A case report of carcinoma of the papilla of Vater associated with a hyperplasia-dysplasia-carcinoma sequence by pancreaticobiliary maljunction.

BACKGROUND: Pancreaticobiliary maljunction (PBM) is a known risk factor for biliary tract cancer. However, its association with carcinoma of the papilla of Vater (PVca) remains unknown. We report a case with PVca that was thought to be caused by the hyperplasia-dysplasia-carcinoma sequence, which is considered a mechanism underlying PBM-induced biliary tract cancer. CASE PRESENTATION: A 70-year-old woman presented with white stool and had a history of cholecystectomy for the diagnosis of a non-dilated biliary tract with PBM. Esophagogastroduodenoscopy revealed a tumor in the papilla of Vater, and PVca was histologically proven by biopsy. We finally diagnosed her with PVca concurrent with non-biliary dilated PBM (cT1aN0M0, cStage IA, according to the Union for International Cancer Control, 8th edition), and subsequently performed subtotal stomach-preserving pancreaticoduodenectomy. Pathological findings of the resected specimen revealed no adenomas and dysplastic and hyperplastic mucosae in the common channel slightly upstream of the main tumor, suggesting a PBM related carcinogenic pathway with hyperplasia-dysplasia-carcinoma sequence. Immunostaining revealed positivity for CEA. CK7 positivity, CK20 negativity, and MUC2 negativity indicated that this PVca was of the pancreatobiliary type. Genetic mutations were exclusively detected in tumors and not in normal tissues, and bile ducts from formalin-fixed paraffin-embedded samples included mutated-ERBB2 (Mutant allele frequency, 81.95%). Moreover, of the cell-free deoxyribonucleic acid (cfDNA) extracted from liquid biopsy mutated-ERBB2 was considered the circulating-tumor deoxyribonucleic acid (ctDNA) of this tumor. CONCLUSIONS: Herein, we report the first case of PVca with PBM potentially caused by a "hyperplasia-dysplasia-carcinoma sequence" detected using immunostaining and next-generation sequencing. Careful follow-up is required if pancreaticobiliary reflux persists, considering the possible development of PVca.

World-first report of low anterior resection for rectal cancer with the hinotori™ Surgical Robot System: a case report.

BACKGROUND: The hinotori™ Surgical Robot System was approved for use in colorectal cancer surgery in Japan in 2022. This robot has advantages, such as an operation arm with eight axes, an adjustable arm base, and a flexible three-dimensional viewer, and is expected to be utilized in rectal cancer surgery. Herein, we report the world's first surgery for rectal cancer using the hinotori™ Surgical Robot System. CASE PRESENTATION: A 71-year-old woman presented to our hospital with bloody stools. A colonoscopy revealed type 2 advanced cancer in the rectum, and a histological examination exposed a well-differentiated adenocarcinoma. Abdominal enhanced computed tomography divulged rectal wall thickening without significant swelling of the lymph nodes or distant metastasis. Pelvic magnetic resonance imaging showed tumor invasion beyond the intrinsic rectal muscle layer. The patient was diagnosed with cStage IIa (cT3N0M0) rectal cancer and underwent low anterior resection using the hinotori™ Surgical Robot System. Based on an adequate simulation, surgery was safely performed with appropriate port placement and arm base-angle adjustment. The operating time was 262 min, with a cockpit time of 134 min. Subsequently, the patient was discharged 10 days postoperatively without complications. The pathological diagnosis was pStage IIA (cT3N0M0) and the circumferential resection margin was 6 mm. CONCLUSIONS: We report the first case of low anterior resection for rectal cancer using the hinotori™ Surgical Robot System, in which a safe and appropriate oncological surgery was performed.

Right hemicolectomy for ascending colon cancer using the hinotori surgical robot system: The first ever case report for colon cancer.

The hinotori Surgical Robot System obtained pharmaceutical approval for use in colorectal cancer surgery in October 2022 in Japan, and its advantages, including its operating arm with eight axes, adjustable arm base, and flexible 3D viewer, are expected to be utilized in colon cancer surgery. A 68-year-old woman presented to our hospital with abdominal pain and was diagnosed with cStageIIa (cT3N0M0) ascending colon cancer and underwent right hemicolectomy using the hinotori Surgical Robot System with the appropriate port placement on the arc around the hepatic flexure, which was available for both ileocecal manipulation and lymph node dissection, and adjustment of the angle of the arm base to further reduce interference. Herein we report the world's first surgery for colorectal cancer using the hinotori Surgical Robot System.

Development of an ultralow-latency communication system using shared internet access: promoting the implementation of telemedicine.

Telemedicine is becoming increasingly important to address the shortage of gastrointestinal surgeons and disparities in domestic and international treatment outcomes for patients with colorectal cancer. The development of a low-latency communication system using existing communication infrastructure (shared internet access: SIA) is necessary to promote the use of telemedicine. The aim of this study was to develop a low-latency communication system using SIA. We conducted an experiment between Sapporo and Tokyo using an ultralow-latency communication system for remote medical education (TELEPRO®). The latency was measured using 2000 annotations from a monitor in Sapporo, which confirmed a median latency of 27.5 ms. A low-latency communication system based on SIA with latency lower than the maximum allowable latency for telemedicine was developed successfully.

Artificial intelligence-based technology to make a three-dimensional pelvic model for preoperative simulation of rectal cancer surgery using MRI.

Aim: A new technique that allows visualization of whole pelvic organs with high accuracy and usability is needed for preoperative simulation in advanced rectal cancer surgery. In this study, we developed an automated algorithm to create a three-dimensional (3D) model from pelvic MRI using artificial intelligence (AI) technology. Methods: This study included a total of 143 patients who underwent 3D MRI in a preoperative examination for rectal cancer. The training dataset included 133 patients, in which ground truth labels were created for pelvic vessels, nerves, and bone. A 3D variant of U-net was used for the network architecture. Ten patients who underwent lateral lymph node dissection were used as a validation dataset. The correctness of the vascular labelling was assessed for pelvic vessels and the Dice similarity coefficients calculated for pelvic bone. Results: An automatic segmentation algorithm that extracts the artery, vein, nerve, and pelvic bone was developed, automatically producing a 3D image of the entire pelvis. The total time needed for segmentation was 133 seconds. The success rate of the AI-based segmentation was 100% for the common and external iliac vessels, but the rates for the vesical vein (75%), superior gluteal vein (60%), or accessory obturator vein (63%) were suboptimal. Regarding pelvic bone, the average Dice similarity coefficient between manual and automatic segmentation was 0.97 (standard deviation 0.0043). Conclusion: Though there is room to improve the segmentation accuracy, the algorithm developed in this study can be utilized for surgical simulation in the treatment of advanced rectal cancer.

Laparoscopic mesh repair and Toupet fundoplication for parahiatal hernia complicated by sliding hiatal hernia: A case report.

INTRODUCTION: The parahiatal hernia is a rare type of diaphragmatic hernia in adults. Although there have been occasional reports of parahiatal hernias, few have reported simultaneous laparoscopic mesh repair of a parahiatal hernia with a hiatal hernia. This report describes laparoscopic mesh repair and fundoplication for a parahiatal hernia combined with an esophageal hiatal hernia. PRESENTATION OF CASE: A 39-year-old woman presented with left-side postprandial abdominal pain. Esophagogastroduodenoscopy revealed a parahiatal hernia and sliding hiatal hernia. Computed tomography (CT) showed that the stomach had prolapsed into the thorax from the outside of the left diaphragm. The preoperative diagnosis was parahiatal hernia with a hernial sac complicated by sliding hiatal hernia. Laparoscopic mesh repair was planned. The stomach had prolapsed on the left side of the esophagus and was extruded. The diagnosis of a parahiatal hernia with a hernial sac complicated by a sliding hiatal hernia was confirmed. The esophageal hiatal hernia was repaired using two non-absorbable sutures. The congenital defect was further reinforced with mesh fixed to the orifice of the adjacent parahiatal hernia. We performed Toupet fundoplication to treat gastroesophageal reflux disease and sutured the right diaphragmatic crus and stomach to prevent migration. The patient was discharged home on postoperative day 5. CONCLUSION: We encountered a patient with a parahiatal hernia complicated by a sliding hiatal hernia. The parahiatal hernia can be diagnosed by CT imaging. Preoperative diagnostic imaging can lead to appropriate treatment.

Defecation disorder and anal function after surgery for lower rectal cancer in elderly patients.

AIM: This study aims to investigate the association of patient age with defecation disorders and anal function after lower rectal cancer surgery. METHODS: We retrospectively reviewed the data of 141 consecutive patients with lower rectal cancer who underwent sphincter-preserving operation. The patients were classified into five categories by age thresholds at 65, 70, 75, 80, and 85 years, for disaggregate analysis. Anal manometry was used for measuring the maximum resting pressure, high-pressure zone, and maximum squeeze pressure. Anal manometry was performed preoperatively and at 3, 6, 9, and 12 months postoperatively. The Wexner and low anterior resection syndrome scores were assessed at 1, 3, 6, 9, and 12 months after rectal surgery or stoma closure for patients with ileostomy. RESULTS: The data of 117 patients were reviewed. No significant differences were found between the younger and elderly groups in any characteristics across the six age groups. The preoperative intra-anal pressures of the elderly patients were slightly lower than those of the younger patients; however, there was no significant difference in the course of postoperative intra-anal pressures. Defecation disorder, as measured by the Wexner and low anterior resection syndrome scores, improved significantly in elderly patients compared to younger patients. CONCLUSION: There was no significant difference in the course of postoperative intra-anal pressures between the elderly and younger patients. However, defecation disorders in elderly patients significantly improved compared with younger patients. Sphincter-preserving operation can be a viable treatment option for active elderly patients.

Short-Term Outcomes with Standardized Transperineal Minimally Invasive Abdominoperineal Excision for Rectal Cancer.

BACKGROUND: Transperineal abdominoperineal excision (TpAPE) is an emerging approach for low rectal cancers but is technically challenging. Based on an anatomical study we conducted previously, we have standardized the TpAPE procedure. Here, we aimed to validate the feasibility of the standardized TpAPE by investigating the short-term outcomes. METHODS: From January 2018 to November 2020, a total of 405 patients underwent laparoscopic or robotic rectal resection for rectal cancer in our institution. For the current study, we analyzed data for the 31 patients who underwent TpAPE. The abdominal phase was performed synchronously with the perineal phase using either a laparoscopic or robotic approach. Short-term outcomes included operative and pathological results. RESULTS: Of the 31 cases, we identified anterior quadrant tumor invasion in 21. Most of the cases were advanced, with 6 staged as cT3 and 20 as T4. Of the 27 cases not involving distant metastasis, neoadjuvant therapy was performed in 19. No inadvertent rectal perforation or urethral injury was found intraoperatively. The median procedural duration to specimen removal was 250 min (interquartile range, 204-287), and the median intraoperative blood loss was 10 ml (interquartile range, 5-40). Regarding postoperative complications, perineal wound infection developed in 11 cases. A positive circumferential resection margin was found in 3, corresponding to the positive rate of 9.7%. These three cases were among the first 12 cases involving standardized TpAPE. CONCLUSIONS: The current results indicate that TpAPE can be performed safely and might represent a useful option for low rectal cancer resection.

A modified method for resected specimen processing in rectal cancer: Semi-opened with transverse slicing for measuring of the circumferential resection margin.

Circumferential resection margin (CRM) is essential for oncological quality assessment in rectal cancer surgery. CRM represents a surrogate parameter for oncological outcomes and is important for stratifying treatment strategies in Western nations. In Japan, the mesentery is removed for specimen processing in order to extract as many lymph nodes (LNs) as possible; consequently, CRM cannot be measured. Given the diversification of treatment strategies for rectal cancer, the lack of measurement of CRM to assess surgical outcomes is a crucial issue that must be resolved. Therefore, it is necessary to establish a method enabling measurement of CRM while enjoying the advantages of the Japanese method. In the method we developed, the mesentery is removed from the rectum more than 2 cm away from the tumor, and the vicinity of the tumor is circularized. It is necessary to investigate the usefulness of this method prospectively in a multi-center study.

Laparoscopic low anterior resection for rectal cancer wherein the inferior mesenteric artery arose from the superior mesenteric artery: a case report.

BACKGROUND: Few cases have been reported of colorectal cancer with inferior mesenteric artery (IMA) branching abnormalities; therefore, the lymphatic flow in such cases remains unknown. We report the first case of locally advanced rectal cancer in which the IMA arose from the superior mesenteric artery (SMA) in which we achieved to visualize the lymphatic flow. CASE PRESENTATION: A 65-year-old woman complaining of bloody stools was investigated in our hospital and suspected with rectal cancer. Colonoscopy and abdominal enhanced computed tomography (CT) revealed a circumscribed, localized ulcerative tumor in the rectum. 3-Dimensional contrast-enhanced computed tomography (3D-CT) showed that the IMA arose from the SMA. The patient was diagnosed with rectal cancer (cT3N0M0, cStage IIa) and laparoscopic low anterior resection was performed. The sigmoid colon was resected using the medial approach. Only the plexus of the colic branch of the lumbar splanchnic nerve was observed at the site where the root of the IMA usually exists and showed interruption of the indocyanine green (ICG) fluorescence-illuminated lymphatics. The root of the IMA was ligated, and Japanese D3 lymphadenectomy was performed, preserving the accessory middle colic artery. All fluorescent lymph nodes were resected. The pathological diagnosis was pT4aN1aM0 stage IIIb. The patient's postoperative course was uneventful. Adjuvant chemotherapy was administered, and the patient was recurrence-free at 1.5 years after surgery. CONCLUSIONS: We were able to perform safe and appropriate surgery oncologically, despite abnormal vascular anatomy, due to preoperative identification using 3D-CT and intraoperative navigation using ICG administration.

MRI-detected extramural vascular invasion potentiates the risk for pathological metastasis to the lateral lymph nodes in rectal cancer.

PURPOSE: Multidisciplinary treatment for locally advanced rectal cancer requires an accurate assessment of the risk of metastasis to the lateral lymph nodes (LNs). We herein aimed to stratify the risk of pathological metastasis to lateral LNs based on the preoperatively detected malignant features. METHODS: All patients with rectal cancer who underwent surgery from January 2016 to July 2020 were identified. We recorded the TNM factors; perirectal and lateral LN sizes; and MRI findings, including mesorectal fascia involvement, extramural vascular invasion (EMVI), tumor site, and tumor distance from the anal verge. RESULTS: 101 patients underwent rectal resection with lateral lymph node dissection, of whom 16 (15.8%) exhibited pathological metastases to the lateral LNs. Univariate analyses demonstrated that lateral LN metastasis was significantly correlated with mrEMVI positivity (p = 0.0023) and a baseline lateral LN short-axis length of ≥ 5 mm (p < 0.0001). These significant associations were confirmed by a multivariate analysis (p = 0.0254 and 0.0027, respectively). The lateral LN metastasis rate was as high as 44% in cases bearing both risk factors, compared to 0% in cases lacking both risk factors. CONCLUSION: The results elucidated in this study may contribute to risk stratification, which can be used when determining the indications for lateral lymph node dissection.

Transperineal minimally invasive abdominoperineal excision for rectal cancer based on anatomical analysis of the muscular structure.

INTRODUCTION: Transperineal minimally invasive abdominoperineal excision (TpAPE) may help minimize surgical invasiveness and make it possible to perform two-team surgery, although this procedure is regarded as difficult. The anatomical structures are complicated and have not been clearly defined, particularly on the anterior side of the anorectal junction in men. We investigated the anatomical configuration around the anterior wall of the anorectal junction, focusing on the structure of the striated muscles, to establish a standard procedure for TpAPE. METHODS: We scrutinized the T2 -weighted MRI scans of 106 men, and two male cadavers were used to examine the muscular structure surrounding the anorectal junction. We established our standardized procedure for TpAPE based on these anatomical studies. We also analyzed the clinicopathological findings from five men who had undergone TpAPE at our institution. RESULTS: Using MRI, we detected band-like muscles bilaterally, just medial to the puborectal muscle in all analyzed patients, which we termed the rectal anterolateral muscle. We also detected the muscles that may correspond to the rectal anterolateral muscle when inspecting the cadavers. The standardized TpAPE procedures were carried out uneventfully for the five cases, and intraoperative complications such as urethral injury and inadvertent rectal perforation did not occur. CONCLUSION: We standardized the TpAPE procedure based on anatomical examination of the muscular structure around the anal canal. The findings can contribute to safe implementation of TpAPE.

Arteriovenous malformation in the pancreatic head initially mimicking a hypervascular mass treated with duodenum-preserving pancreatic head resection: a case report.

BACKGROUND: The mainstay treatment for arteriovenous malformation in the pancreatic head (Ph-AVM) is standard pancreatectomy, especially pancreaticoduodenectomy (PD), or interventional endovascular treatment. We report the first case of Ph-AVM treated with duodenum-preserving pancreatic head resection (DPPHR) performed to preserve the periampullary organs. CASE PRESENTATION: A 59-year-old man presenting with back pain underwent contrast-enhanced computed tomography followed by angiography of the anterior superior pancreaticoduodenal artery. He was diagnosed with Ph-AVM and indicated for DPPHR with preservation of the periampullary organs; Ph-AVM's benign nature seldom requires lymph node dissection. During the operation, the right colon was mobilized and the omental bursa was released to expose the periampullary structures. The pancreas was transected just above the superior mesenteric vein. The inferior pancreaticoduodenal artery and papillary arteries branching from the posterior superior pancreaticoduodenal artery were carefully preserved to maintain the blood flow to the lower bile duct and papilla of Vater. The remnant pancreas was reconstructed with pancreaticogastrostomy using the modified Blumgart method. Pathological examination of the resected specimen revealed an irregular course of the arteries and veins concomitant with marked dilation throughout the pancreatic head. The patient was pathologically diagnosed with Ph-AVM. He developed hematemesis caused by a rupture of the pseudoaneurysm on postoperative day 20 and underwent coil embolization. A bilio-enteric fistula and stenosis of the common bile duct were found and treated by placement of an endoscopic biliary stent. At the 8-month follow-up, the Ph-AVM had not recurred. CONCLUSIONS: Compared to PD, DPPHR confers the clinical benefit of preserving the periampullary organs, although further studies are needed to confirm this. Therefore, the choice of this procedure should be based on the surgical morbidities and long-term outcome of the patient.

Safety and efficacy of mucous fistula refeeding in low-birth-weight infants with enterostomies.

PURPOSE: To investigate the safety and efficacy of mucous fistula refeeding (MFR) in low-birth-weight infants. METHODS: Between December 2006 and December 2018, medical records of low-birth-weight infants who underwent small bowel enterostomy formation in the neonatal period and subsequent stoma closure at our institution were retrospectively reviewed. Patients were assigned to "refeeding" (RF) and "non-refeeding" (NRF) groups, which were compared for patient characteristics and clinical outcomes. We also cultured the proximal stoma output over time in the RF group and reviewed changes in the flora to evaluate the safety of refeeding. RESULTS: In the RF group, compared with that before refeeding, there was significantly more rapid weight gain after refeeding (17.7 vs 10.6 g/day; P = 0.002). Median total time of parenteral nutrition (PN) was 25 and 87 days in the RF and NRF groups, respectively (P = 0.001). The number of patients who developed PN-associated liver disease (PNALD) was smaller in the RF group (P = 0.12). No complications of MFR were noted and no pathogenic bacteria were cultured. CONCLUSION: MFR was able to diminish the need for PN, which potentially decreased the incidence of PNALD, and was safe as there were no complications of the refeeding process.

Recurrent intestinal ischemia following surgery for gastric and duodenal perforations: a case report.

BACKGROUND: Extremely low birth weight (ELBW) is a risk factor for various gastrointestinal complications. In the recent decades, advances in medicine have increased the survival of ELBW infants with necrotizing enterocolitis (NEC). To our knowledge, there have been no reports of neonates or infants developing simultaneous gastric and duodenal perforations and later developing NEC. We report a case of an extremely low birth weight infant (ELBWI) who developed both gastric and duodenal perforations at the same time and developed NEC after operation for gastric and duodenal perforations. CASE PRESENTATION: The patient was a female infant with ELBW who developed both gastric and duodenal perforations at the same time and developed NEC after operation for gastric and duodenal perforations. After birth, endotracheal intubation was performed. However, barotrauma occurred during positive pressure ventilation, resulting in a large area of emphysema in the left lower lung field, leading to collapse of the left lung. This giant bulla may have compressed the pulmonary vein, possibly resulting in pulmonary venous thrombosis (PVT). This episode could have triggered simultaneous gastric and duodenal perforations. In addition, we hypothesized that PVT caused acute arterial ischemia, leading to the development of NEC. The infant was started on heparin for anticoagulation. Later, the infant developed non-immunoglobulin E (IgE)-mediated gastrointestinal food allergies (non-IgE-GI-FAs). The giant bulla associated with barotrauma might have caused PVT, resulting in arterial emboli and multiple simultaneous gastrointestinal perforations. CONCLUSIONS: Anticoagulation therapy with heparin for acute arterial thrombosis is effective for preventing the development of short bowel syndrome. Duodenal and intestinal surgery probably acted as risk factors for the subsequent development of non-IgE-GI-FAs. The infant had been stabilized at the time of writing this report.

Neonates undergoing gastrointestinal surgery have a higher incidence of non-IgE-mediated gastrointestinal food allergies.

PURPOSE: We aimed at investigating the incidence and risk factors of non-IgE-mediated gastrointestinal food allergies (non-IgE-GI-FAs) in neonates and infants. METHODS: A total of 126 infants who underwent neonatal gastrointestinal surgeries were grouped into those with (n = 13) and those without an onset of non-IgE-GI-FAs (n = 113). The characteristics of the two groups (e.g., birth weight, delivery type, small intestinal surgeries, and pre-/postoperative nutrition) were compared. Small intestinal surgeries were classified into those with and those without full-layer invasion of the small intestine. For the statistical analysis, postoperative nutrition was classified into breast milk only, formula milk, and elemental diet only. RESULTS: Except for full-layer surgical invasion of the small intestine and the period of parenteral nutrition, no significant differences were found between the two groups. Surgery with full-layer invasion was a risk factor of non-IgE-GI-FAs (odds ratio (OR) 10.70, 95% confidence interval (95% CI) 2.11-54.20; p = 0.004). Formula milk after surgery was a risk factor of non-IgE-GI-FAs when compared to breast milk (OR 5.65, 95% CI 1.33-24.00; p = 0.019). CONCLUSION: Neonates undergoing gastrointestinal surgery have a higher incidence of non-IgE mediated gastrointestinal food allergies. We recommend that formula milk should not be administered to newborns who underwent neonatal gastrointestinal surgeries with full-layer invasion of the small intestine.