Pancreatectomy with En Bloc Superior Mesenteric Vein and All Its Tributaries Resection without PV/SMV Reconstruction for "Low" Locally Advanced Pancreatic Head Cancer.

The "vein definition" for locally advanced pancreatic ductal adenocarcinoma (LA PDAC) assumes portal-to-superior mesenteric vein (PV/SMV) unreconstructability due to tumor involvement or occlusion. Radical pancreatectomies with SMV resection without PV/SMV reconstruction are scarcely discussed in the literature. Retrospective analysis of 19 radical pancreatectomies for "low" LA PDAC with SMV and all its tributaries resection without PV/SMV reconstruction has shown zero mortality; overall morbidity-56%; Dindo-Clavien-3-10.5%; R0-rate-82%; mean operative procedure time-355 ± 154 min; mean blood loss-330 ± 170 mL; delayed gastric emptying-25%; and clinically relevant postoperative pancreatic fistula-8%. In three cases, surgery was associated with superior mesenteric (n2) and common hepatic artery (n1) resection. Surgery was completed without vein reconstruction (n13) and with inferior mesenteric-to-splenic anastomosis (n6). There were no cases of liver, gastric, or intestinal ischemia. A specific complication of the SMV resection without reconstruction was 2-3 days-long intestinal edema (48%). Median overall survival was 25 months, and median progression-free survival was 18 months. All the relapses, except two, were distant. The possibility of successful SMV resection without PV/SMV reconstruction can be predicted before surgery by CT-based reconstructions. The mandatory anatomical conditions for the procedure were as follows: (1) preserved SMV-SV confluence; (2) occluded SMV for any reason (tumor or thrombus); (3) well-developed inferior mesenteric vein collaterals with dilated intestinal veins; (4) no right-sided vein collaterals; and (5) no varices in the upper abdomen. Conclusion: "Low" LA PDACs involving SMV with all its tributaries can be radically and safely resected in highly and specifically selected cases without PV/SMV reconstruction with an acceptable survival rate.

Endovascular Stenting for Idiopathic Stenosis of the Superior Mesenteric Vein: A Case Report.

Idiopathic superior mesenteric vein (SMV) stenosis, where no clear causative factor is identifiable, remains a clinical rarity. We present a detailed case report of a patient with idiopathic stenosis of the SMV who underwent successful endovascular stenting. This report outlines the patient's clinical presentation, diagnostic imaging findings, procedural approach by the interventional radiology team, and subsequent management. Endovascular stenting is a viable therapeutic option for patients with idiopathic SMV stenosis. This case demonstrates that with appropriate interventional and post-procedural management, long-term stent patency and thrombosis prevention can be achieved. The success of this case encourages further investigation into endovascular treatments for venous stenoses.

Multidetector computer tomography and magnetic resonance imaging of double superior mesenteric veins: A case report.

BACKGROUND: This study aimed to describe the findings of double superior mesenteric veins (SMVs), a rare anatomical variation, on multidetector computer tomography (MDCT) and magnetic resonance imaging (MRI) images. CASE SUMMARY: We describe the case of a 34-year-old male, who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis. MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein (SMV), the double SMVs. CONCLUSION: The double SMVs are a congenital abnormality without potential clinical manifestation. Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury.

Case report: Rapid development of acute symptomatic portal vein system thrombosis after endoscopic variceal therapy in a patient with liver cirrhosis.

Acute portal vein thrombosis (PVST), a serious complication of liver cirrhosis, is characterized as abdominal pain secondary to intestinal ischemia, and even intestinal necrosis. Anticoagulation is recommended for the treatment of acute PVST, but is often postponed in cirrhotic patients with acute variceal bleeding or those at a high risk of variceal bleeding. Herein, we reported a 63-year-old male with a 14-year history of alcoholic liver cirrhosis who developed progressive abdominal pain related to acute portal vein and superior mesenteric vein thrombosis immediately after endoscopic variceal ligation combined with endoscopic cyanoacrylate glue injection for acute variceal bleeding. Fortunately, acute PVST was successfully recanalized by the use of low molecular weight heparin. Collectively, this case suggests that acute symptomatic PVST can be secondary to endoscopic variceal therapy in liver cirrhosis, and can be safely and successfully treated by anticoagulation.

Successful Multimodal Treatment of Pancreatic Cancer With Extensive Superior Mesenteric Vein Thrombosis Utilizing Chemotherapy Combined With Direct Oral Anticoagulant.

It is well known that portal vein thrombosis (PVT) sometimes occurs in pancreatic cancer (PC). However, no effective treatment plan for PVT in PC patients has yet been proposed. We experienced a successfully treated case of borderline resectable pancreatic cancer (PC-BR) with extensive superior mesenteric vein thrombosis utilizing intensive chemotherapy combined with direct oral anticoagulant. The thrombus disappeared and the tumor shrank, enabling curative surgery, and long-term survival for more than five years has been achieved. We report this successful case that we experienced as an option for the treatment of PC-BR with PVT in the future era when multimodal treatment is important.

The risk of developing splanchnic vein thrombosis in acute pancreatitis increases 3 days after symptom onset: A systematic review and meta-analysis.

BACKGROUND: Splanchnic vein thrombosis is a complication of acute pancreatitis (AP) and is likely often underdiagnosed. OBJECTIVES: We aimed to understand the time course and risk factors of splanchnic vein thrombosis in the early phase of AP. METHODS: A systematic search was conducted using the PRISMA guidelines (PROSPERO registration CRD42022367578). Inclusion criteria were appropriate imaging techniques in adult AP patients, studies that reported splanchnic vein thrombosis data from the early phase, and reliable information on the timing of imaging in relation to the onset of pancreatitis symptoms or hospital admission. The proportion of patients with thrombosis with 95% confidence intervals (CI) was calculated using random-effects meta-analyses, and multiple subgroup analyses were performed. RESULTS: Data from 1951 patients from 14 studies were analyzed. The proportion of patients with splanchnic vein thrombosis within 12 days after symptom onset was 0.13 (CI 0.07-0.23). The occurrence was lowest at 0.06 (CI 0.03-0.1) between 0 and 3 days after symptom onset, and increased fourfold to 0.23 (CI 0.16-0.31) between 3 and 11 days. On hospital admission, the proportion of patients affected was 0.12 (CI 0.02-0.49); it was 0.17 (CI 0.03-0.58) 1-5 days after admission. The prevalence in mild, moderate, and severe AP was 0.15 (CI 0.05-0.36), 0.26 (CI 0.15-0.43), and 0.27 (CI 0.17-0.4), respectively. Alcoholic etiology (0.31, CI 0.13-0.58) and pancreatic necrosis (0.55, CI 0.29-0.78, necrosis above 30%) correlated with increased SVT prevalence. CONCLUSION: The risk of developing splanchnic vein thrombosis is significant in the early stages of AP and may affect up to a quarter of patients. Alcoholic etiology, pancreatic necrosis, and severity may increase the prevalence of splanchnic vein thrombosis.

miR-138-5p ameliorates intestinal barrier disruption caused by acute superior mesenteric vein thrombosis injury by inhibiting the NLRP3/HMGB1 axis.

Background: Acute superior mesenteric venous thrombosis (ASMVT) decreases junction-associated protein expression and intestinal epithelial cell numbers, leading to intestinal epithelial barrier disruption. Pyroptosis has also recently been found to be one of the important causes of mucosal barrier defects. However, the role and mechanism of pyroptosis in ASMVT are not fully understood. Methods: Differentially expressed microRNAs (miRNAs) in the intestinal tissues of ASMVT mice were detected by transcriptome sequencing (RNA-Seq). Gene expression levels were determined by RNA extraction and reverse transcription-quantitative PCR (RT-qPCR). Western blot and immunofluorescence staining analysis were used to analyze protein expression. H&E staining was used to observe the intestinal tissue structure. Cell Counting Kit-8 (CCK-8) and fluorescein isothiocyanate/propidine iodide (FITC/PI) were used to detect cell viability and apoptosis, respectively. Dual-luciferase reporter assays prove that miR-138-5p targets NLRP3. Results: miR-138-5p expression was downregulated in ASMVT-induced intestinal tissues. Inhibition of miR-138-5p promoted NLRP3-related pyroptosis and destroyed tight junctions between IEC-6 cells, ameliorating ASMVT injury. miR-138-5p targeted to downregulate NLRP3. Knockdown of NLRP3 reversed the inhibition of proliferation, apoptosis, and pyroptosis and the decrease in tight junction proteins caused by suppression of miR-138-5p; however, this effect was later inhibited by overexpressing HMGB1. miR-138-5p inhibited pyroptosis, promoted intestinal epithelial tight junctions and alleviated ASMVT injury-induced intestinal barrier disruption via the NLRP3/HMGB1 axis.

Rare deep vein thrombosis in pregnancy and puerperium 3 case series; upper extremities vein thrombosis, ovarian vein thrombosis, portal and superior mesenteric vein thrombosis.

Pregnancy induces a hypercoagulable state, elevating thrombosis risk by 5-6 times compared to non-pregnant conditions. Predominantly affecting the left lower extremity due to anatomical and hematological factors, deep vein thrombosis can escalate into pulmonary embolism, impacting mortality. The authors aim to report rare incidents of thrombosis beyond the norm, including upper extremity vein thrombosis, right ovarian vein thrombosis, and portal vein and superior mesenteric vein thrombosis, highlighting their significance. Obstetricians should be mindful that thrombosis can occur not only in the lower extremities but also in other areas. Especially when symptoms such as fever unresponsive to antibiotics, atypical pain, and an abnormally high C-reactive protein level are present. Considering the possibility of a rare thrombosis is crucial. Understanding these less common thrombotic events during pregnancy and the postpartum period can contribute to the improvement of timely diagnosis and management strategies.

Multiple Thrombotic, Infectious, and Cardiopulmonary Complications Following Laparoscopic Converted to Open Colectomy Procedure: A Case Report and Literature Review.

All surgeries, from minor procedures, such as sutures, to major surgeries, such as open abdominal surgery, carry with them risk for complications. Among the most frequently encountered complications are surgical site infections and thrombotic complications. Less frequently, cardiac complications such as atrial fibrillation are seen. In this case report, we discuss the various complications encountered during the hospital stay of a 61-year-old male following a laparoscopic converted to open colectomy procedure for the treatment of a colorectal mass. Following surgery, a surgical pathology report revealed a newly diagnosed stage 3b colorectal adenocarcinoma. Multiple abscesses in the abdominopelvic cavity were discovered on computed tomography (CT), revealing a major surgical site infectious process. These findings warranted emergent surgical intervention and placement of multiple Jackson-Pratt drains. Due to previously untreated carcinoma promoting a prothrombotic state, the patient developed numerous thrombotic complications such as segmental pulmonary embolism, superior mesenteric vein thrombosis, and superficial thrombophlebitis of the saphenous veins. He also developed new-onset paroxysmal atrial fibrillation secondary to postoperative pain, as well as bilateral pleural effusions. Here, we shed light on the mechanisms of development of such complications, as well as the management and methods for prevention.

Case Report: PROS1 (p.Leu584Arg) pathogenic mutation causes portal and superior mesenteric venous thromboembolism.

Background: Genetic and acquired risk factors are fundamental to developing venous thromboembolism. Autosomal dominant protein S deficiency caused by pathogenic mutations in the PROS1 gene is a well-known risk factor for thrombophilia. Case presentation: We report a 30-year-old male patient who presented to the hospital with portal vein thrombosis. The patient had a history of abdominal pain for one month. Abdominal vascular CT showed venous thrombosis in the portal vein and superior mesenteric vein. He was diagnosed with "portal and superior mesenteric vein thrombosis, small bowel obstruction and necrosis, acute upper gastrointestinal bleeding (UGIB), hemorrhagic shock." Serum protein S levels were decreased, and gene sequencing revealed a heterozygous missense mutation in PROS1, c.1571T > G (p.Leu584Arg). The patient received anticoagulation therapy with Enoxaparin Sodium and rivaroxaban, transjugular intrahepatic portosystemic shunt (TIPS), and ICU treatments. Although the patient had a severe bleeding event during anticoagulation therapy, he recovered well after active treatment and dynamic monitoring of anti-Xa. Conclusion: Hereditary protein S deficiency caused by a mutation in the PROS1 gene is the genetic basis of this patient, and Enoxaparin Sodium and rivaroxaban have been shown to be highly effective.

Superior Mesenteric Vein Dilatation With Ladd's Band Causing Partial Intestinal Obstruction in a Five-Year-Old Male Child: A Case Report.

Midgut malrotation has a noticeable frequency among congenital anomalies and presents mostly as vomiting. We report a case of a five-year-old boy with recurrent attacks of bilious vomiting and mild epigastric colicky abdominal pain for a year. Midgut malrotation with Ladd's band and superior mesenteric vein (SMV) dilatation causing partial intestinal obstruction were diagnosed based on the clinical presentation, upper gastrointestinal (GI) barium follow-through study, computed tomography (CT) scan with and without IV contrast, and intraoperative findings. In the upper GI barium study, the duodenum was passing anteriorly, and the second and proximal third portions were persistently dilated with recurring to-and-fro type peristalsis, resulting in delayed passage through the third portion. In the abdomen and pelvis CT scan with and without IV contrast, the SMV was dilated, forming a venous collar around the third portion of the duodenum and causing partial obstruction. Exploratory laparotomy revealed a hugely dilated SMV trapped in the Ladd's band. Ladd's procedure was done besides releasing the SMV and widening the root of the mesentery. The postoperative follow-up was smooth, without any relapse of the previous symptoms. Midgut malrotation in the older age group is rare in itself because there are relatively few cases documented in this age range. We determined to present this case to raise awareness of knowledge concerning the diagnosis and timely management of this condition in order to prevent comorbidity. In addition, we realise that SMV dilatation is an uncommon correlation of the known condition, midgut malrotation, and hope to contribute to the literature.

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.

A Case of Loss of Consciousness Due to Thrombosis of the Inferior Vena Cava and Portal Vein.

We present a case where intraperitoneal venous thrombosis was difficult to treat. It is difficult to suspect intraperitoneal venous thrombosis in patients who have visited the hospital due to loss of consciousness, and it is necessary to administer anticoagulants early for treatment and to determine the appropriate timing for surgical intervention. The patient was a 78-year-old male who independently performed his daily activities. On the day of admission, he lost consciousness and was brought to our hospital. Computed tomography (CT) angiography revealed thrombi from the inferior vena cava and portal vein to the superior mesenteric vein, and the patient was started on anticoagulant therapy. The CT angiography images on day 7 of the illness revealed that the thrombus in the superior mesenteric vein expanded to the caudal side. Intestinal necrosis occurred on day 22 of the illness, and emergency laparotomy was performed. The chosen course of treatment was successful, and the patient was discharged on the 48th day.

Superior Mesenteric Vein Aneurysm With Arteriovenous Communication and Portal Vein Thrombosis: A Rare Presentation in Non-cirrhotic Portal Hypertension.

Visceral venous aneurysms are exceedingly rare clinical entities reported in the literature. Venous aneurysms are usually acquired in origin, with most often portal hypertension as the underlying pathology. Most venous aneurysms are incidental findings on imaging. Complications of venous aneurysms like rupture with catastrophic outcomes had been reported. However, no clear guidelines exist regarding the management of portal venous aneurysms as most of the data is available only from case reports. Here, we report a rare finding of fusiform superior mesenteric vein (SMV) aneurysm with arteriovenous communication and portal vein thrombosis in the background of non-cirrhotic portal hypertension.

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.

A rare complication with superior mesenteric vein thrombosis after laparoscopic sleeve gastrectomy: A case report.

Laparoscopic sleeve gastrectomy (LSG) has become a frequent procedure to reduce weight and morbid obesity. The procedure involves laparoscopic resection of more than 75% of the greater curvature of the stomach, resulting in early satiety and neuro-hormonal changes that collectively promote effective weight loss. We present a rare case of complication of superior mesenteric vein thrombosis (SMVT) and splenic vein after LSG, with consequent bowel ischemia that was treated with open laparotomy and appropriate anticoagulation therapy. A 56-year-old obese woman (BMI of 42.5 kg/m2), smoker for 30 years, presented to the emergency department with symptoms such as abdominal pain, fever, nausea and vomiting, 2 weeks after LSG intervention. Her white blood cell count was 15.5 (normal values: 3.8-10.4 × 103 /µL), while C- reactive protein level was 193 (normal values: 0.0-6.0 mg/L) and her D-Dimer level 4.69 (normal values: 0-0.50 mg/L). Abdominal CT with contrast showed a filling defect in the superior mesenteric and splenic vein, free perihepatic and Douglas pouch fluid, as well as small bowel thickening. An open laparotomy was performed and the necrotic segment of bowel of 80 cm was removed. The postoperative period went relatively well, despite the diarrhea that continued for the next 4 months after the intervention. The most common causes leading the development of this complication include: hypercoagulable state, dehydration, increased intra-abdominal pressure during the procedure and other secondary factors. The main symptom is abdominal pain, followed by nausea, vomiting, diarrhea and bleeding from the gastrointestinal tract. SMVT and SVT should be considered as a possible complication in patients with abdominal pain and increased inflammatory parameters after LSG. Early diagnosis through CT imaging and rapid anticoagulation therapy is considered to reduce further complications such as intestinal infarction and portal hypertension.

Variations of the double superior mesenteric vein are not rare: An observational study using computed tomography, three-dimensional image reconstruction, and surgery.

INTRODUCTION: Few studies have evaluated variations of the main trunk of the superior mesenteric vessels. Particularly, the double superior mesenteric vein (DSMV) has not been described in detail. This study aimed to establish the definition, anatomical characteristics, and underlying clinical significance of the DSMV. MATERIALS AND METHODS: A total of 115 patients with colorectal cancer were included in this retrospective study between March 2020 and March 2022. The anatomical characteristics were analyzed using computed tomography, three-dimensional image reconstructions, and surgical videos. RESULTS: Among the patients enrolled, 22 (19.1%) had DSMVs. The median diameters of the right and left superior mesenteric veins were similar. The superior mesenteric artery was sandwiched between the right and the left superior mesenteric veins. The left superior mesenteric vein mainly crossed the ventral side of the superior mesenteric artery (63.6%). In 1 case, the right superior mesenteric vein was mistakenly resected intraoperatively. The DSMV was classified into types I and II based on whether the right and left trunks formed a common trunk; it was further classified into subtypes a and b based on the colonic vein confluence. The proportions of type I-a, I-b, II-a, and II-b were 4.5%, 27.3%, 9.1%, and 59.1%, respectively. The middle colic veins drained into the left superior mesenteric vein in 19 cases (86.4%). CONCLUSIONS: The DSMV is more common than previously thought. For the first time, the definition and four types of the DSMV were proposed. The presence of a DSMV should be considered during right hemicolectomies.

Acute Portal Vein Thrombosis as an Initial Presentation of Protein C Deficiency: A Case Report.

Protein C (PC) is an essential vitamin K-dependent protein that regulates thrombosis and hemostasis in the body. A mutation in the PROC gene on chromosome 2q14.3 results in PC deficiency. The clinical presentation of PC deficiency can vary, ranging from a single vein thrombosis to disseminated intravascular coagulation, purpura fulminans, or even life-threatening complications such as sepsis. Here, we present a case of a 37-year-old female who was found to have acute portal vein thrombosis as an initial presentation of PC deficiency. She presented to the hospital with acute onset of abdominal pain associated with nausea, blood-streaked emesis, and bloody bowel movement.

Pediatric hypereosinophilic syndrome associated with liver damage, portal vein, splenic vein and superior mesenteric vein thromboses: a case report.

BACKGROUND: The hypereosinophilic syndrome (HES) is a group of rare blood disorders characterized by persistent eosinophilia and damage to multiple organs. HES can be either primary, secondary or idiopathic. Secondary HES are commonly caused by parasitic infections, allergic reactions or cancer. We described a pediatric case of HES associated with liver damage and multiple thrombi. A 12-year-old boy with eosinophilia was complicated with severe thrombocytopenia, liver damage, portal vein, splenic vein, and superior mesenteric vein thromboses. The thrombi recanalized after treatment with methylprednisolone succinate and low molecular weight heparin. No side effects appeared after 1-month. CONCLUSIONS: Corticosteroids should be used at an early stage of HES to prevent further damage to vital organs. Anticoagulants should be recommended only in cases with thrombosis which should be actively screened as a part of evaluation of end organ damage.

Ligamentum teres hepatis as a graft for portal and/or superior mesenteric vein reconstruction: From bench to bedside.

BACKGROUND: Pancreaticoduodenectomy combined with portal vein (PV) and/or superior mesenteric vein (SMV) resection in patients with pancreaticobiliary malignancy has become a common surgical procedure. There are various grafts currently used for PV and/or SMV reconstruction, but each of these grafts have certain limitations. Therefore, it is necessary to explore novel grafts that have an extensive resource pool, are low cost with good clinical application, and are without immune response rejection or additional damage to patients. AIM: To observe the anatomical and histological characteristics of the ligamentum teres hepatis (LTH) and evaluate PV/SMV reconstruction using an autologous LTH graft in pancreaticobiliary malignancy patients. METHODS: In 107 patients, the post-dilated length and diameter in resected LTH specimens were measured. The general structure of the LTH specimens was observed by hematoxylin and eosin (HE) staining. Collagen fibers (CFs), elastic fibers (EFs), and smooth muscle (SM) were visualized by Verhoeff-Van Gieson staining, and the expression of CD34, factor VIII-related antigen (FVIIIAg), endothelial nitric oxide synthase (eNOS), and tissue type plasminogen activator (t-PA) were detected using immunohistochemistry in LTH and PV (control) endothelial cells. PV and/or SMV reconstruction using the autologous LTH was conducted in 26 patients with pancreaticobiliary malignancies, and the outcomes were retrospectively analyzed. RESULTS: The post-dilated length of LTH was 9.67 ± 1.43 cm, and the diameter at a pressure of 30 cm H2O was 12.82 ± 1.32 mm at the cranial end and 7.06 ± 1.88 mm at the caudal end. Residual cavities with smooth tunica intima covered by endothelial cells were found in HE-stained LTH specimens. The relative amounts of EFs, CFs and SM in the LTH were similar to those in the PV [EF (%): 11.23 ± 3.40 vs 11.57 ± 2.80, P = 0.62; CF (%): 33.51 ± 7.71 vs 32.11 ± 4.82, P = 0.33; SM (%): 15.61 ± 5.26 vs 16.74 ± 4.83, P = 0.32]. CD34, FVIIIAg, eNOS, and t-PA were expressed in both LTH and PV endothelial cells. The PV and/or SMV reconstructions were successfully completed in all patients. The overall morbidity and mortality rates were 38.46% and 7.69%, respectively. There were no graft-related complications. The postoperative vein stenosis rates at 2 wk, 1 mo, 3 mo and 1 year were 7.69%, 11.54%, 15.38% and 19.23%, respectively. In all 5 patients affected, the degree of vascular stenosis was less than half of the reconstructed vein lumen diameter (mild stenosis), and the vessels remained patent. CONCLUSION: The anatomical and histological characteristics of LTH were similar to the PV and SMV. As such, the LTH can be used as an autologous graft for PV and/or SMV reconstruction in pancreaticobiliary malignancy patients who require PV and/or SMV resection.