Splanchnic venous thrombosis is a marker of cancer and a prognostic factor for cancer survival

Splanchnic Vein Thrombosis: The State-of-the-Art on Anticoagulant Treatment

Splanchnic vein thrombosis (SVT) is a rare type of venous thromboembolism occurring within the splanchnic venous system. Portal vein thrombosis is the most common presentation, while Budd-Chiari syndrome is the least common. Liver cirrhosis and abdominal solid cancer are the main local risk factors for SVT, whereas myeloproliferative neoplasms are the predominant systemic risk factors. Signs and symptoms of SVT are nonspecific and include abdominal pain, gastrointestinal bleeding, and ascites. Asymptomatic SVT is not uncommon, and the majority would be detected incidentally on routine abdominal imaging performed for the follow-up of liver diseases and tumors. The management of SVT aims to prevent thrombus progression, promote vessel recanalization, and prevent recurrent venous thromboembolism. Anticoagulation should be started early in order to increase the chances of vessel recanalization and reduce the risk of portal hypertension-related complications. Direct oral anticoagulants have been included in recent guidelines, as alternatives to vitamin K antagonists, after clinical stability has been reached; however, caution is required in patients with liver or kidney dysfunction. Treatment duration is based on the presence (or absence) and type (transient vs. permanent) of risk factors. This narrative review aims to summarize the latest evidence on SVT, with a particular focus on the anticoagulant treatment in special categories of patients (e.g., liver cirrhosis, solid cancer, myeloproliferative neoplasms, pancreatitis, incidentally detected SVT, Budd-Chiari syndrome, and chronic SVT).

Systemic Thrombolysis for Isolated Splenic Vein Thrombosis Secondary to Oral Contraceptives: A Case Report

Isolated splenic vein thrombosis (ISVT) is a very rare venous thromboembolism in the absence of pancreatic diseases, which can cause acute abdominal pain and chronic left-side portal hypertension. Herein, we reported a 40-year-old female patient who developed ISVT after taking oral contraceptives. Anticoagulation with oral rivaroxaban was the first-line choice of therapy in this case. Since then, abdominal pain alleviated, but she did not achieve vessel recanalization. Thus, a 7-day systemic thrombolysis with urokinase was given. Abdominal pain disappeared, but ISVT was not significantly improved. During follow-up period, long-term anticoagulation with oral rivaroxaban was given. Collectively, this case indicates the possibility of oral contraceptives as a risk factor of ISVT as well as anticoagulation combined with systemic thrombolysis as a choice of treatment for ISVT. Certainly, long-term follow-up is necessary in this case.

Natural history of cancer-associated splanchnic vein thrombosis

BACKGROUND

There is uncertainty in the management of cancer-associated isolated splanchnic vein thrombosis (SpVT).

OBJECTIVES

To describe the natural history of SpVT by cancer type and thrombus composition and to review anticoagulation (AC) practices and associated rates of usual-site venous thromboembolism (VTE), major and clinically relevant nonmajor bleeding (MB/CRNMB), recanalization/progression, and mortality.

METHODS

We performed a retrospective cohort study in patients with SpVT at 2 cancer care centers in Houston, Texas. We estimated the incidence of usual-site VTE and MB/CRNMB at 6 months using competing risk methods and examined venous patency in a subset of patients with repeat imaging. We assessed associations with mortality using Cox regression.

RESULTS

Among 15 342 patients with an incident cancer diagnosis from 2011 to 2020, we identified 298 with isolated SpVT. Patients with hepatocellular carcinoma (HCC) and SpVT (n = 146) had the highest disease prevalence (20%), lowest rate of AC treatment (2%), and similar rate of usual-site VTE (4.2%) vs those without SpVT (5.2%) at 6 months, though tumor thrombus vs bland was associated with worse overall survival. In patients with non-HCC bland SpVT (n = 114), AC (n = 37) was more common in those with non-upper gastrointestinal cancers and fewer comorbidities. AC was associated with more recanalization (44% vs 15%, P = .041) but no differences in usual-site VTE, MB/CRNMB, or mortality at 6 months.

CONCLUSION

Cancer-associated isolated SpVT is a common but heterogeneous thrombotic disease that is treated differently from usual-site VTE. Tumor thrombus is a negative prognostic factor. Initiation of AC in bland thrombi requires judicious consideration of thrombotic and bleeding risk.

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.

Cancer-associated splanchnic vein thrombosis: Clinical implications and management considerations

Splanchnic vein thrombosis (SVT), a thrombosis which involves the portal, mesenteric, and splenic veins, and the Budd-Chiari syndrome, represents an uncommon type of venous thromboembolism (VTE). Like with deep vein thrombosis of the lower extremities and pulmonary embolism, ample evidence suggests a significant association between SVT and cancer, particularly intra-abdominal solid malignancies (e.g. hepatobiliary and pancreatic cancers) and myeloproliferative neoplasms (MPN). Clinical symptoms of SVT in cancer patients can be ambiguous, and frequently attributed to the primary cancer itself. Alternatively, SVT may be asymptomatic and detected incidentally during cancer staging or follow-up evaluations. SVT can also precede the diagnosis of cancer and has been associated with poorer outcomes in patients with liver or pancreatic cancers. Therefore, an unprovoked SVT warrants a thorough evaluation for an underlying malignancy or MPN. Cancer-associated SVT carries a high risk of VTE extension, recurrence and bleeding. Extended anticoagulant treatment is often required in the absence of a high bleeding risk. Guidelines suggest treatment with either low molecular weight heparin (LMWH) or direct oral anticoagulants (DOACs), although available data on the safety and effectiveness of DOACs in these patients is limited. This comprehensive review outlines the epidemiology, pathogenesis, risk factors, and diagnosis of cancer-associated SVT and underscores the importance of comprehensive patient evaluation and evidence-based management.

Cancer-Associated Abdominal Vein Thrombosis

Cancer is associated with an increased risk of developing venous thromboembolism, due to its direct influence on the three pillars of Virchow's triad (e.g., compression on the blood vessels by the tumour, blood vessels invasion, and cytokine release), together with the effect of exogenous factors (such as chemotherapy, radiotherapy, surgery). In cancer patients, the risk of thrombosis at unusual sites, such as splanchnic, ovarian and renal vein thrombosis, is also increased. Abdominal vein thromboses are frequently incidental findings on abdominal imaging performed as part of the diagnostic/staging workup or the follow-up care of malignancies. There is little evidence on the management of unusual site venous thromboembolism in cancer patients since there are only a few specific recommendations; thus, the management follows the general principles of the treatment of cancer-associated deep vein thrombosis and pulmonary embolism. This narrative review summarises the latest evidence on cancer-associated abdominal vein thrombosis, i.e., thrombosis of the splanchnic, ovarian and renal veins.

Cancer-associated splanchnic vein thrombosis: Clinical features upon diagnosis and short-term outcomes

INTRODUCTION

The incidence of splanchnic vein thrombosis (SVT) in cancer patients has increased in recent years and its real clinical significance and management can be challenging. This study aimed to describe the clinical presentation and short-term outcomes of patients with cancer-associated SVT.

MATERIAL AND METHODS

This was a retrospective observational study of consecutive patients with cancer-associated SVT diagnosed during the period 2015-2020. The primary objective was to describe the clinical presentation of SVT. Patients were clinically classified into two groups based on the presence of symptoms on SVT diagnosis. The main outcomes were overall and SVT-related mortality, major and non-major bleeding rates, and the thrombosis recurrence rate in the first 30 days of follow-up.

RESULTS

This study enrolled 203 patients. Intra-abdominal tumors (76 %) and metastatic disease (68 %) predominated. A total of 79 (39 %) patients without symptoms were diagnosed with SVT during a scheduled radiological test and were classified as "asymptomatic", while 124 (61 %) patients presented some potential SVT symptoms and were considered as "symptomatic". Although the 30-day outcomes showed no significant differences between the two groups, mortality in the asymptomatic group was slightly lower compared to the symptomatic group (3 % vs. 10 %, p = 0.085).

CONCLUSIONS

Almost 40 % of cases of cancer-associated SVT are asymptomatic. There were no significant differences in short-term outcomes between the symptomatic and asymptomatic patients. More studies are required to better define long-term management and outcomes in these patients.

Arterial Resection for Pancreatic Cancer: Feasibility and Current Standing in a High-Volume Center

Background

Arterial resection (AR) during pancreatectomy for curative R0 resection of pancreatic ductal adenocarcinoma (PDAC) remains a controversial procedure with high morbidity.

Objective

To investigate the feasibility and oncological outcomes of pancreatectomy combined with AR at a high-volume center for pancreatic surgery.

Methods

We retrospectively analyzed our experience in PDAC patients, who underwent pancreatic resection with AR and/or venous resection (VR) between 2007 and 2021.

Results

In total 259 PDAC patients with borderline resectable (n = 138) or locally advanced (n = 121) PDAC underwent vascular resection during tumor resection. From these, 23 patients had AR (n = 4 due to intraoperative injury, n = 19 due to suspected arterial infiltration). However, 12 out of 23 patients (52.2%) underwent simultaneous VR including 1 case with intraoperative arterial injury. In comparison, 11 patients (47.8%) underwent AR only including 3 intraoperative arterial injury patients. Although the operation time and bleeding rate of patients with AR were respectively longer and higher than in VR, no significant difference was detected in postoperative complications between VR and AR (P = 0.11). The final histopathological findings of PDAC patients were similar, including M stage, regional lymph node metastases, and R0 margin resection. The mortality of the entire cohort was 6.2% (16/259), with a tendency to increase mortality in the AR cohort, yet without statistical significance (VR: 5% vs AR: 21.1%; P = 0.05). Although 19 (82.6%) patients had PDAC in the final histopathology, only 6 were confirmed to have infiltrated arteria. The microscopic distribution of PDAC in these infiltrated arterial walls on hematoxylin-eosin staining was classified into 3 patterns. Strikingly, the perivascular nerves frequently exhibited perineural invasion.

Conclusions

AR can be performed in high-volume centers for pancreatic surgery with an acceptable morbidity, which is comparable to that of VR. However, the likelihood of arterial infiltration seems to be rather overestimated, and as such, AR might be avoidable or replaced by less invasive techniques such as divestment during PDAC surgery.

Unmet clinical needs in the prevention and treatment of cancer-associated venous thromboembolism

Venous thromboembolism (VTE), which includes pulmonary embolism and deep vein thrombosis, is a leading cause of morbidity and mortality in patients with cancer. Based on accumulating evidence, the prophylaxis and treatment of cancer-associated VTE have been changed over the years. Recently, the introduction in clinical practice of the direct oral anticoagulants has radically changed the management of cancer-associated VTE for their easier use and non-inferior efficacy-safety profile compared to low-molecular-weight heparins. However, the heterogeneity of the cancer population in terms of site, type and stage of the malignancy, the presence of comorbidities, and the variability in cancer treatment and prognosis represent major challenges in the management of VTE in patients with cancer. In the present review, we will discuss clinical questions that represent unsolved issues in the setting of cancer-associated VTE and provide an overview on recent evidence on this topic: primary prophylaxis in ambulatory cancer patients treated with chemotherapy and in cancer surgical patients, need of long-term anticoagulation in cancer patients, treatment of VTE in cancer patients at increased bleeding risk and in special categories such as incidental VTE, splanchnic vein thrombosis or catheter-related thrombosis.

A 10-year Australian experience of rare intraabdominal venous thrombosis with comparison to deep vein thrombosis and pulmonary embolism

OBJECTIVE

Intra-abdominal venous thromboembolism is rare with heterogeneous management. We aim to evaluate these thrombosis and compare them to deep vein thrombosis and/or pulmonary embolism.

METHOD

A 10-year retrospective evaluation of consecutive venous thromboembolism presentations (January 2011-December 2020) at Northern Health, Australia, was conducted. A subanalysis of intraabdominal venous thrombosis involving splanchnic, renal and ovarian veins was performed.

RESULTS

There were 3343 episodes including 113 cases of intraabdominal venous thrombosis (3.4%) - 99 splanchnic vein thrombosis, 10 renal vein thrombosis and 4 ovarian vein thrombosis. Of the splanchnic vein thrombosis presentations, 34 patients (35 cases) had known cirrhosis. Patients with cirrhosis were numerically less likely to be anticoagulated compared to noncirrhotic patients (21/35 vs. 47/64, P  = 0.17). Noncirrhotic patients ( n  = 64) were more likely to have malignancy compared to those with deep vein thrombosis and/or pulmonary embolism (24/64 vs. 543/3230, P  < 0.001), including 10 patients diagnosed at time of splanchnic vein thrombosis presentation. Cirrhotic patients reported more recurrent thrombosis/clot progression (6/34) compared to noncirrhotic patients (3/64) (15.6 vs. 2.3 events/100-person-years; hazard ratio 4.7 (95% confidence interval 1.2-18.9), P  = 0.030) and other venous thromboembolism patients (2.6/100-person-years; hazard ratio 4.7, 95% confidence interval 2.1-10.7; P  < 0.001) with comparable major bleeding rates. All renal vein thrombosis were provoked including five malignant-related cases while three ovarian vein thrombosis occurred postpartum. No recurrent thrombotic or bleeding complications were reported in renal vein thrombosis and ovarian vein thrombosis.

CONCLUSION

These rare intraabdominal venous thromboses are often provoked. Splanchnic vein thrombosis (SVT) patients with cirrhosis have a higher rate of thrombotic complications, while SVT without cirrhosis was associated with more malignancy. Given the concurrent comorbidities, careful assessment and individualized anticoagulation decision is needed.

Vascular liver diseases: A sex-oriented analysis of the literature

Vascular liver diseases are an heterogenous group of diseases that collectively represent an important health issue in the field of liver diseases. This narrative review was elaborated by the Special Interest Group (SIG) "Gender in Hepatology" of the Italian Association for the Study of the Liver (AISF). We aimed to review the current knowledge regarding the potential role of biological sex in patients with vascular liver diseases such as splanchnic vein thrombosis, hepatic vein thrombosis, porto-sinusoidal vascular disorder, and hereditary hemorrhagic telangiectasia. As vascular liver diseases commonly affect young individuals, including women in childbearing age, we also included a specific section on the management of pregnancy in these challenging patients.

Shedding Light on the Pathogenesis of Splanchnic Vein Thrombosis

Splanchnic vein thrombosis is a rare but potentially life-threatening manifestation of venous thromboembolism, with challenging implications both at the pathological and therapeutic level. It is frequently associated with liver cirrhosis, but it could also be provoked by myeloproliferative disorders, cancer of various gastroenterological origin, abdominal infections and thrombophilia. A portion of splanchnic vein thrombosis is still classified as idiopathic. Here, we review the mechanisms of splanchnic vein thrombosis, including new insights on the role of clonal hematopoiesis in idiopathic SVT pathogenesis, with important implications from the therapeutic standpoint.

Incidence, risk factors, and evolution of venous thromboembolic events in patients diagnosed with pancreatic carcinoma and treated with chemotherapy on an outpatient basis

BACKGROUND

Pancreatic carcinoma is one of the tumors associated with a higher risk for thromboembolic events, with incidence rates ranging from 5% to 41% in previous retrospective series.

PATIENTS AND METHODS

We conducted a retrospective study in eleven Spanish hospitals that included 666 patients diagnosed with pancreatic carcinoma (any stage) between 2008 and 2011 and treated with chemotherapy. The main objective was to evaluate the incidence of venous thromboembolic events (VTE) in this population, as well as potential risk factors for thrombosis. The impact of VTE on mortality was also assessed.

RESULTS

With a median follow-up of 9.3 months, the incidence of VTE was 22.1%; 52% were diagnosed incidentally. Our study was unable to confirm the ability of the Khorana score to discriminate between patients in the intermediate or high risk category for thrombosis. The presence of VTE proved to be an independent prognostic factor associated with increased risk of death (HR 2.39, 95% CI 1.96-2.92). Symptomatic events correlated with higher mortality than asymptomatic events (HR 1.72; 95% CI, 1.21-2.45; p = 0.002), but incidental VTE, including visceral vein thrombosis (VVT), negatively affected survival compared to patients without VTE. Subjects who developed VTE within the first 3 months of diagnosis of pancreatic carcinoma had lower survival rates than those with VTE after 3 months (HR 1.92, 95% CI 1.30-2.84; p&lt;0.001).

CONCLUSIONS

Pancreatic carcinoma is associated with a high incidence of VTE, which, when present, correlates with worse survival, even when thrombosis is incidental. Early onset VTE has a particularly negative impact.

Multidisciplinary Care for the Prevention and Treatment of Venous Thromboembolism in Patients with Cancer-Associated Thrombosis (CAT): Impact of Educational Interventions on CAT-Related Events and on Patients' and Clinicians' Awareness

Cancer is a leading cause of death. Venous thromboembolism (VTE) is an often-overlooked cause of morbidity and mortality in cancer patients that can be readily prevented and treated. Actions are needed to reduce the morbidity and mortality of patients with cancer-associated thrombosis (CAT). There is a need to increase awareness of the impact of CAT on cancer patients' morbidity and mortality, on their quality of life and to understand the importance of more effective preventions and treatments of VTE in cancer patients. Moreover, it is of great importance to systematically assess the risk of VTE in regard to patients, cancer and treatment-related factors. Unfortunately, there are unmet clinical needs in the prevention and treatment of cancer-associated VTE. In this review, we discuss an action plan to ensure an increased awareness of and education on the issues that need to be addressed in order to improve the provision of appropriate prevention, early diagnosis and effective and safe treatment of VTE to all cancer patients and, ultimately, to reduce morbidity and mortality.

Clinical characteristics and disease course of splanchnic vein thrombosis in gastrointestinal cancers: A prospective cohort study

PURPOSE

Splanchnic vein thrombosis (SpVT) in solid tumors has not been well investigated. Therefore, the treatment guidelines for SpVT are not well established. We aimed to conduct this prospective study to investigate the clinical characteristics and risk factors influencing survival in patients with gastrointestinal cancer with SpVT.

MATERIALS AND METHODS

Fifty-one patients with gastrointestinal cancer diagnosed with SpVT were prospectively enrolled. The clinical characteristics and courses of SpVT were analyzed.

RESULTS

SpVT occurred in various clinical situations (at the time of initial cancer diagnosis or tumor recurrence after curative therapy, in the postoperative period, during chemotherapy, or in the period of end-of-life care). Among the total patients, 90.2% had no SpVT-related symptoms at initial SpVT diagnosis, and 82.4% did not receive any anticoagulation therapy. The clinical course of SpVT during the follow-up varied: (1) spontaneous resorption without any anticoagulation (47.1%), (2) resorption with anticoagulation (3.9%), (3) persistent thrombosis without progression (17.6%), and (4) SpVT extension (31.4%). Although the SpVT showed extension in some cases, most of them did not cause symptoms or had little impact on the patient's cancer treatment course. During the follow-up period, 23 patients died, all of which were caused by tumor progression. In the multivariable analysis, performance status and clinical situation at the time of SpVT diagnosis were significant prognostic factors.

CONCLUSIONS

Clinicians could adopt a strategy of close observation for incidentally detected SpVT in patients with gastrointestinal cancer. Anticoagulation should be considered only for SpVT cases selected strictly, weighing the risks and benefits.

Pancreaticobiliary Malignancies in the Emergency Room: Management of Acute Complications and Oncological Emergencies

Background

Management of pancreaticobiliary (PB) malignancies remains a clinical challenge. In this review, we focus on the management of oncological emergencies in PB malignancies and the potential complication of associated therapeutic interventions.

Methods

Biobliographic review of current evidence on the management of oncological emergencies, their potential complications, as well as synthesis of recommendations was performed. The pathogenesis, frequency, related symptoms as well as appropriate investigations are presented.

Results

The oncologic emergencies in PB patients were summarised in six categories: (1) hematological (including febrile neutropaenia, thrombocytopenia, coagulopathies), (2) gastrointestinal (gastric outlet and biliary obstruction, gastrointestinal bleeding), (3) thromboembolic events, (4) ascites, (5) metabolic disorders and (6) neurologic complications. The pathogenesis, frequency, related symptoms as well as appropriate investigations are also presented.

Conclusion

Patients with PB malignancies are at increased risk of a wide variation of medical emergencies. Clinical knowledge, early recognition and collaboration with the relevant specialties are critical to manage these complications effectively, tailoring overall management around the actual prognosis and individuals’ expectations.

Cancer-Associated Splanchnic Vein Thrombosis

Splanchnic vein thrombosis (SVT), which includes portal, mesenteric, and splenic vein thrombosis and the Budd-Chiari syndrome, is an infrequent manifestation of venous thromboembolism (VTE). Like typical site VTE, SVT is also frequently associated with cancer, particularly intra-abdominal solid malignancies and myeloproliferative neoplasms (MPNs). The clinical presentation of SVT is nonspecific. Symptoms may be related to the underlying malignancy, and thrombosis is incidentally diagnosed by imaging studies for cancer staging or follow-up in a substantial proportion of cases. The occurrence of SVT predicts worse prognosis in patients with liver or pancreatic cancer and, not uncommonly, SVT may precede the diagnosis of cancer. Therefore, the occurrence of an apparently unprovoked SVT should prompt careful patient evaluation for the presence of an underlying malignancy or MPN. Cancer patients carry a high risk of VTE extension and recurrence and long-term anticoagulant treatment is suggested in the absence of high risk of bleeding. Either LMWH or direct oral anticoagulants (DOACs) are suggested for the treatment of patients with cancer-related SVT, although limited experience is available on the use of DOACs in these settings. Vitamin K antagonists (VKAs) are suggested for the short and long-term treatment of SVT associated with MPN. This review outlines the epidemiological aspects, pathogenesis, risk factors, and diagnosis of cancer-associated SVT, and addresses questions regarding the management of this challenging condition.

Treatment of portal vein thrombosis: an updated narrative review

Portal vein thrombosis (PVT) is the most frequent among the splanchnic vein thrombosis, accounting for 90% of cases. More than half of PVT are provoked by liver cirrhosis, solid cancer or myeloproliferative neoplasms. The remaining cases are non-malignant non-cirrhotic PVT and include either unprovoked events or thrombosis secondary to other less common risk factors (e.g. abdominal surgery, intrabdominal inflammations/infections, or hormonal stimuli). Anticoagulant therapy in patients with acute symptomatic PVT should be started early after diagnosis, if no active bleeding, to obtain greater vessel recanalization and reduce the occurrence of portal-hypertension related complications. Gastroesophageal varices do not represent a contraindication to anticoagulant treatment, as long as adequate measures have been undertaken for the prophylaxis of gastroesophageal bleeding. Different treatment options (unfractionated or low molecular weight heparin, vitamin K antagonists and direct oral anticoagulants [DOACs]) can be considered. In this narrative review we will discuss the treatment of PVT in the three most common scenarios (cirrhosis-associated, cancer-associated and non-malignant non-cirrhotic PVT). We will also discuss the role of the DOACs and summarise recent guidelines on this topic.

Clinical history of cancer-associated splanchnic vein thrombosis

BACKGROUND

Cancer represents a risk factor for splanchnic vein thrombosis (SVT) and usual site venous thromboembolism (VTE).

OBJECTIVES

To compare characteristics and outcomes of patients with cancer-associated SVT and usual site VTE.

PATIENTS/METHODS

Patients with solid cancer and SVT were enrolled in an international, prospective registry between May 2008 and January 2012. The comparison cohort included (1:1 ratio) patients with solid cancer and usual site VTE treated at two thrombosis centers who had a minimum of 12 months follow-up at December 2019 or experienced one of the outcomes within 12 months follow-up. Recurrent VTE, major bleeding, and all-cause mortality were evaluated at 12-month follow-up.

RESULTS

A total of 264 patients (132 in each cohort) were enrolled. Patients with SVT were less likely to have metastatic disease (36.1% vs 72.5%) or receive cancer therapy at thrombosis diagnosis (29.6% vs 64.9%). The most frequent cancer types were hepatobiliary and pancreatic in the SVT cohort and gastrointestinal in the usual site VTE cohort. Fewer patients with SVT received anticoagulation (68.9% vs 99.2%), and treatment duration was shorter (6.0 vs 11.0 months). The cumulative incidence of major bleeding (2.3% vs 4.7%) was nonsignificantly lower in the SVT cohort, whereas recurrent thrombosis (4.7% vs 5.5%) and all-cause mortality (41.7% vs 39.4%) were comparable between the two cohorts.

CONCLUSIONS

The risk of recurrent thrombosis and bleeding appears to be similar in cancer patients with SVT and cancer patients with usual site VTE, despite some differences in baseline characteristics and anticoagulant treatment. Further prospective studies are warranted to confirm these findings.

Metastatic Infiltration of Anaplastic Carcinoma of the Pancreas Into the Portal Venous System: A Masquerading Cause of Expansive Portal Venous Thrombosis

BACKGROUND The portal vein thrombosis caused by a carcinoma of the pancreas or liver could be a diagnostic challenge. There are some cases which could be diagnosed only by observing changes in patients' clinical manifestations or imaging studies over time. CASE REPORT A 63-year-old man experienced exacerbation of chronic low back pain for 1 month, with abdominal distention. He was admitted to our hospital because abdominal ultrasonography and abdominal contrast-enhanced computed tomography performed at another hospital revealed an extensive thrombus in the portal, splenic, and superior mesenteric veins. Anticoagulation therapy with warfarin was started immediately on admission. Although no baseline disease, such as malignancies, coagulopathies, infections, or collagen diseases were revealed during the 12 days of his hospitalization, the thrombus gradually expanded, with the appearance of obstructive jaundice 8 months after admission. He was readmitted at that time for biopsy of intrahepatic tumors detected by abdominal computed tomography, which diagnosed metastasis of a carcinoma of unknown origin. Although chemotherapy was started, he died 11 months after his initial admission to our hospital. Autopsy revealed a tumorous lesion in the pancreatic head with almost complete replacement of the portal venous thrombus with a similar-appearing tumor. We confirmed the diagnosis of portal venous metastatic infiltration by undifferentiated pancreatic carcinoma, using histopathological examinations. CONCLUSIONS It is essential to consider portal venous metastatic infiltration of undiagnosed malignancy inducing local hypercoagulopathy as a possible cause of expansive portal venous thrombosis.

Screening for Cancer in Patients with Acute Venous Thromboembolic Disease

Active cancer causes approximately 25% of all acute events of venous thromboembolism (VTE). While most of the cancer diagnoses are known or clinically apparent at the time of VTE, care providers and patients may be worried about the 3 to 8% risk of occult cancer occurring in the year after VTE. Several studies have compared limited to extensive cancer screening after acute VTE, especially with the addition of abdominal computed tomography (CT) or whole-body PET-CT, with the hope to shorten the time to cancer diagnosis and lead to less advanced cancer stages. These studies have not shown improved clinical outcomes with an extensive screening, and have led to current recommendations of limited screening for cancer in patients with acute VTE, including unprovoked cases. Several risk assessment models have been developed to identify patients at greatest risk of occult cancer, however, with low discriminative performances and no current clinical usefulness. Some clinical situations may empirically deserve a more thorough cancer screening, such as unprovoked upper extremity deep vein thrombosis (DVT), bilateral leg DVT, descending leg DVT, or recurrent VTE during anticoagulation.

Cerebral and Splanchnic Vein Thrombosis: Advances, Challenges, and Unanswered Questions

Cerebral vein thrombosis (CVT) and splanchnic vein thrombosis (SVT) are two manifestations of venous thromboembolism (VTE) at unusual sites. They have an incidence at least 25-50 times lower than usual site VTE, but represent true clinical challenges. Recent evidence on the epidemiology, risk factors, prognosis, and treatment of CVT and SVT has been published in the last two decades, thus contributing to a better understanding of these diseases. The improvement in imaging techniques and a higher degree of clinical suspicion may have led to the observed increased frequency, whereas a better knowledge of provoking mechanisms could have contributed to reducing the proportion of events classified as unprovoked or idiopathic (13%-21% of CVT, 15%-27% of SVT). Few small randomized clinical trials and a number of observational studies, although hampered by heterogeneous therapeutic approaches, shed light on the safety and effectiveness of anticoagulant therapy in these populations. However, there are still some grey areas that warrant future research. In this narrative review, we discuss recent advances and therapeutic challenges in CVT and SVT.

Splanchnic vein thrombosis predicts worse survival in patients with advanced pancreatic cancer

INTRODUCTION

Pancreatic cancer is a thrombogenic malignancy with nearly half of venous thrombotic events occurring in the splanchnic circulation. The effect of splanchnic vein thrombosis on mortality in pancreatic cancer is unknown. We studied the effect of splanchnic vein thrombosis on mortality in veterans with advanced pancreatic adenocarcinoma, and explored the association of anticoagulant therapy on mortality and hemorrhage.

METHODS

Using International Classification of Diseases (ICD) codes, we identified eligible patients and outcomes in the Veterans Health Administration database. Using Cox proportional hazards regression, we analyzed the association between splanchnic vein thrombosis and mortality among patients with advanced pancreatic cancer. We used propensity score inverse probability-of-treatment weighting to balance the groups who did and did not receive anticoagulation. To understand the role of anticoagulant therapy, we used Cox proportional hazards regression to analyze mortality and competing risk analysis to assess the risk of hemorrhage.

RESULTS

Of the patients with advanced pancreatic cancer (N = 6164), 122 developed splanchnic vein thrombosis. Splanchnic vein thrombosis was associated with a two-fold increase in mortality, aHR 2.02, 95% CI 1.65-2.47. The finding held true after restricting the analysis to patients undergoing treatment for pancreatic cancer, and after adjusting for immortal time bias by a 30-day landmark analysis. Anticoagulant therapy did not affect mortality (aHR 0.99, 95% CI 0.65-1.51), and increased the risk of hemorrhage (aHR 2.7, 95% CI 1.02-7.07).

CONCLUSION

Splanchnic vein thrombosis predicts worse survival in patients with advanced pancreatic adenocarcinoma. Anticoagulant therapy may not mitigate this increased mortality, and increases the risk of hemorrhage.

Splanchnic Vein Thrombosis: Current Perspectives

Splanchnic vein thrombosis (SVT) including portal, mesenteric, splenic vein thrombosis and the Budd-Chiari syndrome, is a manifestation of unusual site venous thromboembolism. SVT presents with a lower incidence than deep vein thrombosis of the lower limbs and pulmonary embolism, with portal vein thrombosis and Budd-Chiari syndrome being respectively the most and the least common presentations of SVT. SVT is classified as provoked if secondary to a local or systemic risk factor, or unprovoked if the causative trigger cannot be identified. Diagnostic evaluation is often affected by the lack of specificity of clinical manifestations: the presence of one or more risk factors in a patient with a high clinical suspicion may suggest the execution of diagnostic tests. Doppler ultrasonography represents the first line diagnostic tool because of its accuracy and wide availability. Further investigations, such as computed tomography and magnetic resonance angiography, should be executed in case of suspected thrombosis of the mesenteric veins, suspicion of SVT-related complications, or to complete information after Doppler ultrasonography. Once SVT diagnosis is established, a careful patient evaluation should be performed in order to assess the risks and benefits of the anticoagulant therapy and to drive the optimal treatment intensity. Due to the low quality and large heterogeneity of published data, guidance documents and expert opinion could direct therapeutic decision, suggesting which patients to treat, which anticoagulant to use and the duration of treatment.

Update on Management of Portal Vein Thrombosis and the Role of Novel Anticoagulants

The clinical management of portal vein thrombosis (PVT) remains ambiguous due to its heterogeneous presentations and its associations with liver disease, malignancy, and hypercoagulable states. The natural history and clinical outcome of PVT are highly variable, dependent upon size, extent and degree of the thrombotic occlusion, as well as the physiological impact of patient comorbidities. While existing clinical guidelines consistently recommend low molecular weight heparin or vitamin K antagonist anticoagulation in cirrhotic patients with symptomatic acute PVT, management of asymptomatic and chronic PVT may need to be determined on a case-by-case basis, factoring in the state of underlying liver disease. In general, patients with PVT and underlying malignancy should be anticoagulated to alleviate symptoms and prevent recurrences that could disrupt the cancer management. However, existing clinical data does not support routine anticoagulation of cirrhotic patients with asymptomatic PVT in the absence of underlying cancer. While low molecular weight heparin and vitamin K antagonist remain the most commonly used agents in PVT, an emerging body of clinical evidence now suggests that direct-acting oral anticoagulants may be used safely and effectively in PVT. As such, direct-acting oral anticoagulants may offer a more convenient anticoagulation alternative for PVT management in future practice.

Venous Thromboembolism in Denmark: Seasonality in Occurrence and Mortality

Background  Many cardiovascular conditions exhibit seasonality in occurrence and mortality, but little is known about the seasonality of venous thromboembolism.

Methods  Using Danish registries, we identified all patients with deep vein thrombosis, pulmonary embolism, splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis during 1977–2016. We tallied monthly deaths occurring within 90 days of the venous thromboembolism diagnosis. We estimated peak-to-trough ratios and timing of the peak of both diagnoses and deaths summed over all years of the study period. The departure from 1.0 of the peak-to-trough ratio measures the intensity of any seasonal pattern.

Results  We estimated a peak-to-trough ratio of 1.09 (95% confidence interval: 1.07–1.11) for deep vein thrombosis and 1.22 (1.19–1.24) for pulmonary embolism occurrence. The peak-to-trough ratios for splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis occurrence were 1.10 (1.01–1.20), 1.19 (1.00–1.40), and 1.12 (1.07–1.17), respectively. The occurrence of all conditions peaked during winter or fall. In time trend analyses, the peak-to-trough ratio increased considerably for splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis occurrence. In associated mortality, the peak-to-trough ratio for deep vein thrombosis was larger (1.15, 1.07–1.23) than that for pulmonary embolism (1.04, 1.01–1.08).

Discussion  Excess winter risks were modest, but more marked for pulmonary embolism occurrence than for deep vein thrombosis occurrence. The seasonal pattern intensified throughout the study period for splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis. The winter peak in mortality following pulmonary embolism was smaller than that for deep vein thrombosis.

New Insight into AuNP Applications in Tumour Treatment and Cosmetics through Wavy Annuli at the Nanoscale

The purpose of this study is to probe the peristaltic propulsion of a non-Newtonian fluid model with suspended gold nanoparticles. The base fluid is considered to simulate blood using the Carreau fluid model. We model a small annulus as a tube with a peristaltic wave containing a clot propagating towards the tube wall. An external variable magnetic field is also considered in the governing flow. An approximation for long wavelengths and small Reynolds numbers is employed to formulate the governing flow problem. The resulting nonlinear equations are solved using a perturbation scheme. Series solutions are obtained for the velocity profile, temperature profile, pressure rise and streamlines. The results indicate an enhancement in the temperature profile that can be utilized in eradicating tumour cells.

Venous thrombosis in unusual sites: A practical review for the hematologist

Thrombosis of unusual venous sites encompasses a large part of consultative hematology and is encountered routinely by practicing hematologists. Contrary to the more commonly encountered lower extremity venous thrombosis and common cardiovascular disorders, the various thromboses outlined in this review have unique presentations, pathophysiology, workup, and treatments that all hematologists should be aware of. This review attempts to outline the most up to date literature on cerebral, retinal, upper extremity, hepatic, portal, splenic, mesenteric, and renal vein thrombosis, focusing on the incidence, pathophysiology, provoking factors, and current recommended treatments for each type of unusual thrombosis to provide a useful and practical review for the hematologist.

Risk of bleeding and arterial cardiovascular events in patients with splanchnic vein thrombosis in Denmark: a population-based cohort study

BACKGROUND

Little is known about adverse events following splanchnic vein thrombosis. Venous thromboembolism has been associated with increased risks of bleeding and arterial cardiovascular events. To learn more about the clinical course of splanchnic vein thrombosis, we examined the risks of bleeding and arterial cardiovascular events in patients with the disease, and compared them with the risks in patients with deep vein thrombosis (DVT) or pulmonary embolism (PE) and individuals from the general population.

METHODS

In this population-based cohort study, we used data for all patients with a diagnosis of splanchnic vein thrombosis recorded in the Danish National Patient Registry (DNPR) between Jan 1, 1994, and Nov 30, 2013 (cumulative source population 7 310 450 individuals). We created two comparison cohorts using data from the DNPR and the Civil Registration System for the same period: one of patients with DVT or PE and another of individuals from the general population. Comparison cohorts (ten comparators per patient with splanchnic vein thrombosis) were matched on sex, age, and calendar year of diagnosis. We calculated absolute risks and used proportional hazard regression to calculate adjusted hazard ratios (HRs) for the primary outcomes of bleeding and arterial cardiovascular events after splanchnic vein thrombosis diagnosis (or the index date for comparison cohorts).

FINDINGS

1915 patients with splanchnic vein thrombosis, 18 373 patients with DVT or PE, and 19 150 individuals from the general population were included in the study. Patients with splanchnic vein thrombosis were followed up for a median of 1 year (IQR 0·1-3·9). These patients had a high risk of bleeding in the 30 days after diagnosis, both in absolute terms (4·3% [95% CI 3·5-5·3]) and in adjusted models (HR 9·64 [95% CI 6·46-14·40] vs DVT or PE; 39·79 [19·44-81·46] vs general population). Bleeding risk was still significantly increased in patients with splanchnic vein thrombosis up to 1 year after diagnosis (HR 3·01 [95% CI 2·28-3·97] vs DVT or PE; 6·83 [4·83-9·65] vs general population), and remained elevated for up to 10 years compared with patients with DVT or PE (1·93 [1·12-3·34]) and for up to 19 years compared with the general population (5·90 [2·22-15·64]). The risk of arterial cardiovascular events in patients with splanchnic vein thrombosis was high in the year after diagnosis (absolute risk 3·3% [95% CI 2·6-4·2] up to 30 days; 7·0% [5·8-8·4] up to 31-365 days), and in adjusted models was significantly higher than in patients with DVT or PE (HR 7·05 [95% CI 4·74-10·48] up to 30 days; 2·10 [1·62-2·72] up to 31-365 days) and individuals from the general population (15·75 [9·26-26·79] and 3·17 [2·34-4·27], respectively). However, this risk did not remain significantly elevated above that of patients with DVT or PE after 1 year or the general population after 5 years.

INTERPRETATION

Patients with splanchnic vein thrombosis are at increased risk of adverse outcomes, particularly bleeding but also arterial cardiovascular events, for years after diagnosis compared with patients with DVT or PE and the general population. Physicians should be cognisant of these risks in patients with splanchnic vein thrombosis.

FUNDING

The Program for Clinical Research Infrastructure (PROCRIN), established by the Lundbeck Foundation and the Novo Nordisk Foundation.

Incidence, Management, and Implications of Visceral Thrombosis in Pancreatic Ductal Adenocarcinoma

BACKGROUND

Visceral or splanchnic thrombosis is defined as thrombi within the hepatoportal venous system, including portal (PV), mesenteric (MV), and splenic vein (SV), as well as thrombi in renal or gonadal veins. There are limited data to evaluate the prognostic significance, incidence, and clinical management of visceral thromboses in patients with pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

We conducted an analysis of 95 patients treated at Memorial Sloan Kettering Cancer Center with PDAC who had a visceral thrombosis.

RESULTS

A total of 153 visceral thromboses (VsT) were identified in 95 patients (n = 51, 54% woman). A total of 36 patients (37%) had locally advanced disease, and n = 59 (62%) had metastatic disease. Systemic therapies received included FOLFIRINOX (n = 57, 60%) and GC/PTX (n = 27, 28%). All VsT events were incidentally detected. Overall survival of cohort was 12.3 months (range, 10.2-14.4 months). Visceral thrombosis incidence in the cohort was as follows: portal vein (PV) (45%), MV (26%), SV (17%), and gonadal veins (8%). Time to develop first VsT was 4.3 months (range, 3-5.6 months), and time to death from VsT development was 1.87 months (range, 0.8-2.8 months). Forty-five patients (47%) developed a second VsT. Sixty percent had a Khorana risk score of > 3. Thirty-nine patients (41%) were treated with short-term anticoagulation (AC) (< 1 month) (low-molecular-weight heparin, n = 34). Forty-five patients (47%) were treated with long-term AC (> 1 month) (low-molecular-weight heparin, n = 32; 23 were transitioned to an oral anticoagulant). Twenty-two patients (23%) were not treated with AC. Eight patients (8%) had a bleeding complication from AC. Portal vein thrombosis had the shortest overall survival at 3.6 months (range, 2.3-4.8 months).

CONCLUSION

In PDAC, VsT can frequently present as an incidental finding on routine abdominal imaging. The most common location is PV, followed by MV and SV. We observed that AC is underutilized in this setting despite a low bleeding complication rate. PV was associated with the least overall survival of the VsT. Future large prospective studies should explore the role of AC and value in this setting.

Visceral Thromboses in Pancreas Adenocarcinoma: Systematic Review

Within gastrointestinal malignancies, primary hepatocellular carcinoma and pancreatic ductal adenocarcinoma (PDAC) are frequently associated with visceral thromboses (VT). Thrombus formation in the portal (PVT), mesenteric (MVT), or splenic vein (SVT) system leads to portal hypertension and intestinal ischemia. VT in PDAC may convey a risk of increased distal thrombosis and poses therapeutic uncertainty regarding the role of anticoagulation. An increasing number of reports describe VT associated with PDAC. It is possible that early diagnosis of these events may help reduce morbidity and speculatively improve oncologic outcomes. To perform a systematic review to study PVT, MVT, and SVT associated with PDAC, and to provide a comprehensive review. Medline/PubMed, Embase, Web of Science, Scopus, and the Cochrane Library. Data Extraction and Assessment: Two blinded independent observers extracted and assessed the studies for diagnosis of PVT, MVT, and SVT in PDAC. Studies were restricted to English-language literature published between 2007 and 2016. Eleven articles were identified. Five case reports and 7 retrospective studies were found, with a total of 127 patients meeting the inclusion criteria. The mean age at diagnosis was 64 years. PVT was found in 35% (n = 46), SVT in 52% (n = 65), and MVT in 13% (n = 15). Mean follow-up time was 26 months. Only 3 of the selected articles studied the impact of anticoagulation in VT. All patients with nonvisceral thrombosis (eg, deep-vein thrombosis, pulmonary emboli) were therapeutically treated; in contrast, patients with VT only rarely received treatment. VT in PDAC is a frequent finding at diagnosis or during disease progression. Evidence to guide treatment choices is limited, and current management is based on inferred experience from nononcologic settings. Anticoagulation appears to be safe in VT, with most of the large studies recommending a careful assessment for patients at a high risk of bleeding.

Biomarkers for the risk of thrombosis in pancreatic adenocarcinoma are related to cancer process

Background

Venous thrombo-embolic events (VTE) frequently occur in patients with pancreatic ductal adenocarcinoma (PDAC) and contribute to high morbidity and mortality.

Objectives

To determine whether VTE biomarkers are related to cancer, inflammation or precancerous states and to assess their relevance to predict VTE in PDAC.

Patients and Methods

We compared VTE biomarkers in patients with PDAC (n = 42), intraductal papillary mucinous neoplasm of the pancreas (IPMN, n = 48) or chronic pancreatitis (n = 50). PDAC patients were followed-up for 6 months.

Results

Factor VIII, D-dimers, von Willebrand factor, free tissue factor pathway inhibitor and microvesicle-tissue factor (MV-TF) activity were higher in PDAC patients compared to patients with IPMN or chronic pancreatitis. PDAC patients with metastasis presented higher D-dimers and MV-TF activity compared to patients with localized lesions, but elevation of D-dimers was dependent on tumor size. In multivariate analysis, elevated D-dimers (≥2.16 µg/mL) or MV-TF activity (≥2.37 pg/mL) were significant risk factors for VTE in PDAC patients, after adjustment for age and sex (HR 4.9 [1.0-23.1] or HR 10.5 [1.5-72.4], mean [interquartile range], respectively). Cumulative probability of VTE at 6 months was higher in patients with elevated D-dimers (56.3% vs 15.6%, p = 0.009) and in patients with high MV-TF activity (74.3% vs 21.7%, p = 0.01).

Conclusions

VTE biomarkers including D-dimers and MV-TF activity are not related to inflammation but rather to cancer process and dissemination. D-dimers and MV-TF activity are associated to future VTE in PDAC patients and could help identify patients who could benefit from thromboprophylaxis.

Meeting Report EuroG20 Meeting on Cancer-Associated Thrombosis (CAT) Bergamo, Italy 7 April 2016

The EuroG20 meeting on cancer-associated thrombosis (CAT) convened in Bergamo, Italy on 7 April 2016 to discuss a selection of controversial topics in CAT management. This satellite meeting besides ICTHIC in Bergamo has the objective to propose an European Guidance on CAT in various complex situations where evidence-based guidelines are lacking, driven by eminence-based thoughts of 20 experts and key opinion leaders in thrombosis from EU area and 8 experts from the rest of the world.

Approach to thrombosis at unusual sites: Splanchnic and cerebral vein thrombosis

Splanchnic vein thrombosis (SVT) and cerebral vein thrombosis (CVT) are two manifestations of unusual site venous thromboembolism (VTE). SVT includes thrombosis in the portal, mesenteric or splenic veins, and the Budd-Chiari syndrome. CVT encompasses thrombosis of the dural venous sinuses and thrombosis of the cerebral veins. Unusual site VTE often represents a diagnostic and therapeutic challenge because of the heterogeneity in clinical presentation, the limited evidence available in the literature on the acute and long-term prognosis of these diseases, and the lack of large randomized controlled trials evaluating different treatment options. This narrative review describes the approach to patients with SVT or CVT by examining the diagnostic process, the assessment of potential risk factors and the appropriate anticoagulant treatment.

Impact of Classical Risk Factors for Arterial or Venous Thrombosis in Patients With Antiphospholipid Syndrome

There are classical risk factors associated with arterial thrombosis (AT) or venous thromboembolic disease (VTD). However, less is known about these risk factors and AT or VTD episodes in patients with antiphospholipid syndrome (APS). Our aim was to elucidate whether APS-related thrombotic episodes are associated with the same risk factors as the non-APS population. We gathered demographics, medical history, complications, and causes of death associated with the risk factors for AT or VTD in patients with APS. We analyzed 677 thrombotic events in 386 patients. Type 2 diabetes mellitus and grade 3 obesity were associated with VTD instead of AT. There were no significant differences between the groups for almost all laboratory tests analyzed, although lupus anticoagulant was significantly higher in the VTD group. We suggest that thrombosis in APS is due to the APS itself and that the risks factors for AT or VTD do not have a main role. Our findings may have an ethnical background. Therefore, it may be difficult to elaborate predictive thrombotic clinical scores applicable to patients with different ethnical background.

Clinical manifestations and imaging tools in the diagnosis of splanchnic and cerebral vein thromboses

Splanchnic vein thrombosis (SVT) and cerebral vein thrombosis (CVT) are uncommon manifestation of venous thromboembolism (VTE), occurring less frequently than deep vein thrombosis of the lower extremities and pulmonary embolism. SVT encompasses portal vein thrombosis, mesenteric vein thrombosis, splenic vein thrombosis and the Budd-Chiari syndrome. It is therefore a heterogeneous disease, with differences in clinical manifestations according to the site of thrombosis. CVT includes thrombosis of the cortical or deep cerebral veins and thrombosis of the major dural venous sinuses. Clinical presentation is variable, with a wide spectrum of signs and symptoms that can mimic other cerebral diseases. There are no clinical algorithms or specific laboratory tests that can guide in the identification of SVT and CVT; therefore, the diagnosis relies exclusively on imaging tests. Conventional angiography once was the gold standard for the diagnosis of SVT and CVT, but it is rarely used nowadays. Abdominal ultrasound (US), computed tomography (CT) and magnetic resonance (MR) with angiography are currently used for the diagnosis of SVT; while cerebral CT and MR with angiography are currently used for the diagnosis of CVT. These imaging tests have different sensitivities/specificities and different advantages/disadvantages that should be kept into consideration when choosing the appropriate imaging test based on the suspected site of thrombosis. This narrative review summarizes the clinical and diagnostic approach to SVT and CVT.

Splanchnic vein thrombosis in myeloproliferative neoplasms: risk factors for recurrences in a cohort of 181 patients

We retrospectively studied 181 patients with polycythaemia vera (n=67), essential thrombocythaemia (n=67) or primary myelofibrosis (n=47), who presented a first episode of splanchnic vein thrombosis (SVT). Budd–Chiari syndrome (BCS) and portal vein thrombosis were diagnosed in 31 (17.1%) and 109 (60.3%) patients, respectively; isolated thrombosis of the mesenteric or splenic veins was detected in 18 and 23 cases, respectively. After this index event, the patients were followed for 735 patient years (pt-years) and experienced 31 recurrences corresponding to an incidence rate of 4.2 per 100 pt-years. Factors associated with a significantly higher risk of recurrence were BCS (hazard ratio (HR): 3.03), history of previous thrombosis (HR: 3.62), splenomegaly (HR: 2.66) and leukocytosis (HR: 2.8). Vitamin K-antagonists (VKA) were prescribed in 85% of patients and the recurrence rate was 3.9 per 100 pt-years, whereas in the small fraction (15%) not receiving VKA more recurrences (7.2 per 100 pt-years) were reported. Intracranial and extracranial major bleeding was recorded mainly in patients on VKA and the corresponding rate was 2.0 per 100 pt-years. In conclusion, despite anticoagulation treatment, the recurrence rate after SVT in myeloproliferative neoplasms is high and suggests the exploration of new avenues of secondary prophylaxis with new antithrombotic drugs and JAK-2 inhibitors.

[Splanchnic venous thrombosis: A monocentric study of 31 cases]

INTRODUCTION

Splanchnic vein thrombosis (SVT) denotes thrombosis of the hepatic venous system and of the extrahepatic portal system. They are often the manifestation of one or more underlying prothrombotic states and can sometimes present problems of therapeutic care.

METHODS

We report a monocentric study of 31 cases of SVT observed in an internal medicine department between January 2006 and June 2012. Epidemiological, clinical, laboratory, therapeutic and outcome data were analyzed.

RESULTS

There was a slight female predominance (sex-ratio: 1.2). Median patient age at diagnosis was 37 years. Most cases of SVT were chronic (61.2%). Abdominal pain was the predominant symptom in acute cases while the predominant signs in chronic forms were signs of portal hypertension. Extrasplanchnic thrombosis was noted in seven patients (22.5%). Behçet's disease was the most common etiology (32%). The treatment was based on anticoagulants and corticosteroids and immunosuppressants when an inflammatory etiology was found. The average follow-up was 17 months. There were five deaths (16%).

CONCLUSION

SVT often reflects the existence of a disease and/or an underlying prothrombotic state that should be identified to adapt the treatment and to avoid fatal complications.

Small clots with large impact

In this issue of Blood, Kirstine Søgaard and colleagues report on the relevance of splanchnic vein thrombosis (SVT) as a marker of occult malignant disease.