A case of robot-assisted resection for cecum cancer with anomalous venous confluence.

There are many reports on the positional relationship between the ileocolic artery and superior mesenteric vein (SMV). However, there have been no reports of anomalous venous confluence in the ileocecal vessel area. A 69-year-old man was diagnosed with cecal cancer on a preoperative examination of a lung tumor. We planned to perform surgery for the cecal cancer. Computed tomography angiography revealed an anomalous vein confluence in the ileocolic region. We performed robot-assisted ileocecal resection. Although the small intestinal vein was misidentified as the SMV at first, we confirmed the misidentification, identified the SMV on the dorsal side of the ileocolic artery, and ligated the ileocolic vessels with precise forceps manipulation during robotic surgery. Especially for cases with vascular anomalies revealed by preoperative computed tomography angiography, robotic surgery may be useful, as flexible forceps manipulation prevents vascular injury.

Gastrointestinal bleeding due to obstruction of the superior mesenteric vein.

ABSTRACT: Gastrointestinal bleeding is a common clinical symptom. Finding the underlying cause is the first step for treatment. In a few patients, this can be difficult. The present work reports on the unusual case of a 53-year-old man who presented gastrointestinal bleeding. No bleeding site was found by gastrocolonoscopy or interventional examination, but after multidisciplinary consultation, we discovered that the cause of gastrointestinal bleeding was the obstruction of the upper mesenteric vein.

Jejunal vein tributary analysis and intraoperative clamp testing in avoiding congestion after pancreatoduodenectomy.

PURPOSE: Although venous drainage of the jejunal loop may be maintained after sacrifice of jejunal vein tributaries during pancreatoduodenectomy, risk of severe jejunal mesenteric congestion following division of these tributaries can be difficult to predict. This study considered how best to predict safety of jejunal vein tributary dissection. METHODS: Preoperative imaging findings and results of intraoperative clamp tests of jejunal vein tributaries during pancreatoduodenectomy were analyzed in 121 patients with hepatobiliary and pancreatic disease to determine whether this information adequately predicted safety of resecting superior mesenteric vein branches. RESULTS: Jejunal vein tributaries caudal to the inferior border of the pancreatic uncinate process tended to be fewer when tributaries cranial to this landmark were more numerous. Tributaries cranial to the border drained a relatively wide expanse of jejunal artery territory in the jejunal mesentery. The territory of jejunal tributaries cranial to the inferior border of the pancreas did not vary according to course of the first jejunal vein branch relative to the superior mesenteric artery. One patient among 30 (3%) who underwent intraoperative clamp tests of tributaries cranial to the border showed severe congestion in relation to a venous tributary coursing ventrally to the superior mesenteric artery. CONCLUSION: Jejunal venous tributaries drained an extensive portion of jejunal arterial territory, but tributaries located cranially to the inferior border of the pancreas could be sacrificed without congestion in nearly all patients. Intraoperative clamp testing of these tributaries can identify patients whose jejunal veins must be preserved to avoid congestion.

Single-Dose enoxaparin for portomesenteric venous thrombosis prophylaxis after sleeve gastrectomy.

Introduction: Portomesenteric venous thrombosis (PMVT) may complicate sleeve gastrectomy. We believe that single dose of enoxaparin postoperatively can reduce the risk of PMVT. Objective: The objective was to study the outcomes of enoxaparin single dose compared to other perioperative prophylactic doses in preventing PMVT. Methods: Participants included 590 patients who underwent laparoscopic sleeve gastrectomy (LSG). These retrospective cohort data were collected from patient medical charts after bariatric surgery. Patients were followed up in the close postoperative period and at 1, 3, 6, 12, and 18 months. Descriptive statistical analysis was carried out. The objective was to estimate the incidence of PMVT with postoperative single 40 mg subcutaneous enoxaparin prophylactic regimen. Results: From January 2017 to December 2021, 590 patients with obesity underwent LSG. Five patients developed PMVT with an estimate incidence of 0.85%. Three patients had unexplained tachycardia and three patients had postoperative bleeding. Conclusions: Single-dose enoxaparin 40 mg is an effective thrombosis prophylaxis without increasing risk of bleeding.

Résumé Introduction: La thrombose veineuse portomésentérique (TVPM) peut compliquer la gastrectomie en manchon. Nous pensons qu'une dose unique d'énoxaparine en postopératoire peut réduire le risque de PMVT. Objectif: L'objectif était d'étudier les résultats de la dose unique d'énoxaparine par rapport à d'autres doses prophylactiques périopératoires dans la prévention de la PMVT. Méthodes: Les participants comprenaient 590 patients ayant subi une gastrectomie laparoscopique en manchon (LSG). Ces données de cohorte rétrospectives ont été collectées à partir des dossiers médicaux des patients après une chirurgie bariatrique. Les patients ont été suivis dans la période postopératoire étroite et à 1, 3, 6, 12 et 18 mois. Une analyse statistique descriptive a été réalisée. L'objectif était d'estimer l'incidence de la PMVT avec un régime prophylactique postopératoire unique d'énoxaparine sous-cutanée de 40 mg. Résultats: De janvier 2017 à décembre 2021, 590 patients obèses ont subi une LSG. Cinq patients ont développé une PMVT avec une incidence estimée à 0,85 %. Trois patients présentaient une tachycardie inexpliquée et trois patients présentaient des hémorragies postopératoires. Conclusions: Une dose unique d'énoxaparine de 40 mg est une prophylaxie efficace contre la thrombose sans augmenter le risque de saignement. Mots-clés: Énoxaparine, gastrectomie laparoscopique en manchon, thrombose veineuse portomésentérique prophylaxie, thromboembolie veineuse.

Robotic True D3 Lymph Node Dissection With Superior Mesenteric Vein-Taping Technique for Right-Sided Colon Cancer.

BACKGROUND: D3 is unaffected by anatomic factors even when the ileocolic artery runs along the dorsal side of the superior mesenteric vein. Complete "true D3" lymph node dissection in minimally invasive surgery for right-sided colon cancer could be beneficial for certain patients with lymph node metastases. IMPACT OF INNOVATION: The study aimed to determine the safety and feasibility of robotic true D3 lymph node dissection for right-sided colon cancer using a superior mesenteric vein-taping technique. TECHNOLOGY, MATERIALS, AND METHODS: The superior mesenteric vein was slowly and gently separated from the surrounding tissues and taped. Lifting the tape with the robotic third arm and fixing it in place using rock-stable tractions provides a good surgical view, which cannot otherwise be obtained. As a result, the ileocolic artery that branches from the superior mesenteric artery can be accurately exposed. Handling of the taping then enables expansion to a different surgical view. As the lymph nodes are originally concealed on the dorsal side of the superior mesenteric vein, this technique provides a good view for lymph node dissection. The root of the ileocolic artery was clipped and separated, and true D3 was thus completed. PRELIMINARY RESULTS: Fourteen patients underwent robotic true D3 lymph node dissection for right-sided colon cancer. No Clavien-Dindo classification grade II or higher intraoperative or postoperative complications were observed. The 30-day mortality rate was 0%. CONCLUSIONS: Our robotic true D3 lymph node dissection with superior mesenteric vein-taping technique is considered safe and feasible; it might be a promising surgical procedure for treating advanced right-sided colon cancer. FUTURE DIRECTIONS: Even when the ileocolic artery runs along the dorsal aspect of the superior mesenteric vein, the technique seems promising for facilitating robotic D3 lymph node dissection.

Mesenteric Vein Thrombosis following Sleeve Gastrectomy: A Case Report and Review of the Literature.

INTRODUCTION: Acute mesenteric ischemia (AMI) is a rare but lethal disease. Mesenteric vein thrombosis (VAMI) is a subtype of AMI. Morbid obesity is usually accompanied by hypertension, hyperlipidemia, or diabetes mellitus, which are risk factors associated with AMI. CASE PRESENTATION: We present a 28-year-old man with VAMI post-laparoscopic sleeve gastrectomy. He was first misdiagnosed with intestinal obstruction. Superior VAMI was confirmed after computed tomography angiography. Laparotomy, resection of the necrotic small bowel, and ostomy were performed immediately. CONCLUSION: Patients with morbid obesity accompanied by hypertension, hyperlipidemia, or diabetes mellitus have a high risk of AMI. Abdominal pain with sudden onset should be considered AMI. Anticoagulation therapy post-sleeve gastrectomy might help reduce the incidence of AMI.

Routine extended (30 days) chemoprophylaxis for patients undergoing laparoscopic sleeve gastrectomy may reduce Portomesenteric vein thrombosis rates.

BACKGROUND: Venous thromboembolism (VTE), including Portomesenteric vein thrombosis (PMVT), is a major complication of sleeve gastrectomy (SG). We changed our practice in July 2021 to routinely discharge all SG patients postoperatively with extended chemoprophylaxis for 30 days. OBJECTIVES: Evaluate the efficacy and safety of routine extended chemoprophylaxis compared to 2 prior timeframes using selective extended chemoprophylaxis. SETTING: University Hospital. METHODS: Between 2012-2018, SG patients were discharged on extended chemoprophylaxis for patients deemed "high-risk" for VTE, including patients with body mass index (BMI) >50, and previous VTE. Between 2018-2021, extended chemoprophylaxis was broadened to include patients with positive preoperative thrombophilia panels (including Factor VIII). After 2021, all SG were routinely discharged on extended chemoprophylaxis. The typical regimen was 30 days Lovenox BID (40-mg twice daily for BMI> 40, 60-mg twice daily for BMI >60). Outcomes evaluated were rate of VTE/PMVT and postoperative bleed, including delayed bleed. RESULTS: A total of 8864 patients underwent SG. Average age and BMI were 37.5 years and 43.0 kg/m2, respectively. The overall incidence of PMVT was 33/8864 (.37%). Converting from selective extended chemoprophylaxis (Group 1) to routine extended chemoprophylaxis (Group 3) decreased the rate of PMVT from .55% to .21% (P = .13). There was a significantly higher overall bleeding rate (.85%), including delayed bleeds (.34%) in the routine extended chemoprophylaxis patients (P < .05). These bleeds were mainly managed nonoperatively. CONCLUSIONS: Routine extended (30 day) chemoprophylaxis for all SG may reduce PMVT rate but lead to a higher bleeding rate post-operatively. The vast majority of the increased bleeds are delayed and can be managed non-operatively.

Intravascular placement and migration of a colonic stent into the inferior mesenteric vein.

Colonic self-expanding metal stents (SEMSs) are commonly used to treat large bowel obstruction due to gastrointestinal malignancy with great success. While mortality is negligible, morbidity from both early and late complications can be significant. Stent perforation, erosion and migration are the most feared complications. We present the first reported case of wire-associated colon perforation with placement and migration of an SEMS into the inferior mesenteric vein (IMV). A man in his early 60s presented with a large bowel obstruction due to a colorectal mass. He underwent endoscopic colonic SEMS placement for colonic decompression. The stent was later found to be within the IMV, requiring a colon resection and retrieval of the stent.

Three-dimensional Computed Tomography Evaluation of the Vasculature of Right-side Colon Cancer.

BACKGROUND/AIM: From an oncological perspective, central ligation of the feeding vessel is an important approach to consider when performing colon cancer surgery. This study aimed to use three-dimensional computed tomography (3D-CT) to clarify the vascular anatomy for performing central vascular ligation to improve the accuracy of minimally invasive surgery (MIS) performed to treat advanced right-side colon cancer. PATIENTS AND METHODS: This descriptive study was conducted at one institution and targeted 92 patients with right-side colon cancer whose vascular anatomy was evaluated with 3D-CT before surgery between January 2014 and December 2020 at Tokyo Medical University Hospital. RESULTS: In 49 patients (53.3%), the ileocolic artery was ventral to the superior mesenteric vein (SMV), whereas in 43 patients (46.7%), it was dorsal to the SMV. The right colic artery was present in 31 patients (33.7%). The middle colic artery was present in all patients (100%). A common duct type was present in 80 patients (87.0%). Branching directly from the superior mesenteric artery without a common duct was observed in 12 patients (13.0%). Twenty-one patients (22.9%) had an accessory superior mesenteric artery. CONCLUSION: The vascular structure of the right-side colon is highly complex. Conducting 3D-CT evaluations of the vessel anatomy is very useful for surgeons who conduct MIS, and is considered to enable central ligation to be performed safely and improve the quality of surgery, which will benefit patients.

Superior mesenteric vein/portal vein contact in preoperative imaging indicates biological malignancy in anatomically resectable pancreatic cancer.

BACKGROUND: Pancreatic cancer in contact with the superior mesenteric vein/portal vein is classified as resectable pancreatic cancer; however, the biological malignancy and treatment strategy have not been clarified. METHODS: Data from 186 patients who underwent pancreatectomy for pancreatic cancer were evaluated using a prospectively maintained database. The patients were classified as having resectable tumors without superior mesenteric vein/portal vein contact and with superior mesenteric vein/portal vein contact of ≤180°. Disease-free survival, overall survival, and prognostic factors were analyzed. RESULTS: In the univariate analysis, superior mesenteric vein/portal vein contact in resectable pancreatic cancer was a significant prognostic index for disease-free survival and overall survival. In the multivariate analysis for poor disease-free survival, the superior mesenteric vein/portal vein contact remained significant (hazard ratio = 2.13, 95% confidence interval: 1.29-3.51; p < 0.01). In the multivariate analysis, superior mesenteric vein/portal vein contact was a significant independent prognostic index for overall survival (hazard ratio = 2.17, 95% confidence interval: 1.27-3.70; p < 0.01), along with sex, tumor differentiation, nodal involvement, and adjuvant chemotherapy. Portal vein resection for superior mesenteric vein/portal vein contact did not improve the overall survival (p = 0.86). CONCLUSIONS: Superior mesenteric vein/portal vein contact in resectable pancreatic cancer was found to be an independent predictor of disease-free survival and overall survival after elective resection. Thus, pancreatic cancer in contact with the superior mesenteric vein/portal vein may be considered as borderline resectable pancreatic cancer.

Variaciones anatómicas en la vascularización del colon derecho y su implicancia en la escisión completa del mesocolon con linfadenectomía D3. Estudio de corte transversal / Anatomical variations in right colon vascularization: its implication in complete mesocolic excision with D3 lymphadenectomy. A cross-sectional study

Introducción: La escisión completa del mesocolon con linfadenectomía D3 (CME-D3) mejora los resultados de los pacientes operados por cáncer del colon. Reconocer adecuadamente la anatomía vascular es fundamental para evitar complicaciones. Objetivo: El objetivo primario fue determinar la prevalencia de las variaciones anatómicas de la arteria mesentérica superior (AMS) y sus ramas en relación a la vena mesentérica superior (VMS). El objetivo secundario fue evaluar la asociación entre las distintas variantes anatómicas y el sexo y la etnia de lo pacientes. Diseño: Estudio de corte transversal. Material y métodos: Se incluyeron 225 pacientes con cáncer del colon derecho diagnosticados entre enero 2017 y diciembre de 2020. Dos radiólogos independientes describieron la anatomía vascular observada en las tomografías computadas. Según la relación de las ramas de la AMS con la VMS, la población fue dividida en 2 grupos y subdividida en 6 (1a-c, 2a-c). Resultados: La arteria ileocólica fue constante, transcurriendo en el 58,7% de los casos por la cara posterior de la VMS. La arteria cólica derecha, presente en el 39,6% de los pacientes, cruzó la VMS por su cara anterior en el 95,5% de los casos. La variante de subgrupo más frecuente fue la 2a seguida por la 1a (36,4 y 24%, respectivamente). No se encontró asociación entre las variantes anatómicas y el sexo u origen étnico. Conclusión: Las variaciones anatómicas de la AMS y sus ramas son frecuentes y no presentan un patrón predominante. No hubo asociación entre las mismas y el sexo u origen étnico en nuestra cohorte. El reconocimiento preoperatorio de estas variantes mediante angiotomografía resulta útil para evitar lesiones vasculares durante la CME-D3. (AU)

Background: Complete mesocolic excision with D3 lymphadenectomy (CME-D3) improves the outcomes of patients operated on for colon cancer. Proper recognition of vascular anatomy is essential to avoid complications. Aim: Primary outcome was to determine the prevalence of anatomical variations of the superior mesenteric artery (SMA) and its branches in relation to the superior mesenteric vein (SMV). Secondary outcome was to evaluate the association between these anatomical variations and sex and ethnicity of the patients. Design: Cross-sectional study. Material and methods: Two hundred twenty-fivepatients with right colon cancer diagnosed between January 2017 and December 2020 were included. Two independent radiologists described the vascular anatomy of computed tomography scans. The population was divided into 2 groups and subdivided into 6 groups (1a-c, 2a-c), according to the relationship of the SMA and its branches with the SMV. Results: The ileocolic artery was constant, crossing the SMV posteriorly in 58.7% of the cases. The right colic artery, present in 39.6% of the patients, crossed the SMV on its anterior aspect in 95.5% of the cases. The most frequent subgroup variant was 2a followed by 1a (36.4 and 24%, respectively). No association was found between anatomical variants and gender or ethnic origin. Conclusions: The anatomical variations of the SMA and its branches are common, with no predominant pattern. There was no association between anatomical variations and gender or ethnic origin in our cohort. Preoperative evaluation of these variations by computed tomography angi-ography is useful to avoid vascular injuries during CME-D3. (AU)

Portal Vein or Superior Mesenteric Vein Thrombosis with Dose-Escalated Radiation for Borderline or Locally Advanced Pancreatic Cancer.

PURPOSE: Portal vein and superior mesenteric vein thrombosis (PVT/SMVT) are potentially morbid complications of radiation dose-escalated local therapy for pancreatic cancer. We retrospectively reviewed records for patients treated with and without intraoperative radiation (IORT) to identify risk factors for PVT/SMVT. METHODS: Ninety-six patients with locally advanced or borderline resectable pancreatic adenocarcinoma received neoadjuvant therapy followed by surgical exploration from 2009 to 2014. Patients at risk for close or positive surgical margins received IORT boost to a biologically effective dose (BED10) > 100. Prognostic factors for PVT/SMVT were evaluated using competing risks regression. RESULTS: Median follow-up was 79 months for surviving patients. Fifty-six patients (58%) received IORT. Twenty-nine patients (30%) developed PVT/SMVT at a median time of 18 months. On univariate competing risks regression, operative blood loss and venous repair with a vascular interposition graft, but not IORT dose escalation or diabetes history, were significantly associated with PVT/SMVT. The development of thrombosis in the absence of recurrence was significantly associated with a longstanding diabetes history, post-neoadjuvant treatment CA19-9, and operative blood loss. All 4 patients who underwent both IORT and vascular repair with a graft developed PVT/SMVT. PVT/SMVT in the absence of recurrence is not associated with significantly worsened overall survival but led to frequent medical interventions. CONCLUSIONS: Approximately 30% of patients who underwent neoadjuvant chemoradiation for PDAC developed PVT/SMVT a median of 18 months following surgery. This was significantly associated with venous reconstruction with vascular grafts, but not with escalating radiation dose. PVT/SMVT in the absence of recurrence was associated with significant morbidity.