastrectomy may improve surgical safety, particularly in the case of total/proximal gastrectomy combined with splenectomy.

BACKGROUND: Hydrocele of the canal of Nuck (HCN) is a rare disease, and its indications for laparoscopic surgery are not well-established. CASE PRESENTATION: A 53-year-old woman was referred to our hospital due to an uncomfortable thumb-sized inguinal mass. Preoperative computed tomography scan and magnetic resonance imaging revealed a hydrocele extending from the abdominal cavity around the left deep inguinal ring via the inguinal canal to the subcutaneous space. The patient was diagnosed with HCN protruding into the abdominal cavity and extending to the subcutaneous space. Laparoscopy can easily access the hydrocele protruding into the abdominal cavity. Furthermore, laparoscopic hernioplasty can be superior to the anterior approach for females. Hence, laparoscopic surgery was performed. After transecting the round ligament of the uterus, a tense 3-cm hydrocele was dissected with it. In order to approach the hydrocele distal to the deep inguinal ring, the transversalis fascia was incised medially to the inferior epigastric vessels. The subcutaneously connected hydrocele was excised from the incision. Then, the enlarged deep inguinal ring was reinforced using a mesh with the laparoscopic transabdominal preperitoneal approach. The patient was discharged 2 days postoperatively. Laparoscopic resection can be more effective for a hydrocele protruding into the abdominal cavity as it facilitates an easy access to the hydrocele. Moreover, laparoscopic resection of a hydrocele extending from the inguinal canal to the subcutaneous space via a transversalis fascia incision can be safer, with low risk of injury to the inferior epigastric vessels. The incised transversalis fascia and the enlarged deep inguinal ring due to the HCN were simultaneously repaired with the laparoscopic transabdominal preperitoneal repair. There are two reports on laparoscopic resection via a transversalis fascia incision for HCNs located between the inguinal canal and the subcutaneous space, which does not require intraperitoneal hydrocelectomy. However, this is the first report on laparoscopic resection of large HCNs protruding into the abdominal cavity and extending beyond the inguinal canal into the subcutaneous space via intraperitoneal hydrocelectomy and a transversalis fascia incision. CONCLUSIONS: Laparoscopic surgery with transversalis fascia incision can be useful for HCNs extending from the abdominal cavity to the subcutaneous space.

BACKGROUND: Laparoscopic gastrectomy (LG) for remnant gastric cancer (RGC) remains controversial because of its rarity and heterogeneity of clinical characteristics. Based on our experience, we posited that our established methodology in LG could be applied to the laparoscopic procedure for RGC surgery and introduced LG for RGC at our institution in 2004. METHODS: This study enrolled 46 patients who underwent LG for RGC between January 2004 and December 2017. Data were obtained through a review of our prospectively maintained database. Laparoscopic total gastrectomy (LTG) was the standard surgical procedure for RGC. Laparoscopic subtotal gastrectomy (LsTG) was performed as an alternative procedure for patients with RGC located near the anastomotic site after primary gastrectomy. The technical and oncological feasibility and safety of LG for RGC were evaluated. RESULTS: LTG for RGC was performed on 36 patients. LsTG for RGC was performed on 10 patients. All patients completed LG procedure and succeeded R0 resection. Complications of Clavien-Dindo classification grade ≥ IIIa occurred in 4 (8.7%) patients. The retrospective video reviews showed that the time for adhesiotomy around the suprapancreatic area and the lesser curvature of the remnant stomach was significantly shorter in the primary-benign group than in the primary-malignant group. With the median follow-up period of 40 months, the 3-year recurrence-free survival and 3-year overall survival rates were 72.3% and 80.2%, respectively. CONCLUSION: LG for RGC represents a safe and feasible surgical option with favorable short-term and long-term outcomes in patients with RGC.

BACKGROUND: Systematic lymph node dissection in patients with gastric cancer could be sufficiently and reproducibly achieved along the outermost layer of the autonomic nerves and similar concept has been extensively used for robotic esophagectomy (RE) since 2018. This study aimed to determine the surgical and oncological safety of RE using the outermost layer-oriented approach for esophageal cancer (EC). METHODS: Sixty-six patients who underwent RE with total mediastinal lymphadenectomy for primary EC between April 2018 and December 2021 were retrospectively reviewed. All underwent the outermost layer-oriented approach with intraoperative nerve monitoring (IONM). Postoperative complications within 30 days were analyzed. RESULTS: Among the patients, 51 (77.3%) were male. The median age was 64 years, and the body mass index was 21.8 kg/m2. Furthermore, 58 (87.9%) patients had squamous cell carcinoma and eight (12.1%) patients had adenocarcinoma. Clinical stages I, II, and III were seen in 23 (34.8%), 23 (34.8%), and 16 (24.2%) patients, respectively. Thirty-four (51.5%) patients received preoperative treatment. No patient shifted to conventional thoracoscopic or open procedure intraoperatively. The median operative time was 716 min with 119 mL of blood loss. Additionally, 64 (97%) patients underwent R0 resection. The morbidity rates based on Clavien-Dindo grades ≥ II and ≥ IIIa were 30.3% and 10.6%, respectively, within 30 postoperative days. None died within 90 days postoperatively. Three (4.5%) patients exhibited recurrent laryngeal nerve (RLN) palsy (CD grade ≥ II). The sensitivity and specificity of IONM for RLN palsy were 50% and 98.3% at the right RLN and 33.3% and 98.0% at the left RLN, respectively. CONCLUSION: RE with the outermost layer-oriented approach can provide safe short-term outcomes.

PURPOSE: As a safe and reliable alternative to central venous catheters (CVCs), peripherally inserted central catheters (PICCs) are commonly used in clinical practice. However, the insertion of PICCs by nurse practitioners (NPs), especially in Japan, has not been reported extensively. Thus, we investigated the safety and efficiency of PICC insertions by NPs. METHODS: The participants were 1322 patients who underwent PICC insertion by NPs at Fujita Health University Hospital (FNPs). The basilic vein in the brachium was the preferred vein for insertion; the brachial vein was the alternative. Patients were monitored from the time of PICC insertion until its removal. Ultrasonography-guided puncture was used for all catheter insertions, and the catheter tip was replaced into the superior vena cava under fluoroscopic imaging with maximal sterile barrier precautions. The outcomes of the PICC insertions by the FNPs were evaluated retrospectively. RESULTS: Overall, 23 FNPs inserted a collective total of 1322 PICCs, which remained in place for a collective total of 23,619 catheter days. The rate of successful PICC insertion was 99% (1310 patients). The median time taken for PICC insertion was 12 min (interquartile range, 10-15 min). Intraoperative complications occurred in two patients (0.2%). The confirmed incidence of central line-associated bloodstream infection was 3.4% (45 patients), and these infections occurred on 1.9 per 1000 catheter days. The median duration of PICC placement was 15 days (range, 10-23 days). CONCLUSION: PICC insertion by NPs is safe and a potential alternative to CVC insertion by surgeons.

PURPOSE: Postoperative diarrhea (PD) remains one of the significant complications. Only a few studies focused on PD after minimally invasive surgery. We aimed to investigate PD after minimally invasive gastrectomy for gastric cancer. METHODS: A total of 1476 consecutive patients with gastric cancer undergoing laparoscopic or robotic gastrectomy between 2009 and 2019 at our institution were retrospectively reviewed. PD was defined as continuous diarrhea for ≥ 2 days, positive stool culture, or positive clostridial antigen test. The incidence, causes, and related clinical factors were analyzed. RESULTS: Of the 1476 patients, the median age was 69 years. Laparoscopic and robotic approaches were performed in 1072 (72.6%) and 404 (27.4%), respectively. Postoperative complications with Clavien-Dindo classification grade of ≥ IIIa occurred in 108 (7.4%) patients. PD occurred in 89 (6.0%) patients. Of the 89 patients with PD, Clostridium difficile, enteropathogenic Escherichia coli, and methicillin-resistant Staphylococcus aureus were detected in 24 (27.0%), 16 (33.3%), and 7 (14.6%) patients, respectively. Multivariate analysis revealed that age ≥ 75 years (OR 1.62, 95% CI [1.02-2.60], p = 0.042) and postoperative complications (OR 6.04, 95% CI [3.54-10.32], p < 0.001) were independent risk factors for PD. In patients without complications, TG (OR 1.88) and age of ≥ 75 years(OR 1.71) were determined as independent risk factors. CONCLUSION: The incidence of PD following minimally invasive gastrectomy for gastric cancer was 6.0%. Older age and TG were obvious risk factors in such a surgery, with the latter being a significant risk even in the absence of complications.

BACKGROUND: Valvuloplastic esophagogastrostomy (VEG) using the double flap technique (DFT) after proximal gastrectomy (PG) represents a promising procedure for the prevention of reflux oesophagitis. We aimed to retrospectively investigate the efficacy of minimally invasive PG followed by VEG-DFT in preventing reflux oesophagitis among patients who require intra-mediastinal anastomosis. METHODS: A total of 80 patients who underwent reconstruction with DFT after LPG from November 2013 to January 2021 were enrolled in the present study. Data were obtained through a review of our prospectively maintained database. At 1 year after surgery, multivariate analyses were performed to identify risk factors for gastroesophageal reflux disease of Los Angeles (LA) classification grade B or higher. RESULTS: The incidence of LA grade B or higher reflux oesophagitis 1 year after surgery was 10%. Multivariate analyses revealed that the longitudinal length of the resected oesophagus of > 20 mm was the only significant risk factor for reflux oesophagitis. Patients with a longitudinal length of the resected oesophagus > 20 mm (group-L, n = 35) had a significantly longer total operative time and a higher rate of complications within 30 days of surgery than those with a length of ≤ 20 mm (group-S, n = 45). LA grade B or higher reflux oesophagitis was significantly higher in group-L than in group-S (20% vs. 2.2%; P = 0.011). CONCLUSIONS: There is a need for surgical procedures with improved efficacy for the prevention of reflux oesophagitis in patients requiring oesophageal resection of > 20-mm.

BACKGROUND: Robotic gastrectomy (RG) using the da Vinci Surgical System for gastric cancer was approved for national medical insurance coverage in Japan in April 2018, and its number has been rapidly increasing since then. AIM: We reviewed and compared current evidence on RG and conventional laparoscopic gastrectomy (LG) to identify the differences in surgical outcomes. METHODS: Three independent reviewers systematically reviewed the data collected from a comprehensive literature search by an independent organization, focusing on the following nine endpoints: mortality, morbidity, operative time, estimated blood loss volume, length of postoperative hospital stay, long-term oncologic outcome, quality of life, learning curve, and cost. RESULTS: Compared to LG, RG has lower intraoperative blood loss volume, shorter length of hospital stay, and shorter learning curve, but both procedures have similar mortality. Contrarily, its disadvantages include longer procedural time and higher costs. Although the morbidity rate and long-term outcomes are almost comparable, RG showed superior potentials. Currently, the outcomes of RG are considered comparable to or better than LG. CONCLUSION: RG might be applicable to all gastric cancer patients who fulfill the indication of LG at institutions that meet specific criteria and are approved to claim the National Health Insurance costs for the use of the surgical robot in Japan.

PURPOSE: Robotic gastrectomy (RG) for gastric cancer (GC) was approved for national medical insurance coverage in April, 2018, since when its use has increased dramatically throughout Japan. However, the safety of RG performed by surgeons who are not Endoscopic Surgical Skill Qualification System (ESSQS)-qualified has yet to be established. We conducted this study to verify the short-term outcomes of the initial series of RG procedures performed by non-ESSQS-qualified surgeons. METHODS: Between January, 2020 and December, 2021, 30 patients with clinical Stage I and II GC underwent RG performed by four non-ESSQS-qualified surgeons according to the Japan Society for Endoscopic Surgery guideline. We evaluated, retrospectively, the morbidity rates according to Clavien-Dindo (CD) classification grade II or higher. RESULTS: Each operating surgeon completed all procedures without any serious intraoperative adverse events. The median operative time, console time, and estimated blood loss were 413 (308-547) min, 361 (264-482) min, and 25.5 (4-167) mL, respectively. No patient required conversion to laparoscopic or open surgery. Three (10%) patients suffered CD grade II complications postoperatively. The median postoperative hospitalization was 11 (8-51) days. CONCLUSION: Non-ESSQS-qualified surgeons trained by expert RG surgeons could perform robotic distal gastrectomy safely for initial cases.

BACKGROUND: The current study aimed to investigate the relationship between muscle mass proportion and the incidence of total complications in male gastric cancer (GC) patients after minimally invasive distal gastrectomy (MIDG). METHODS: Between March 2017 and March 2020, 152 male GC patients with clinical stage III or lower GC who underwent MIDG were enrolled in this study. The muscle mass ratio (MMR) was calculated by dividing the total muscle weight obtained from bioelectrical impedance analysis by the whole-body weight. Thereafter, the association between MMR and surgical outcomes was determined. RESULTS: Based on the optimal MMR cutoff value of 0.712 obtained using the receiver operating characteristic (ROC) curve, patients were divided into two groups (69 and 83 patients in the MMR-L and MMR-H groups). The MMR-L group had a significantly higher total complication rate compared to the MMR-H group (MMR-L, 24.6% vs. MMR-H, 7.2%; P = 0.005). Multivariate analysis also identified MMR-L as a significant independent risk factor for total complications and intra-abdominal infectious complications after MIDG. CONCLUSIONS: The MMR calculated using bioelectrical impedance analysis can be a useful predictor for postoperative complications after MIDG in male GC patients.

BACKGROUND: Anastomotic leakage of cervical esophagogastrostomy following radical esophagectomy for esophageal cancer has reduced over time; however, postoperative anastomotic stricture still occurs at a considerably high rate. We developed a novel method of circular-stapled esophagogastrostomy by employing the keyhole procedure, which uses a linear stapler to enlarge the anastomotic opening made with a circular stapler (CS). METHODS: We retrospectively reviewed 70 patients with esophageal cancer who underwent transthoracic esophagectomy and reconstruction via cervical CS-mediated anastomosis with or without the keyhole procedure between 2018 and 2020. The primary outcome was postoperative anastomotic stricture incidence within 180 days after surgery. RESULTS: Among 70 patients, 22 underwent the keyhole procedure (CS + K group) and the remaining did not (CS group). No differences were observed in patients' age, sex, body mass index, performance status, American Society of Anesthesiologists physical status, Charlson's comorbidity index, tumor histological type, tumor location, clinical stage, or preoperative treatment. A smaller stapler was used in the CS + K group (p < 0.001). Incidence of anastomotic stricture was significantly different (CS vs. CS + K, 18.8 vs. 0%, p = 0.049), especially when a 21 or 23 mm CS was used (CS vs. CS + K, 50.0 vs. 0%, p = 0.005). Univariate analysis confirmed that CS ≤ 23 without keyhole was a significant risk factor (p = 0.001). CONCLUSIONS: The keyhole procedure could be a simple and useful alternative technique that reduces the risk of stricture formation in cervical esophagogastric anastomosis, especially when using the smaller-sized CS.

Objective The aim of this study was to determine the safety and clinical efficacy of docetaxel+cisplatin+5-fluorouracil (DCF) as neoadjuvant chemotherapy (NAC). Methods In this single-center study, patient background and treatment outcomes (NAC efficacy assessment, NAC adverse events, short-term postoperative outcomes, and one-year postoperative outcomes) in patients treated with preoperative DCF and preoperative cisplatin+5-FU (CF) were compared retrospectively. Patients Seventeen patients diagnosed with esophageal squamous cell carcinoma (ESCC) and treated with preoperative DCF therapy and 50 patients treated with preoperative CF therapy between January 2013 and July 2019 were included in this study. Results There were significant differences in clinical T factor and clinical stage between the CF and DCF groups (p<0.05). All patients in the DCF therapy group were above clinical T3 and clinical stage III. The clinical response after NAC was partial response (PR) for 23 patients (46.0%) in the CF group and 13 patients (76.5%) in the DCF group (p=0.030). Regarding adverse events in NAC, neutropenia, febrile neutropenia (FN), diarrhea, and stomatitis were observed more frequently in the DCF group than in the CF group (p<0.05). The postoperative results [overall survival (OS), recurrence-free survival (RFS), one-year OS, one-year RFS] of the DCF group were comparable to those of the CF group. Conclusion DCF therapy has been recognized as an effective treatment option for advanced ESCC. However, the indication for DCF therapy should be chosen carefully because of the high incidence of adverse events.

BACKGROUND: A giant inguinoscrotal hernia is a rare inguinal hernia that extends below the midpoint of the inner thigh while standing. Although reports of laparoscopic surgery for giant inguinoscrotal hernias have increased, the risk of delayed hematocele has not yet been clarified. CASE PRESENTATION: A 68-year-old man was evaluated for a left giant inguinoscrotal hernia, and laparoscopic transabdominal preperitoneal repair (TAPP) was performed. In the procedure, the distal hernia sac was not resected. The postoperative course was uneventful for 3 months postsurgery, after which he complained of giant scrotal swelling, which gradually grew to 13 cm. It did not improve with several punctures and caused dysuria because of increased pressure on the urethra. Thus, reoperation was performed 9 months after surgery. The hematocele consisted of a thickened hernia sac, which was tightly adhered to the spermatic cord and testicle. The hernia sac including the hematocele was removed from the scrotum through an anterior approach, preserving the spermatic cord and testicle. On the third postoperative day, an orchiectomy was performed due to poor testicular perfusion caused by spermatic cord injury. There was no hematocele or hernia at the 3-year follow-up. The remnant sac after laparoscopic TAPP for a giant inguinoscrotal hernia possibly caused refractory hematocele. Additionally, the removal of the hernia sac, including hematocele, from the spermatic cord and testicle has a risk of inducing injury, leading to orchiectomy. CONCLUSION: Surgeons should be aware of the possibility of delayed refractory hematoceles after laparoscopic TAPP for giant inguinoscrotal hernias when the hernia sac is not resected.

BACKGROUND: Oncological benefits of robotic gastrectomy (RG) remain unclear. We aimed to determine and compare the 3-year outcomes of RG and laparoscopic gastrectomy (LG) for the treatment of gastric cancer. METHODS: This was a multi-institutional retrospective study of patients who prospectively underwent RG in a previous study (UMIN000015388) and historical controls who underwent LG. Operable patients with cStage I/II primary gastric cancer were enrolled. The inverse probability of treatment weighting method based on propensity scores was used to balance patient demographic factors and surgeon volume between the RG and LG groups. The primary outcome measure was the 3-year overall survival rate (3yOS). RESULTS: Of the 1,127 patients in the previous study, 326 and 752 patients in the RG and LG groups, respectively, completed the study. The standardized difference of all confounding factors was reduced to 0.09 or less after weighting. In the weighted population, 3yOS was 96.3% and 89.6% in the RG and LG groups, respectively (hazard ratio [HR] 0.34 [0.15, 0.76]; p = 0.009), whereas there was no difference in 3-year recurrence-free survival rate (3yRFS) between the two groups (HR 0.58 [0.32, 1.05]; p = 0.073). Sub-analyses showed that RG improved 3yOS (HR 0.05 [0.01, 0.38]; p = 0.004) and 3yRFS (HR 0.05 [0.01, 0.34]; p = 0.003) in patients with pStage IA disease. Recurrence rates and patterns were similar between the RG and LG groups. RG did not improve the morbidity rate, however, it attenuated some of the adverse events, including anastomotic leakage and intra-abdominal abscess. RG improved estimated blood loss and duration of postoperative hospitalization. CONCLUSION: This study showed surgical and oncological safety of RG for cStage I/II gastric cancer considering the 3-year outcomes, compared with those of LG.

症例は46歳,男性。健診で胃角部後壁に20mm大の粘膜下腫瘍を指摘された。超音波内視鏡検査では,第4層由来で内部不均一な低エコー腫瘤を認め,生検では確定診断に至らなかった。造影CT検査では同腫瘍は造影効果増強を受け,リンパ節や遠隔臓器に転移を認めなかった。GIST疑いとして手術適応となったが,残胃狭窄を考慮し,ロボット支援下幽門側胃切除術の方針とした。術中所見で残胃の通過に問題なく,局所切除術を施行した。術後経過は良好で9日目に退院となった。病理組織学的検査所見では顆粒細胞腫と診断された。また,手術支援ロボットにより胃局所切除にも安全,柔軟に対応できたと考えられた。(著者抄録)

症例は79歳,男性。心窩部不快感,食欲低下を主訴に近医を受診し,上部消化管内視鏡で胃体下部大彎に1型進行胃癌を認めた。造影CTで胃下壁からトライツ靱帯に及ぶ造影増強を伴う7cm大の腫瘤を認めたが,他に遠隔転移を認めなかった。進行胃癌とリンパ節転移,腹膜播種または胃GISTの診断で審査腹腔鏡を施行した。腫瘤は横行結腸に約3cm接していたが腫瘍の可動性は良好であり,腹膜播種を認めず,切除可能と判断し手術方針となった。胃全摘および横行結腸部分切除を施行し,病理検査ではpT3N1で胃大彎の腫瘤は胃癌による#4saリンパ節転移であった。現在,術後12ヵ月が経過し,再発を認めず生存中である。本症例について多少の文献的考察を加えて考察する。(著者抄録)

症例は78歳,男性。胃上部癌に対して前医で腹腔鏡下胃全摘術を施行された(U,Gre,pT3N0,pStage IIB)。術後2年6ヵ月で脾門部に腫瘤を認め,脾門部リンパ節転移または播種の疑いでSOXを2コース施行したが,増大傾向を認めた。他に病変を認めないため手術の方針となった。ロボット支援下膵尾部脾臓切除術を施行した(手術時間384分,出血量22mL)。経過良好で術後12日目に退院となった。病理検査では胃癌膵転移の診断であった。退院後にSOXを計3コース施行したが,再手術後2ヵ月で傍大動脈リンパ節転移と肝転移を認めたためsecond-lineとしてramucirumab+weekly paclitaxelを計16コース施行し,再手術から11ヵ月後の時点で再発巣は縮小を維持している。ロボット支援手術は腹腔鏡手術や開腹手術と比較して合併症が少ないという報告もあり,胃癌術後の孤発性転移の症例でもスムーズな周術期化学療法との連携に適していると考えられた。(著者抄録)

AIM: The recent development of new surgical robots and network telecommunication technology has opened new avenues for robotic telesurgery. Although a few gastroenterological surgeries have been performed in the telesurgery setting, more technically demanding procedures including gastrectomy with D2 lymphadenectomy and intracorporeal anastomosis have never been reported. We examined the feasibility of telesurgical robotic gastrectomy using the hinotori™ Surgical Robot System in a preclinical setting. METHODS: First, the suturing time in the dry model was measured in the virtual telesurgery setting to determine the latency time threshold. Second, a surgeon cockpit and a patient unit were installed at Okazaki Medical Center and Fujita Health University, respectively (approximately 30 km apart), and connected using a 10-Gbps leased optic-fiber network. After evaluating the feasibility in the dry gastrectomy model, robotic distal gastrectomies with D2 lymphadenectomy and intracorporeal B-I anastomosis were performed in two porcine models. RESULTS: The virtual telesurgery study identified a latency time threshold of 125 ms. In the actual telesurgery setting, the latency time was 27 ms, including a 2-ms telecommunication network delay and a 25-ms local information process delay. After verifying the feasibility of the operative procedures using a gastrectomy model, two telesurgical gastrectomies were successfully completed without any unexpected events. No fluctuation was observed across the actual telesurgeries. CONCLUSION: Short-distance telesurgical robotic surgery for technically more demanding procedure may be safely conducted using the hinotori Surgical Robot System connected by high-speed optic-fiber communication.

A 46-year-old man was referred to further treatment for a 20 mm submucosal tumor at the gastric angle found during a medical check-up. Endoscopic ultrasonography and chest abdominal contrast-enhanced CT revealed the tumor was located at the 4th(proper muscular)layer of the posterior wall of the gastric antrum and slightly enhanced. No metastasis was found. Although a biopsy failed to reveal an accurate diagnosis, GIST was clinically suspected. A robotic distal gastrectomy was planned to manage the residual gastric stricture. The intraoperative findings indicated possible passage of the remnant stomach; therefore, local resection was performed. The patient's postoperative course was uneventful, and he was discharged on postoperative day 9. A histopathological examination confirmed the diagnosis of a PAS-positive, S100-positive granular cell tumor with no nuclear atypia. These findings suggest that use of the robotic approach could help determine the stomach resection extent.

A 79-year-old male presented with epigastric discomfort and appetite loss. A type 1 advanced gastric tumor was detected by upper gastrointestinal endoscopy. Contrast-enhanced CT revealed a 7 cm mass with contrast effect at the greater curvature of the lower body of the stomach. No distant metastases were found. Staging laparoscopy confirmed gastric cancer with single giant lymph node metastasis, which was resectable, although the metastatic node possibly invaded the transverse colon. We performed total gastrectomy and partial colectomy. Pathological examination revealed the tumor was pT3N1; the mass was #4sa lymph node metastasis of gastric cancer. The postoperative course was uneventful. No tumor recurrence has been found for 12 months postoperatively.

A 78-year-old male who had received laparoscopic total gastrectomy for upper gastric cancer 30 months ago(pT3N0, pStage ⅡB)was referred for further treatment for a 30-mm in size mass at the splenic hilum. The mass was suspected of lymph node metastasis was suspected. Two courses of SOX therapy failed to achieve the tumor response. Since there was no other metastasis, surgical treatment was indicated. Robot distal pancreatectomy with splenectomy was performed. There was no finding of peritoneal metastasis during the operation. The operative time was 384 min, the blood loss 22 mL, respectively. The postoperative course was uneventful, and he was discharged on the 12th postoperative day. The histopathological examination found that the resected mass was pancreatic metastasis of gastric cancer. Despite 3 courses of SOX therapy after the operation, the tumor recurred at the liver and paraaortic lymph nodes 2 months later. The second-line ramucirumab plus paclitaxel was started and has continued for 11 months with partial response. Although oncological benefit of surgical resection for isolated metastasis of gastric cancer, including pancreatic metastasis, was unclear, the robotic approach for such an atypical case was safe and feasible, leading to smooth initiation of postoperative systemic therapy.

BACKGROUND/AIM: Immune-related adverse events (irAEs) are associated with the efficacy of nivolumab. However, whether the tolerability of second-line chemotherapy is associated with the efficacy of nivolumab monotherapy (third-line chemotherapy) remains unclear. Our study aimed to investigate whether the results of second-line treatment were associated with the efficacy of nivolumab in patients with gastric cancer. PATIENTS AND METHODS: We enrolled Japanese patients aged ≥20 years with gastric cancer who were treated with nivolumab as a third-line chemotherapy at Fujita Health University Hospital from October 2017 to September 2021. Patients with the evaluations of complete response, partial response, and stable disease after third-line chemotherapy were included in the disease control (DC) group, while others were included in the progressive disease (PD) group. RESULTS: A total of 126 patients were enrolled. The population of patients aged over 65 years in the DC group was significantly higher than that in the PD group. The number of patients continuing second-line chemotherapy for >7 months was significantly higher in the DC than in the PD group. Age over 65 years [odds ratio (OR)=2.67], duration of second-line chemotherapy over 7 months (OR=3.10), and the occurrence of irAEs (OR=3.60) were detected as the factors associated with disease control after nivolumab chemotherapy. CONCLUSION: The effect and tolerability of second-line chemotherapy, and age over 65 years are the factors associated with DC after nivolumab chemotherapy. The control of tumour inflammatory status might be important for improving treatment outcomes.

BACKGROUND: A leiomyosarcoma of the gastrointestinal tract is extremely rare. We report a case of jejunal leiomyosarcoma with intestinal intussusception at the angle of Treitz that was successfully treated with laparoscopic resection followed by intracorporeal reconstruction using a delta-shaped anastomosis. CASE PRESENTATION: A 54-year-old man was referred to our hospital due to fatigue and loss of appetite. Blood tests showed anemia. Enteroscopy and subsequent enterography using meglumine sodium amidotrizoate showed easily hemorrhagic tumor (10 cm in diameter) in the jejunum just beyond the angle of Treitz. Contrast-enhanced computed tomography revealed jejunojejunal intussusception. Histopathological examination of a biopsy specimen revealed a leiomyosarcoma. Laparoscopic resection of the tumor without reduction of the intussusception was performed. The resected line of the proximal intestine was very close to the ligament of Treitz in the present case. Intracorporeal jejunojejunostomy was completed using a delta-shaped anastomosis, wherein anastomosis was performed between the posterior walls of the proximal and distal jejunums after minimal mobilization around the ligament of Treitz. The patient's postoperative course was uneventful, and he was discharged at 10 days postoperatively. No recurrence has been observed within 2 years after surgery. CONCLUSIONS: We present a case in which a totally laparoscopic surgery for leiomyosarcoma located at the angle of Treitz with jejunojejunal intussusception was performed successfully.

＜文献概要＞ポイント ◆保険適用の拡大に伴って,ロボット支援下手術件数は急激に増加している.◆手術支援ロボットでは,da Vinciが先行していたが,国産手術支援ロボットをはじめ,今後,群雄割拠時代の到来が予想される.◆フルスペック型の手術支援ロボットだけでなく,カスタマイズ型も含め,選択の幅が広がることが期待される.

アレルギー反応に起因した急性冠症候群(acute coronary syndrome;以下,ACSと略記)はKounis症候群と呼ばれる.今回,我々は胃癌術後に発生したKounis症候群の1例を経験したので報告する.症例は既往歴のない60歳の男性で,胃癌の診断でロボット支援下幽門側胃切除術を施行した.術中偶発症など特になく手術は終了した.術後約6時間後に,突然HR 30台の徐脈と収縮期血圧60台への低下とST上昇を認めた.ACSを疑い緊急冠動脈造影検査を行ったが,冠動脈の狭窄所見は認めなかった.その一方で,検査前に左膝部に孤立性の膨疹が認められ,検査後に皮疹は両上下肢に広がっていた.薬剤アレルギーとそれに伴うACSであるKounis症候群と診断し,ステロイドを全身投与した.血圧は上昇し,その後のACSの再燃は認められなかった.ACSのリスクが低いにもかかわらずACSが強く疑われる際には,薬剤性アレルギーの可能性を念頭に置き迅速な対応が重要である.(著者抄録)

術前化学療法施行後にロボット支援下手術を施行し良好な転帰が得られた単発性肝転移を伴うStage IV胃癌の1例を経験したので報告する。症例は70代、男性。肝S3に転移を伴う進行胃癌(cT4aN+M1、cStage IV)と診断し、S-1/CDDP(SP)療法を開始した。4コース施行後の評価CTで転移性肝腫瘍は不明瞭化し、原発巣、リンパ節転移巣も著明な縮小を認めていた。この時点で手術を勧めたが本人は希望せず、SP療法を継続した。計23コース施行後の評価では肝転移巣は不明瞭化したままであったが、原発巣はやや増大を認めた。再度手術を勧めたところ希望されたため、ロボット支援下幽門側胃切除ならびに肝S3部分切除術を施行した。長期間にわたる抗癌剤治療の影響で組織の瘢痕化や脆弱化がみられたが、手術支援ロボットの特性を活かしoutermost layerの同定と同層を維持した郭清を進めていくことで出血が少なく過不足のない郭清手技を施行できた。手術時間391分、出血量は11mLであった。術後合併症は特になく、術後11日目に退院となった。術後病理診断では切除肝には悪性所見は認められず、ypT2N1M0、ypStage IIAであった。術後12ヵ月現在、無再発経過中である。(著者抄録)

今回,我々はロボット支援下胃切除術後早期に発症した仮性動脈瘤の1例を経験したので報告する.症例は43歳の男性で,2型進行胃癌に対してロボット支援下幽門側胃切除術,D2郭清を施行した.膵上縁郭清にやや難渋したが,術中偶発症なく手術を完遂した.術後3日目に腹腔内感染症の鑑別目的に腹部造影CTを施行したところ,脾動脈起始部の頭側に約1cmの仮性動脈瘤が疑われた.緊急血管造影を行い,背側膵動脈の分枝に仮性動脈瘤が認められたため,コイル塞栓術を施行した.後方視的に手術ビデオを検討すると,脾動脈近位部で膵背側から腹側に向かって走行する細い小動脈を不十分な凝固で切離しており,これが仮性動脈瘤形成の一因と考えられた.その後の経過は良好で術後16日目に退院した.ロボット支援手術でメリーランドバイポーラ鉗子を使用する際は意図しない不十分な凝固で小動脈を切離してしまうことがないよう注意が必要と考えられた.(著者抄録)

We report a successful case of robot-assisted surgery for Stage Ⅳ gastric cancer with liver metastasis. A 70s man diagnosed with advanced gastric cancer with S3 solitary liver metastasis, and received a chemotherapy with S-1 and cisplatin. After 4 courses of chemotherapy, liver metastatic lesion was disappeared. Thus, robotic distal gastrectomy and partial liver resection were performed. Operating time was 391 minutes, and amount of intraoperative blood loss was 11 mL. The postoperative course was uneventful, and the patient was discharged 11 days after surgery. Histologic examination revealed no viable malignant cells in the resected liver, with a diagnosis of ypT2N1M0, ypStage ⅡA. The patient is alive with no recurrence 12 months after surgery, without adjuvant chemotherapy.

食道癌術後の乳び胸はまれな合併症であり、治療法は確立されていない。今回われわれは、ロボット支援下食道亜全摘術後に乳び胸を発症した症例を経験したため報告する。症例は50歳、女性。進行食道癌のため術前化学療法を施行後、ロボット支援下食道亜全摘術を行った。術後経過は良好であったが、術後15日目に突然の呼吸苦が出現、CT検査で右胸水を認めた。右胸腔穿刺を施行し、乳び胸と診断した。完全中心静脈栄養管理・ソマトスタチンの投与を行ったが改善なく、術後20日目に右鼠径部よりリピオドールによるリンパ管造影検査を施行した。明らかな造影剤の漏出は認めなかったが、胸水は徐々に減少し術後28日目に胸腔ドレーンを抜去した。リピオドールによるリンパ管造影は、術後乳び胸に対する診断のみならず治療的観点からも有用な手技の一つと考えられた。(著者抄録)

A 50-year-old woman diagnosed with clinical Stage Ⅲ esophageal squamous cell carcinoma, received 2 cycles of docetaxel, cisplatin, 5-fluorouracil(DCF)therapy followed by robotic esophagectomy. In the 15th postoperative day, she suddenly had difficulty in breathing and a chest CT finding showed a large amount of right pleural effusion. Thoracocentesis yield a 1 L of chylous fluid confirmed diagnosis with postoperative chylothorax and conservative treatment was initiated. However, chylothorax was not improved. Therefore, a lipiodol lymphangiography from the inguinal lymph node was performed at the 20th postoperative day. Although the site of leakage could not identify, amount of drained pleural effusion was gradually decreased after lymphangiography, and drain was decannulated in the 28th postoperative day. Lipiodol lymphangiography may be a useful modality for both diagnosis and treatment for chylothorax after esophagectomy.