An advanced bipolar device helps reduce the rate of postoperative pancreatic fistula in laparoscopic gastrectomy for gastric cancer patients: a propensity score-matched analysis.

BACKGROUND: Advanced bipolar devices (ABD; e.g., LigaSure™) have a lower blade temperature than ultrasonically activated devices (USAD; e.g., Harmonic® and Sonicision™) during activation, potentially enabling accurate lymph node dissection with less risk of postoperative pancreatic fistula (POPF) due to pancreatic thermal injury in laparoscopic gastrectomy. Therefore, we compared the efficacy and safety of ABD and USAD in laparoscopic gastrectomy for gastric cancer patients. METHODS: A retrospective cohort study was conducted on patients who underwent laparoscopic distal gastrectomy (LDG) between August 2008 and September 2020. A total of 371 patients were enrolled, and short-term surgical outcomes, including the incidence of ISGPF grades B and C POPF, were compared between ABD and USAD. The risk factors for POPF in LDG were investigated by univariate and multivariate analyses. RESULTS: A propensity score-matching algorithm was used to select 120 patients for each group. The POPF rate was significantly lower (0.8 vs. 9.2%, p < 0.001), the morbidity rate was lower (13.3 vs. 28.3%, p < 0.001), the length of postoperative hospitalization was shorter (14 vs. 19 days, p < 0.001), and the lymph node retrieval rate was higher (34 vs. 26, p < 0.001) with an ABD than with a USAD. There were no mortalities in either group. A multivariate analysis showed that a USAD was the only independent risk factor with a considerably high odds ratio for the occurrence of POPF (USAD/ABD, odds ratio 8.38, p = 0.0466). CONCLUSION: An ABD may improve the safety of laparoscopic gastrectomy for gastric cancer patients.

Repeated partial tissue bite with inadequate cooling time for an energy device may cause thermal injury.

BACKGROUND: Over the past three decades, the use of ultrasonically activated device (USAD) and advanced bipolar device (ABD) has grown in minimally invasive surgeries. However, the thermal profile differences during repeated dissection with different grasping ranges of energy devices, which provide valuable information for preventing thermal injury by energy devices, remain unclear. METHODS: We developed an ex vivo benchtop model to examine the temperature profile of the blade and jaws of two USADs (HARMONIC® ACE + and Sonicision™) and a ABD (Ligasure™ Maryland) with different grasping ranges (partial tissue and full tissue bite) in repeated dissection with minimum cooling time. The maximum temperature, time required for completion to dissection of 10 cm of porcine muscle, thermal spread, and cooling time to reach 60 °C were continuously measured using video thermography. In addition, to evaluate one more grasping range "no tissue", we performed a stress test that activated the USAD without tissue intervention to assess the effects of excessive load on the blade and jaw. RESULTS: Repeated dissection of energy devices with minimal cooling time results in high blade and jaw temperatures proportional to the incision distance. In particular, the USADs with partial tissue bite showed a significantly higher temperatures at the blade and jaw, longer cooling times, and higher lateral thermal spread than those with a full tissue bite and the ABD. The stress test with a USAD showed an extremely high blade temperature exceeding 400 °C, with the tissue pad melting only 13.2 s after activation. CONCLUSION: Although USAD with partial tissue bite help ensure precise dissection, repeated long activation with inadequate cooling time may increase the risk of thermal injury during surgery. These results suggest that surgeons should use energy devices properly while understanding the risks of adjacent organ damage that could result from abuse of the device.

iTriangular Stapling Technique: A Novel Reconstruction Method and Clinical Outcomes of Cervical Esophagogastric Anastomosis after Esophagectomy.

BACKGROUND: We herein report the feasibility and safety of cervical end-to-end anastomosis by the iTriangular stapling technique (iTST), which was developed as an extension of the triangular stapling technique (TST) after minimally invasive esophagectomy (MIE). METHODS: A total of 45 patients with thoracic esophageal cancer who underwent reconstruction with cervical esophagogastric anastomosis by iTST using a linear stapler after MIE between January 2016 and January 2019 were retrospectively reviewed. We modified and improved upon the TST by adding a 1- to 2-cm vertical incision on the anterior wall of the remnant esophageal stump to enlarge the anastomotic lumen and thereby reduce the risk of anastomotic stenosis. The short-term patient outcomes were determined to assess the safety and feasibility of our procedures. RESULTS: The median operating time was 686 (range, 319-1110) minutes, and the median blood loss was 170 (range, 5-1180) ml. There were no cases of anastomotic stenosis in this study, although 2 patients (4.4%) developed minor anastomotic leakage. A case (2.2%) of tracheal fistula due to the apex of the triangular anastomosis was resolved simply by delaying the patient's oral intake. The mean length of the hospitalization was 21 days. CONCLUSIONS: The iTST provides a larger lumen unlimited by the size of the esophagus in cervical esophagogastric anastomosis. This technique is feasible, and sufficient short-term results have been achieved. Further studies with the accumulation of more cases will be required to prove the benefits of iTST for reconstruction after MIE.

Clinical Outcomes of Laparoscopic Versus Laparotomic Distal Gastrectomy in Gastric Cancer Patients: A Multilevel Analysis Based on a Nationwide Administrative Database in Japan.

BACKGROUND: The present study compared the short-term outcomes and costs of laparoscopic distal gastrectomy (LDG) with those of open distal gastrectomy (ODG) for gastric cancer using a nationwide administrative database in Japan. METHOD: Overall, 37,752 patients with gastric cancer who underwent distal gastrectomy at 1074 hospitals in the fiscal year 2012-2013 were evaluated using a diagnosis procedure combination database in Japan. We performed a retrospective analysis via a multilevel analysis (MLA) of the short-term surgical results and costs of the LDG and ODG groups. The models included the age, sex, comorbid complications, smoking, body mass index (BMI), activity of daily living (ADL), stage, and the number of cases of gastrectomy per facility for adjustment. The in-hospital mortality relative to the hospital volume was also compared. RESULTS: The LDG group required postoperative blood transfusion less frequently and had fewer postoperative complications, shorter hospitalization, and lower operative mortality than the ODG group. While this stage did not correlate with the in-hospital mortality, the surgical method, age, sex, ADL, BMI, comorbidity, and yearly volume showed a correlation. A significant association in the in-hospital mortality was observed between low- and very-high-volume hospitals. CONCLUSION: In this large nationwide cohort of patients with gastric cancer using an MLA, LDG was shown to be safer with lower mortality and postoperative complication rates than ODG.

Robotic-Assisted Distal Gastrectomy for Gastric Cancer Using an Oval-Shaped Port Device.

INTRODUCTION: This report describes the techniques and outcomes of robot-assisted distal gastrectomy (RDG) for gastric carcinoma using an oval-shaped port device. MATERIALS AND METHODS: A total of 15 patients underwent RDG with lymphadenectomy using the E‧Z Access/LAP-PROTECTOR oval-type device (Hakko Co., Ltd., Tokyo, Japan) performed by a single surgeon between 2018 and 2019. This device was introduced to the umbilicus under two settings, depending on the patient's figure. A horizontal setting (n=7) was used to reduce the number of trocar skin incisions in thin patients by placing a scope trocar and assist port within the E-Z Access. The vertical setting (n=8) was used for large and obese patients, enabling the endoscope position to move 50mm toward the cephalad side by rotating the device 180° to improve the surgical view of the suprapancreatic area ("dual port position" using the E‧Z Access oval-type device). The intracorporeal Billroth-I anastomosis or Roux-en-Y method was used for reconstruction. The short-term patient outcomes were determined to assess the safety and feasibility of our procedures. RESULTS: The E-Z Access oval-type device was useful for maintaining an optimal surgical field and reducing the number of skin incisions and the level of surgeon stress. Furthermore, its removal cap and wound protector allowed for an airtight seal, umbilical wound protection, and smooth specimen removal and re-pneumoperitoneum. R0 resection was accomplished in all cases without the need for conversion to open or conventional laparoscopic surgery. The median operating time was 323 (range, 245-590) minutes, and the median blood loss was 5ml. The median number of retrieved lymph nodes was 30. Neither major postoperative complication, including umbilical skin damage, nor postoperative mortality, was observed. The mean length of the hospitalization was 12.5 days. CONCLUSIONS: Our robotic approach using an oval-shaped port device for gastric cancer patients is feasible in terms of patient safety and curability.

[A Case of Carcinoma Showing Thymus-Like Differentiation (CASTLE) of the Thyroid].

The case presented herein was a 70-year-old woman who had no compliant, but had a mass in the lower part of the right lobe of the thyroid detected by ultrasound (US). The US image of the tumor, measuring 13 mm in diameter, showed a low and heterogeneous internal echo level with calcification and an irregular margin. The tumor appeared to extend to the adjacent sternothyroid muscle, and cervical lymph node swelling was detected in a computer tomography (CT) image, but no metastatic lesion was found by positron emission tomography (PET)-CT. In a fine needle aspiration cytology of the tumor, papillary thyroid carcinoma was suggested because of the atypical epithelial cells having some changes other than intranuclear inclusion bodies. A subtotal thyroidectomy and central neck lymph node dissection were performed. The excised tumor was histologically composed of irregular nests or sheets of atypical squamoid epithelial cells with some ductal structures that leached to the sternothyroid muscle and involved the right lower parathyroid gland. Carcinoma showing thymus-like differentiation (CASTLE) was diagnosed histopathologically and immunohistochemically with the following immunohistochemical results: Cluster of differentiation 5 (CD5) (+), tumor protein p63 (p63) (+), KIT proto-oncogene receptor tyrosine kinase (c-KIT(CD117)) (+), thyroglobulin (-), and thyroid transcription factor-1 (TTF-1) (-). CASTLE is a rare carcinoma of the thyroid that architecturally resembles thymic epithelial tumors. Many CASTLE patients have been misdiagnosed as other carcinomas, such as anaplastic carcinoma, poorly differentiated carcinoma or squamous cell carcinoma of the thyroid. Immunohistochemical examination, including CD5 played an important role in the final diagnosis of CASTLE, although the distinction from diagnosis as squamous cell carcinoma or mucoepidermoid carcinoma in Hematoxylin-Eosin staining was challenging in our case. Nodal metastasis and perithyroidal tumor extension of CASTLE can predict its worse prognosis. Thus, at least careful follow-up studies are mandatory in cases of CASTLE.

A Review of 7 Cases of Laparoscopic Cholecystectomy for Pediatric Cholecystolithiasis.

Pediatric cholecystolithiasis is a relatively rare disease, but it is recently increasing in Japan. Laparoscopic cholecystectomy (LC) is a standard procedure for cholecystolithiasis not only in adults but also in children, and we are aggressively introducing single-incision laparoscopic cholecystectomy (SILC) at our hospital. We reviewed the patient characteristics, operation procedures and outcomes of 7 children (15 years old and under) with cholecystolithiasis who underwent LC in our hospital between August 1995 and December 2015. The 7 patients included 5 males and 2 females, with a mean age of 8 years 6 months. Underlying diseases were found in 5 patients (cerebral palsy in 2 patients, pancreaticobiliary maljunction with common bile duct stones in 1, acute lymphocytic leukemia in 1, hereditary stomatocytosis in 1), and none were found in the other 2. LC (3 conventional LC and 2 SILC) was performed in 5 of the patients. Laparoscopic choledocholithotomy was performed in 1 patient and laparoscopic splenectomy (LS) was performed in 1 patient at the same time. The mean operative time in all the cases of LC was 108 (70-140) minutes (conventional LC 113 (70-140) min, SILC 100 (90-100) min). Intraoperative cholangiography was performed in 4 cases and omitted in 3 cases. The only postoperative complication was a wound infection in 1 patient. The umbilical skin incision length in the SILC was 2.0 cm. We conclude that LC can be safely performed for children with cholecsytolithiasis, and that SILC is feasible and advantageous in terms of its improved cosmesis.

A Case of Matrix-Producing Carcinoma of the Breast.

A 61-year-old woman was referred to our hospital because of a right breast mass. A 19 mm hard mass was palpable in the A area of the right breast. A contrast-enhanced MRI showed rim enhancement at the peripheral region of the tumor, which was thought to represent the carcinoma component mainly at the periphery and the matrix component inside the tumor. A low density mass with rim enhancement at the peripheral region was observed in a contrast-enhanced CT, the same as in the MRI. Neither axillary lymph node metastasis nor distant metastasis was observed. A core needle biopsy of the tumor lead to a diagnosis of matrix-producing carcinoma (MPC). A breast-conserving mastectomy with sentinel lymph nodes biopsy was performed on the right breast MPC (T1c, N0, M0 Stage I). Histopathologically, the tumor demonstrated overt carcinoma with direct transition to a cartilaginous or osseous matrix and lacked an intervening spindle cell component. Immunohistochemistry showed estrogen receptor (ER) (-), progesterone receptor (PgR) (-), human epidermal growth factor receptor 2 (HER2) (-), and Ki67 index of 50%, so-called triple negative breast cancer. The tumor was also positive for SRY-related HMG box-9 (SOX9), which is a useful marker of chondroid differentiation in normal and neoplastic tissues. The patient lived free from recurrence for 5 years, even though her adjuvant therapy was only radiation therapy without adjuvant chemotherapy. MPC is an uncommon and relatively rare variant of metaplastic carcinoma, and the prognosis for patients with MPC is poorer than that for patients with ordinary breast cancer. Here we report a case of MPC of the breast with characteristic rim enhancement in contrast-enhanced MRI and CT. The intrinsic subtype and prognosis of MPC is controversial, and then we may need more experience with MPC cases.

Laparoscopic approach for port site mass diagnosed as a Schloffer tumor following surgery of ascending colon cancer.

Schloffer tumor is a foreign body granuloma that develops in the subcutaneous layer of the abdomen over several months to several years after surgery due to sutures. Here, we performed a laparoscopic resection for a benign Schloffer tumor that showed positive F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) at the port site of a laparoscopic right hemicolectomy for advanced colon cancer. We report a case in which systemic chemotherapy was avoided as a result of the histological examination following the laparoscopic approach. A 66-year-old female, who underwent laparoscopic right hemi colectomy for stage IIIA ascending colon cancer, was revealed an enhanced mass at the right side of the abdominal subcutaneous layer. PET examination showed a high accumulation of FDG. Laparoscopic tumor resection was performed. Pathological findings reported the formation identical to the Schloffer tumor. Schloffer tumor, which is rare, should be considered as one of the differential diagnoses for tumor with FDG-PET positivity at the port site during the postoperative surveillance period of colorectal cancer.

Functional expression of double-stranded RNA-dependent protein kinase in rat intestinal epithelial cells.

Intestinal epithelial cells (IECs) are exposed to external environment, microbial and viral products, and serve as essential barriers to antigens. Recent studies have shown that IECs express Toll-like receptors (TLRs) and respond to microbial components. The antimicrobial and antiviral barriers consist of many molecules including TLRs. To investigate the further component of this barrier in intestine, we examined the expression of double-stranded RNA-dependent protein kinase (PKR). PKR is a player in the cellular antiviral response and phosphorylates alpha-subunit of the eukaryotic translation initiation factor 2 (eIF-2alpha) to block protein synthesis and induces apoptosis. In this study, we showed that the expression of PKR was restricted to the cytoplasm of absorptive epithelial cells in the intestine of adult rat. We also demonstrated that PKR was expressed in the cultured rat intestinal epithelial cells (IEC-6). The level of PKR protein expression and the activity of alkaline phosphatase (ALP) increased in the cultured IEC-6 cells in a time-dependent manner. Inhibition of PKR by the 2-aminopurine treatment decreased ALP activity in the IEC-6 cells. Treatment of IEC-6 cells with synthetic double-stranded RNA (dsRNA) induced cell death in a dose-dependent manner. The addition of hydrocortisone also provoked suppression of PKR expression and ALP activity. This modulation might be mediated by signal transducers and activators of transcription-1 (STAT-1) protein. We concluded that PKR is expressed in IECs as potent barriers to antigens and is a possible modulator of the differentiation of rat IECs.

An integrin-activating peptide, PHSRN, ameliorates inhibitory effects of conventional peritoneal dialysis fluids on peritoneal wound healing.

BACKGROUND: Bioincompatible peritoneal dialysis fluids (PDFs) cause pathological changes in the peritoneal membrane, related to membrane dysfunction and progressive peritoneal fibrosis. We investigated the effects of Pro-His-Ser-Arg-Asn (PHSRN) peptide, one of the fibronectin cell-binding domains that activates integrins and reinforces wound healing, on peritoneal remodelling in a rat peritoneal injury model undergoing peritoneal dialysis. METHODS: The peritoneal mesothelial monolayer was removed by a stripping procedure in rats receiving conventional high glucose-containing PDF supplemented with or without PHSRN or control His-Ser-Pro-Asn-Hrg (HSPNR) peptides. Effects of PHSRN on cell motility and signalling molecules were examined in cultured rat peritoneal mesothelial cells (RPMCs) and normal rat kidney fibroblasts (NRKs). RESULTS: The cytokeratin- and HBME-1-positive mesothelial cell monolayer was selectively removed by the procedure. By day 6, HBME-1-positive cells had regenerated to 53.3 +/- 6.5% of the peritoneal surface in the control group. Regeneration of the mesothelial layer was delayed in the PDF group (35.2 +/- 10.2%, P < 0.05), but PHSRN reversed the effects of PDF (51.7 +/- 9.6%, P < 0.05). PDF treatment increased thickening of granulomatous submesothelial tissue and numbers of ED1-, CD31- and alpha-smooth muscle actin-positive cells, but PHSRN ameliorated these effects. HSPNR had no effects on mesothelial regeneration or peritoneal wound healing. PHSRN, but not HSPNR, recovered glucose-induced inhibition of cell motility and phosphorylation of focal adhesion kinase and its downstream p130(Cas) in RPMCs and NRKs. CONCLUSIONS: These results suggest that PHSRN has beneficial effects on peritoneal regeneration by reducing the inhibitory effects of conventional PDF on integrin-mediated wound healing.

Synchronous occurrence of early neuroendocrine carcinoma and tubular adenocarcinoma in the stomach.

This report describes a patient with early neuroendocrine carcinoma (NEC) and tubular adenocarcinoma in the stomach. A 74-year-old Japanese male experienced epigastralgia. Endoscopic examination revealed two small lesions; one was an elevated lesion with ulceration at the posterior wall of the pre-pylorus and the other was a depressed lesion at the greater curvature of the antrum. Pathological diagnosis of the biopsies indicated poorly differentiated adenocarcinoma from the lesion on the pre-pylorus and well differentiated adenocarcinoma from the lesion on the antrum. He was referred to the surgical outpatient clinic with early double cancer of the stomach. A distal partial gastrectomy with lymph node dissection was performed. A histopathological examination revealed NEC at the lesion on the pre-pylorus and well differentiated tubular adenocarcinoma at the lesion on the antrum. These two lesions were completely separate from each other. Therefore, this case is thought to demonstrate the synchronous occurrence of early NEC and tubular adenocarcinoma in the stomach.