A retrospective multicentre clinical study on management of isolated splenic vein thrombosis: risks and benefits of anticoagulation.

INTRODUCTION: Isolated splenic vein thrombosis (iSVT) is a common complication of pancreatic disease. Whilst patients remain asymptomatic, there is a risk of sinistral portal hypertension and subsequent bleeding from gastric varices if recanalisation does not occur. There is wide variation of iSVT treatment, even within single centres. We report outcomes of iSVT from tertiary referral hepatobiliary and pancreatic (HPB) units including the impact of anticoagulation on recanalisation rates and subsequent variceal bleeding risk. METHODS: A retrospective cohort study including all patients diagnosed with iSVT on contrast-enhanced CT scan abdomen and pelvis between 2011 and 2019 from two institutions. Patients with both SVT and portal vein thrombosis at diagnosis and isolated splenic vein thrombosis secondary to malignancy were excluded. The outcomes of anticoagulation, recanalisation rates, risk of bleeding and progression to portal vein thrombosis were examined using CT scan abdomen and pelvis with contrast. RESULTS: Ninety-eight patients with iSVT were included, of which 39 patients received anticoagulation (40%). The most common cause of iSVT was acute pancreatitis n = 88 (90%). The recanalisation rate in the anticoagulation group was 46% vs 15% in patients receiving no anticoagulation (p = 0.0008, OR = 4.7, 95% CI 1.775 to 11.72). Upper abdominal vascular collaterals (demonstrated on CT scan angiography) were significantly less amongst patients who received anticoagulation treatment (p = 0.03, OR = 0.4, 95% CI 0.1736 to 0.9288). The overall rate of upper GI variceal-related bleeding was 3% (n = 3/98) and it was independent of anticoagulation treatment. Two of the patients received therapeutic anticoagulation. CONCLUSION: The current data supports that therapeutic anticoagulation is associated with a statistically significant increase in recanalisation rates of the splenic vein, with a subsequent reduction in radiological left-sided portal hypertension. However, all patients had a very low risk of variceal bleeding regardless of anticoagulation. The findings from this retrospective study should merit further investigation in large-scale randomised clinical trials.

Long-term outcomes after spleen-preserving distal pancreatectomy with splenic vessels preservation or resection: A nationwide survey of the Japanese Society of Pancreatic Surgery.

BACKGROUND: Spleen preserving distal pancreatectomy is achieved by either splenic vessel resection or splenic vessel preservation. However, the long-term outcomes of spleen-preserving distal pancreatectomy with splenic vessel resection and spleen-preserving distal pancreatectomy with splenic vessel preservation are not well known. This study aimed to evaluate the long-term outcomes of spleen-preserving distal pancreatectomy with splenic vessel resection and spleen-preserving distal pancreatectomy with splenic vessel preservation. METHODS: The study included a total of 335 patients who underwent spleen-preserving distal pancreatectomy during the study period and underwent computed tomography or magnetic resonance imaging 3 and 5 years after surgery in the Japan Society of Pancreatic Surgery member institutions. We evaluated the diameter of the perigastric and gastric submucosal veins, patency of the splenic vessels, and splenic infarction. Preoperative backgrounds and short- and long-term outcomes were compared between the 2 groups. RESULTS: Forty-four (13.1%) and 291 (86.9%) patients underwent spleen-preserving distal pancreatectomy with splenic vessel resection and spleen-preserving distal pancreatectomy with splenic vessel preservation, respectively. There were no significant differences in short-term outcomes between the 2 groups. Regarding long-term outcomes, the prevalence of perigastric varices was higher (P = .006), and platelet count was lower (P = .037) in the spleen-preserving distal pancreatectomy with splenic vessel resection group. However, other complications, such as gastric submucosal varices, postoperative splenic infarction, gastrointestinal bleeding, reoperation, postoperative splenectomy, and other hematologic parameters, were not significantly different between the 2 groups 5 years after surgery. In terms of the patency of splenic vessels in spleen preserving distal pancreatectomy with splenic vessel preservation cases, partial or complete occlusion of the splenic artery and vein was observed 5 years after surgery in 19 (6.5%) and 55 (18.9%) patients, respectively. CONCLUSION: Perigastric varices and thrombocytopenia were observed more in spleen-preserving distal pancreatectomy with splenic vessel resection, yet late clinical events such as gastrointestinal bleeding and splenic infarction are acceptable for spleen-preserving distal pancreatectomy with splenic vessel preservation.

Impact of radiological and pathological splenic vein involvement in patients with resectable pancreatic body or tail cancer.

PURPOSE: Several studies have reported a negative impact on survival associated with splenic vessel involvement, especially splenic artery (SpA) involvement, in patients diagnosed with pancreatic body or tail cancer. However, there is limited research on splenic vein (SpV) involvement. Therefore, we aimed to elucidate the significance of splenic vessel involvement, especially SpV involvement, in patients with resectable pancreatic body or tail cancer. METHODS: Between January 2007 and December 2021, 116 consecutive patients underwent distal pancreatectomies for pancreatic body or tail cancer. Among them, this study specifically examined 88 patients with resectable pancreatic body or tail cancer to elucidate prognostic factors using a multivariable Cox proportional analysis. The Kaplan-Meier method evaluated the impact of SpV involvement in terms of both radiological and pathological aspects and the efficacy of neoadjuvant therapy. RESULTS: Higher pre-operative carcinoembryonic antigen levels, larger tumour size, pathological SpV invasion, and non-completion of adjuvant therapy were identified as independent poor prognostic factors for overall survival (OS) and recurrence-free survival (RFS). Additionally, patients with radiological SpV encasement had significantly worse prognoses in terms of OS (p = 0.039) and RFS (p < 0.001). The sensitivity and specificity of multidetector-row computed tomography for detecting pathological SpV invasion were 81.0% and 61.2%, respectively. However, the prognostic impact of neoadjuvant therapy could not be determined, regardless of radiological SpV involvement. CONCLUSION: Radiological and pathological SpV involvement is a poor prognostic factor for patients with resectable pancreatic body or tail cancer. New innovative treatments and effective neoadjuvant therapy regimens are required for patients with SpV involvement.

Splenic vein tumor thrombosis is a major prognostic factor in distal pancreatic adenocarcinoma.

BACKGROUND: The prognostic value of splenic vessel involvement in distal pancreatic adenocarcinoma remains controversial. The aim of the study was to assess its prognostic relevance in a large multicenter cohort. METHODS: Patients who underwent pancreatosplenectomy for distal pancreatic adenocarcinoma were identified from 5 pancreatic surgical centers. A pathology review of the surgical specimens was performed to assess splenic vessel involvement, defined as invasion of the vessel's adventitia or deeper, and confirm the presence of splenic vein tumor thrombosis. Prognostic factors associated with overall and relapse-free survival were evaluated. RESULTS: 149 patients underwent upfront surgery. Splenic vascular involvement was observed in 69 of them (46.3%). A parietal infiltration of the splenic artery or splenic vein was observed in 26 (17.5%) and 49 patients (32.8%), respectively. A pathologic tumor thrombosis of the splenic vein was identified in 22 patients (14.8%) and associated with larger tumors (>20 mm) (P = .023), more perineural (P = .017), and lymphovascular (P = .002) invasion, and more positive lymph node (P = .001). After a median follow-up of 50.8 months (95% confidence interval: 44.3-57.3), the cumulative 5-year overall and relapse-free survival were 46.2% and 33%, respectively. In multivariate analysis, in addition to lymph node metastasis (hazard ratio = 1.8; 95% confidence interval [1.1-3.1]; P = .023) and perineural invasion (hazard ratio = 3.5; 95% confidence interval [1.3-9.7]; P = .016), presence of splenic vein tumor thrombosis was the only splenic vascular involvement that affected independently the overall survival (HR = 2.3; 95% confidence interval [ 1.3-4.3]; P = .006). CONCLUSION: In resectable distal pancreatic adenocarcinoma, a pathologic tumor thrombosis of the splenic vein is an independent prognostic factor of overall survival. To define the perioperative oncological strategy, a preoperative evaluation of splenic vessel involvement and thrombosis is needed.

Laparoscopic spleen-preserving distal pancreatectomy: A novel technique with splenic artery resection and splenic vein preservation.

INTRODUCTION: Laparoscopic spleen-preserving distal pancreatectomy (LSDP) is widely performed to treat benign and low-grade malignant diseases. Although preservation of splenic vessels may be desirable considering the risk of postoperative complications, it is sometimes difficult due to tumor size, inflammation, and proximity of the tumor and splenic vessels. Herein, we present the first case of LSDP with splenic artery resection and splenic vein preservation. MATERIALS AND SURGICAL TECHNIQUE: A 40-year-old woman with a pancreatic tumor was referred to our hospital. Contrast-enhanced computed tomography (CT) revealed a tumor in the pancreatic tail that was in contact with the splenic artery and distant from the splenic vein. The splenic artery and vein were separated from the pancreas near the dissection line. The splenic artery was resected after pancreatic dissection using a linear stapler. After the pancreatic tail was separated from the splenic hilum while preserving the splenic vein, the distal side of the splenic artery was resected, and the specimen was removed. The postoperative course was uneventful and the patient was discharged on postoperative Day 9. Four months after surgery, postoperative follow-up CT findings showed neither splenic infarction nor gastric varices. DISCUSSION: This technique is an alternative method of splenic preservation when there is no attachment of the tumor to the splenic vein or uncontrolled expected bleeding of the splenic artery using the Kimura technique.

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.

Drainage pattern of the splenic flexure vein and its accompanying arteries using three-dimensional computed tomography angiography: a single-centre study of 600 patients.

AIM: The splenic flexure has variable vascular anatomy, and the details of the venous forms are not known. In this study, we report the flow pattern of the splenic flexure vein (SFV) and the positional relationship between the SFV and arteries such as the accessory middle colic artery (AMCA). METHODS: This was a single-centre study using preoperative enhanced CT colonography images of 600 colorectal surgery patients. CT images were reconstructed into 3D angiography. SFV was defined as a vein flowing centrally from the marginal vein of the splenic flexure visible on CT. AMCA was defined as the artery feeding the left side of the transverse colon, separate from the left branch of the middle colic artery. RESULTS: The SFV returned to the inferior mesenteric vein (IMV) in 494 cases (82.3%), the superior mesenteric vein in 51 cases (8.5%) and the splenic vein in seven cases (1.2%). The AMCA was present in 244 cases (40.7%). The AMCA branched from the superior mesenteric artery or its branches in 227 cases (93.0% of cases with existing AMCA). In the 552 cases in which the SFV returned to the IMV, superior mesenteric vein or splenic vein, the left colic artery was the most frequent artery accompanying the SFV (42.2%), followed by the AMCA (38.1%) and the left branch of the middle colic artery (14.3%). CONCLUSIONS: The most common flow pattern of the vein in the splenic flexure is from the SFV to IMV. The SFV is frequently accompanied by the left colic artery or AMCA.

Intra-abdominal Hemorrhage Due to Splenic Vein Aneurysm Rupture Caused by Invasive Aspergillosis during Treatment for Advanced Non-small-cell Lung Cancer.

A 71-year-old man was admitted for left-sided chest pain. He had a history of diabetes, treatment with epidermal growth factor receptor-tyrosine kinase inhibitor for advanced non-small-cell lung cancer, and corticosteroid treatment for underlying lung diseases. Chest computed tomography showed consolidations in the bilateral lower lobes, and Aspergillus fumigatus was detected by bronchoscopy. Invasive pulmonary aspergillosis was suspected, and antifungal therapy with voriconazole was initiated; however, the patient passed away suddenly. Autopsy revealed disseminated Aspergillus infection and intra-abdominal hemorrhage due to the rupture of a splenic vein aneurysm caused by Aspergillus necrotizing vasculitis, which was considered the cause of death.

A case of Vp4 hepatocellular carcinoma with tumor thrombosis extending into the confluence of the splenic/portal vein achieved a good prognosis with emergent hepatectomy and postoperative adjuvant therapy with lenvatinib.

In this report, we describe a case of highly advanced hepatocellular carcinoma with tumor thrombosis extending into the main portal vein of the pancreas that was successfully treated with adjuvant lenvatinib after right hepatic resection with thrombectomy. A 70-year-old woman was referred from the clinic because of elevated hepatobiliary enzymes. The patient was positive for the hepatitis B virus antigen at our hospital. The tumor markers were highly elevated with alpha-fetoprotein (14.5 U/mL) and protein induced by vitamin K absence (PIVKAII) (1545 ng/mL), suggesting hepatocellular carcinoma. Dynamic abdominal computed tomography showed an early enhanced tumor approximately 6 cm in size and portal vein tumor thrombosis filling the main portal vein, but not extending into the splenic or superior mesenteric vein (SMV). On magnetic resonance imaging 1 week after CT, portal vein tumor thrombosis had extended to the confluence of the splenic vein with the SMV, indicating rapid tumor growth. Thus, we performed emergent right hepatectomy with tumor thrombectomy. Postoperatively, we treated the patient with lenvatinib for a tumor reduction surgery. Fortunately, the patient was alive 2 years postoperatively without recurrence. This case report suggests that a favorable outcome may be achieved with multidisciplinary treatment including resection and postoperative treatment with lenvatinib.

ANATOMICAL VARIATIONS OF PORTAL VENOUS SYSTEM: IMPORTANCE IN SURGICAL CLINIC.

AIM: Knowledge of the portal system and its anatomical variations aids to prevent surgical adverse events. The portal vein is usually made by the confluence of the superior mesenteric and splenic veins, together with their main tributaries, the inferior mesenteric, left gastric, and pancreaticoduodenal veins; however, anatomical variations are frequent. This article presents a literature review regarding previously described anatomical variations of the portal venous system and their frequency. METHODS: A systematic review of primary studies was performed in the databases PubMed, SciELO, BIREME, LILACS, Embase, ScienceDirect, and Scopus. Databases were searched for the following key terms: Anatomy, Portal vein, Mesenteric vein, Formation, Variation, Variant anatomic, Splenomesenteric vein, Splenic vein tributaries, and Confluence. RESULTS: We identified 12 variants of the portal venous bed, representing different unions of the splenic vein, superior mesenteric vein, and inferior mesenteric vein. Thomson classification of the end of 19th century refers to the three most frequent variants, with type I as predominant (M=47%), followed by type III (M=27.8%) and type II (M=18.6%). CONCLUSION: Thomson classification of variants is the most well-known, accounting for over 90% of portal venous variant found in clinical practice, inasmuch as the sum of the three junctions are found in over 93% of the patients. Even though rarer and accounting for less than 7% of variants, the other nine reported variations will occasionally be found during many abdominal operations.

Usefulness of partial splenic embolization for left-sided portal hypertension in a patient with a pancreatic neuroendocrine neoplasm: a case report and review of the literature.

Left-side portal hypertension (LSPH) is caused by isolated obstruction of the splenic vein and is associated with esophagogastric varices that extend from the lower esophagus to the greater curvature of the gastric body. Here, we report on a 74-year-old man with a pancreatic neuroendocrine neoplasm (NEN) in the pancreatic tail with multiple liver metastases. We decided that partial splenic embolization (PSE) was the best course of treatment to prevent rupture of the gastric varices, which were classified as markedly enlarged, nodular, or tumor-shaped and showed erosion of the mucosa. After PSE, the patient had no major complications and was discharged. At 3 and 6 months after the procedure, esophagogastroduodenoscopy and enhanced computerized tomography showed that the gastric varices had improved. This case demonstrates the usefulness of PSE for LSPH in patients with unresected pancreatic NEN.

Coincidence of splenic vein aneurysm and haemorrhagic cyst of the pancreas.

Pseudoaneurysm of the splenic vein is a rare entity which is associated with pancreatitis in 52 % cases. Pseudocysts of the pancreas create approximately 70 % of all cystic lesions of the pancreas. One of the most dangerous complications of pancreatic pseudocysts is bleeding into the cystic lumen. This is caused by perforation of the pseudoaneurysm of the splenic vein. Enzymatic damage of the splenic vein´s wall is the cause of pseudoaneurysm. The clinical condition varies. It can be asymptomatic or bring about haemodynamic instability. The diagnostic process of pseudoaneurysm of the splenic vein is difficult. This case study introduces a case of a 50­year­old man with the anamnesis of recurrent pancreatitis caused by alcoholism. He had abdominal pain and was diagnosed with a pseudocyst of the pancreas. Abdominal CT showed an extensive capsulated collection in the left subphrenic space, 23cm in diameter, with serosanguineous content and coagulations. The CT visualised the mass effect on the surrounding tissues and a complete deformation of the spleen. Between the collection and partially oppressed tail of the pancreas there was a venous pseudoaneurysm, 3.5cm in diameter. Considering its localization, it most probably originated from the splenic vein. Surgery was done. We did distal resection of the pancreas with a complete removal of the pseudocyst and spleen (Fig. 7, Ref. 11). Keywords: splenic vein, pseudoaneurysm, pancreatitis, pancreatic pseudocysts.

Splenic Arteriovenous Fistula Accompanied by Splenic Artery Aneurysm Associated with Acute-onset Portal Hypertension and Gastrointestinal Bleeding: Case Report and Literature Review.

Splenic arteriovenous fistula is an uncommon aetiology of portal hypertension, which has definitive treatment effectiveness and good prognosis. We report a case of portal hypertension and gastrointestinal bleeding in the absence of hepatic parenchymal disease in a 50 year-old woman with multiple pregnancies. Abdominal computed tomography and transabdominal arteriography recorded the presence of tortuous and aneurysmal splenic arteries and the premature filling of enlarged splenic veins, which are highly suggestive of splenic arteriovenous fistula. The above vascular abnormalities were successfully treated by transcatheter embolization. No recurrence or other complications were observed. In addition, a literature review concerning splenic arteriovenous fistula published in recent 30 years was performed to further our understanding of the management strategy on this entity.

Application of Proximal Splenic Vein Embolization to Interrupt Complicated Large Splenorenal Shunts in Adult Living Donor Liver Transplantation.

OBJECTIVE: The aim of the present study is to evaluate efficacy and safety of proximal splenic vein embolization (PSVE) for liver transplant recipients having complicated large splenorenal shunts (SRS). BACKGROUND: In adult living donor liver transplantation for a patient who has large splenorenal shunts (SRS), their interruption is utmost important to maintain adequate portal flow by avoidance of portal flow steal through the preexisting SRS. We effectively managed most of the recipients with surgical ligation and/or additional radiologic embolization using by intraoperative cine-portogram. However, when complete interruption is not achieved in a few recipients having complicated large SRS, it may leave a chance of lethal portal flow steal in the recipient afterward. METHODS: PSVE was performed in 13 patients between April 2014 and November 2017. We performed a retrospective analysis of preoperative images, postoperative graft and recipient outcomes, and presence of isolated portal hypertension. RESULTS: Ten patients underwent PSVE as an additional secondary method because of portal steal syndrome through the remaining SRS after surgical interruption and/or embolization, and 3 patients underwent PSVE only as a primary method of SRS interruption. In all 13 patients, portal steal on the final intraoperative cine-portogram completely disappeared after PSVE. All patients recovered with satisfactory regeneration of the partial liver graft without the reappearance of portosystemic collaterals, and there were no procedure-related complications. CONCLUSIONS: PSVE is an effective and safe procedure to secure adequate portal flow without portal steal for patients with complicated large SRS arising from multiple sites of the splenic vein or escaping to multiple terminal ends.

Portal Perfusion Through the Splenic Vein During Liver Procurement.

OBJECTIVES: Livers procured via donation after cardiac death have produced good outcomes. Some centers use only aortic perfusion; others add portal perfusion. MATERIALS AND METHODS: We report a series of organ procurements in which portal perfusion was performed via cannulation of the splenic vein instead of the inferior mesenteric vein in 4 donors after cardiac death and 2 donors after brain death. RESULTS: After declaration of death, donors were brought to the operating room and prepared and draped. During procurement, first the aorta was cannulated, and then the atrium or inferior vena cava was opened and perfusion was started.The spleen was mobilized, the splenic vein was dissected out and cannulated, and portal perfusion was performed with 2 L of University of Wisconsin solution. Five liver allografts were transplanted: 3 at our center, and 2 at outside centers. One liver from a donor after cardiac death was declined because of a high fat content. All 5 transplanted grafts showed good initial function; there was no sign of primary nonfunction, and no vascular or biliary complications developed. CONCLUSIONS: For livers from donors after cardiac death, cannulation of the splenic vein was easier than access via the inferior mesenteric vein. For donors after brain death, we also found this technique was suitable for livers with intra-abdominal adhesions or a small inferior mesenteric vein. Graft outcomes in this series were excellent.