Extensive Computed Tomography versus Limited Screening for Detection of Occult Cancer in Unprovoked Venous Thromboembolism: A Multicenter, Controlled, Randomized Clinical Trial

Occult cancer in patients with unprovoked venous thromboembolism: Rationale, design, and methods of the VaLRIETEs study and the SOME-RIETE trial

BACKGROUND

Unprovoked venous thromboembolism (VTE) is considered when no clear major provoking factor for VTE is identified. Although the 1-year risk of diagnosing new cancer in these patients can be as high as 5%, the benefits of extensive screening remain uncertain. It is possible that in a risk-enriched population of patients, screening yields benefit. Recently, the RIETE score, a composite score including sex, age, chronic pulmonary disease, anemia, platelet count and previous VTE, was found to improve risk prediction for identification of occult cancer in patients with unprovoked VTE. As for screening tests, whole body 18F-fluorodeoxyglucose Positron Emission/Computed Tomography (18F-FDG PET/CT) is a promising and sensitive tool for occult cancer screening.

METHODS

This manuscript summarizes the rationale and design of 2 prospective studies in patients with unprovoked symptomatic VTE: (1) ValRIETE is an international, multicenter, prospective, adaptative, cohort study that plans to include 1,550 patients; the adaptive design permits a sample size increase depending on the results of the predefined interim analysis. This study will enable the external validation of the RIETE score, with several ancillary aims related to additional clinical and biomarker predictors. Recruitment began in December 2022. (2) SOME-RIETE is an open-label, randomized, multicenter clinical trial that plans to enroll 650 patients with a RIETE score ≥3 to compare limited screening with limited screening plus whole body 18F-FDG PET/CT. The primary outcome is cancer diagnosis within 3 months after VTE event. Secondary outcomes include cancer diagnosis and mortality at 12 months.

CONCLUSIONS

This study provides clinically meaningful data on and the utility of extended screening of cancer by 18F-FDG PET/CT.

STUDY REGISTRATION

VaLRIETE study: ethics committee of the Virgen del Rocio University Hospital, Sevilla (Spain). https://www.juntadeandalucia.es/salud/portaldeetica/xhtml/inicio/inicio.iface (1687-N-22).

TRIAL REGISTRATION

SOME-RIETE:ClinicalTrials.gov (NCT03937583).

[Utility of abdominal ultrasound in screening occult malignancy in the etiological study of idiopathic venous thromboembolism]

PURPOSE

To determine the sensibility of abdominal ultrasound (US) in the screening of occult cancer in patients with idiopathic venous thromboembolism (iVTE). To evaluate its sensitivity and specificity in different subgroups of patients with iVTE, in order to detect potential beneficiaries in whom the abdominal US screening may have greater diagnostic benefit. Descriptive analysis of the use of abdominal US in these patients, and evaluation of its impact on their management.

MATERIAL AND METHODS

We retrospectively searched all patients with confirmed iVTE (by Doppler-US, by CT angiography or V/Q scintigraphy) between 2011-2014, which had been performed an abdominal US for screening of occult malignancy as part as their aetiology study of VTE. As reference we set a follow-up period of 2years.

RESULTS

280 patients were found, and 209 were included after inclusion and exclusion criteria were applied. Abdominal US was positive for malignancy in 7 patients (3.3%). The sensitivity and specificity for cancer detection were 43.75% and 99.48%, respectively. Cancer was found in 16 patients in the 2-year follow-up (7.6%). No significant differences were found in the different subgroups of patients. Nevertheless, 28 patients (13.4%) were diagnosed of other cause of VTE during aetiology study, mainly hypercoagulability disorders.

CONCLUSIONS

Abdominal US for screening of occult malignancy in patients with iVTE is a very specific test but has low sensitivity, which compromises its utility as a routine screening test in these patients. Its use could be optimised by performing it only in selected subgroups of patients that need to be established in future research.

Development of a Predictive Model of Occult Cancer After a Venous Thromboembolism Event Using Machine Learning: The CLOVER Study

Background and Objectives: Venous thromboembolism (VTE) can be the first manifestation of an underlying cancer. This study aimed to develop a predictive model to assess the risk of occult cancer between 30 days and 24 months after a venous thrombotic event using machine learning (ML). Materials and Methods: We designed a case-control study nested in a cohort of patients with VTE included in a prospective registry from two Spanish hospitals between 2005 and 2021. Both clinically and ML-driven feature selection were performed to identify predictors for occult cancer. XGBoost, LightGBM, and CatBoost algorithms were used to train different prediction models, which were subsequently validated in a hold-out dataset. Results: A total of 815 patients with VTE were included (51.5% male and median age of 59). During follow-up, 56 patients (6.9%) were diagnosed with cancer. One hundred and twenty-one variables were explored for the predictive analysis. CatBoost obtained better performance metrics among the ML models analyzed. The final CatBoost model included, among the top 15 variables to predict hidden malignancy, age, gender, systolic blood pressure, heart rate, weight, chronic lung disease, D-dimer, alanine aminotransferase, hemoglobin, serum creatinine, cholesterol, platelets, triglycerides, leukocyte count and previous VTE. The model had an ROC-AUC of 0.86 (95% CI, 0.83-0.87) in the test set. Sensitivity, specificity, and negative and positive predictive values were 62%, 94%, 93% and 75%, respectively. Conclusions: This is the first risk score developed for identifying patients with VTE who are at increased risk of occult cancer using ML tools, obtaining a remarkably high diagnostic accuracy. This study's limitations include potential information bias from electronic health records and a small cancer sample size. In addition, variability in detection protocols and evolving clinical practices may affect model accuracy. Our score needs external validation.

Newly Diagnosed Cancer After Diagnosis of Venous Thromboembolism - Insights From the COMMAND VTE Registry-2

BACKGROUND

Previous randomized clinical trials did not support a benefit of screening for occult cancer after diagnosis of venous thromboembolism (VTE), although screening may be of potential benefit for selected high-risk patients.

METHODS AND RESULTS

The COMMAND VTE Registry-2 enrolled consecutive patients with acute symptomatic VTE between 2015 and 2020 from 31 centers across Japan. The 3,706 patients in the registry without known active cancer at the time of VTE diagnosis were divided into 2 groups: those with (n=250) and without (n=3,456) newly diagnosed cancer during the follow-up period. The cumulative incidence of newly diagnosed cancer was 1.5% at 30 days, 3.7% at 1 year, and 7.0% at 3 years. The multivariable Cox proportional hazard model demonstrated that older age (hazard ratio [HR] 1.02 per 1 year increase; 95% confidence interval [CI] 1.01-1.03; P<0.001), a history of cancer (HR 3.57; 95% CI 2.73-4.64; P<0.001), autoimmune disorders (HR 1.48; 95% CI 1.06-2.02; P=0.02), a history of major bleeding (HR 1.64; 95% CI 1.04-2.48; P=0.04), and the absence of transient provoking risk factors for VTE (HR 1.44; 95% CI 1.08-1.92; P=0.01) were independently associated with newly diagnosed cancer.

CONCLUSIONS

The incidence of newly diagnosed cancer after VTE diagnosis was 3.7% at 1 year, and several independent risk factors for newly diagnosed cancer after VTE diagnosis were identified.

External validation of the RIETE and SOME scores for occult cancer in patients with venous thromboembolism: a multicentre cohort study

INTRODUCTION

Venous thromboembolism (VTE) may be the first sign of an undiagnosed cancer. The RIETE and SOME scores aim to identify patients with acute VTE at high risk of occult cancer. In the present study, we evaluated the performance of both scores.

METHODS

The scores were evaluated in a retrospective cohort from two centers. The area under the receiver-operating characteristics curve (AUC) evaluated the discriminatory performance.

RESULTS

The RIETE score was applied to 815 patients with provoked and unprovoked VTE, of whom 56 (6.9%) were diagnosed with cancer. Of the 203 patients classified as high-risk, 18 were diagnosed with cancer, representing 32.1% (18/56) of the total cancer diagnoses. In the group of 612 low-risk patients, 67.9% of the cancer cases were diagnosed (38/56). Sensitivity, specificity, negative and positive predictive values, and AUC were 32%, 76%, 94%, 9%, and 0.430 (95% confidence interval [CI], 0.38‒0.47), respectively. The SOME score could be calculated in 418 patients with unprovoked VTE, of whom 33 (7.9%) were diagnosed with cancer. Of the 45 patients classified as high-risk, three were diagnosed with cancer, representing 9.1% (3/33) of the total cancer diagnoses. In the group of 373 low-risk patients, 90.9% of the cancer cases were diagnosed (30/33). Sensitivity, specificity, negative and positive predictive values, and AUC were 33%, 88%, 94%, 20%, and 0.351 (95% CI, 0.27‒0.43), respectively.

CONCLUSIONS

The performance of both scores was poor. Our results highlight the need to develop new models to identify high-risk patients who may benefit from an extensive cancer screening strategy.

Superficial Vein Thrombosis in an Asymptomatic Case of Cholangiocarcinoma with Recent History of COVID-19

The COVID-19 pandemic brought into prominence several emergent medical and surgical entities, but, also, it served as trigger and contributor for numerous apparently unrelated ailments such as arterial and venous thromboembolic complications. Additional risk factors for these thrombotic traits may be concurrent (known or unknown) malignancies, including at hepatic level. Among these, cholangiocarcinoma (CCA), a rare cancer of intra- and extra-hepatic biliary ducts, represents a very aggressive condition that typically associates local and distant advanced stages on first presentation requiring a prompt diagnosis and a stratified management. This neoplasia has been reported to present a large spectrum of paraneoplastic syndromes in terms of dermatologic, renal, systemic, neurologic, endocrine, and cardiovascular settings, that, overall, are exceptional in their epidemiologic impact when compared to other cancers. Our aim was to introduce a most unusual case of CCA-associated distant thrombosis in a male adult who initially was considered to experience COVID-19-related thrombotic features while having a history of obesity and bariatric surgery. This is a hybrid type of paper: this clinical vignette is accompanied by two distinct sample-focused analyses as a basis for discussion; they each had different methods depending on their current level of statistical evidence. We only included English-published articles in PubMed, as follows: Firstly, we conducted a search of reports similar to the present case, regarding distant vein thrombosis in CCA, from inception until the present time. We performed a literature search using the keywords "cholangiocarcinoma", "thrombosis", and "Trousseau's syndrome" and identified 20 cases across 19 original papers; hence, the current level of evidence remains very low Secondly, we searched for the highest level of statistical evidence concerning the diagnosis of venous thrombosis/thromboembolism in patients who underwent COVID-19 infection (key search terms were "COVID-19", alternatively, "coronavirus", and "SARS-CoV-2", and "thrombosis", alternatively, "thromboembolism") and included the most recent systematic reviews and meta-analyses that were published in 2024 (from 1 January 2024 until 8 July 2024). After excluding data on vaccination against coronavirus or long COVID-19 syndrome, we identified six such articles. To conclude, we presented a probably unique case of malignancy with an initial manifestation consisting of recurrent superficial vein thrombosis under anticoagulation therapy, with no gastrointestinal manifestations, in a patient with a notable history for multiple episodes of SARS-CoV-2 infection and a prior endocrine (gastric) surgery. To our knowledge, this is the first identification of a CCA under these specific circumstances.

The Conundrum of Cancer-Associated Thrombosis: Lesson Learned from Two Intriguing Cases and Literature Review

The correlation between cancer and venous thromboembolism (VTE) is solid, whereas the knowledge about cancer-related arterial thromboembolism (ATE) still needs a deeper investigation to clarify its pathogenesis. We describe two cases that represent useful hints for a comprehensive review of the thrombotic issue. A 75-year-old man with advanced rectal cancer treated with fluoropyrimidines suffered two catheter-related VTE events managed according to current guidelines. There was no indication for "extended" anticoagulant therapy for him, but during antithrombotic wash-out and fluoropyrimidines plus panitumumab regimen, he suffered a massive right coronary artery (RCA) thrombosis. Another patient with no cardiovascular (CV) risk factors and affected by advanced bladder cancer was treated with a platinum-containing regimen and suffered an acute inferior myocardial infarction 2 days after chemotherapy administration. He was successfully treated with primary Percutaneous Transluminal Coronary Angioplasty of RCA, discontinuing platinum-based therapy. Our observations raise the issue of cancer-associated thrombosis (CAT) complexity and the potential correlation between arterial and venous thrombotic events. Moreover, physicians should be aware of the thrombotic risk associated with anticancer therapies, suggesting that an appropriate prophylaxis should be considered.

[Thromboembolic disease and cancer: Attitude and practice of general practitioners. A qualitative study]

INTRODUCTION

Cancer is a major public health problem in France. Idiopathic venous thromboembolic disease may be one of the modes of discovery. Few studies have been performed on this subject in primary care. The general practitioner plays a key role in the diagnosis for which a more codified approach seems desirable. The aim was to study how general practitioners conceive the search for cancer in patients with idiopathic venous thromboembolic disease in primary care.

METHOD

A qualitative study, inspired by the grounded theory approach, was carried out using semi-structured interviews with 12 established general practitioners. It was conducted from May to July 2022. The interview guide was developed based on data from the literature.

RESULTS

Idiopathic venous thromboembolic disease as a mode of cancer discovery in primary care was a well-known topic among general practitioners but remained a difficult exercise in practice. Our study revealed similarities in their practices: a complete anamnesis, clinical examination, verification of screening tests, and finally a TAP scan. They emphasized the importance of collaboration with angiologists and asked for a more codified management.

DISCUSSION

The question of etiology of cancer remains unanswered. General practioners would like to be made aware of a common, codified attitude. This raises the question of the applicability of the recommendations. The aim is to avoid misdiagnosing a cancer or delaying a diagnosis, while at the same time, not unnecessarily exposing certain patients to excessive investigations when these are not needed. So, it is time to think about better dissemination of recommendations, tools to help GPs easily finding what they need among the multitude of existing recommendations and tools, to establish better collaboration between general practice and hospital medicine, and between general practice and specialist medicine in order to improve cancer diagnosis as early as possible.

CT imaging for occult malignancy in patients with unprovoked venous thromboembolism (VTE) in a tertiary centre: is it worthwhile?

BACKGROUND

Investigating patients with unprovoked venous thromboembolism (uVTE) for occult malignancy can prove a diagnostic dilemma and imaging is often used extensively in this patient group.

AIMS

The primary objective of this study was to determine the incidence of malignancy on CT and other imaging over a 10-year period. A secondary objective was to evaluate the role of laboratory and other non-imaging tests performed.

METHODS

A retrospective key word search of our hospital's imaging system was performed to identify patients with unprovoked DVT/PE over the last 10 years. All imaging, histology, endoscopy, laboratory tests, and clinical follow-up over 2 years were analysed. Patients with provoked VTE were excluded.

RESULTS

150 patients had uVTE. 9 patients were diagnosed with occult malignancy by different investigations on index hospital admission (3 patients) or subsequently on clinical follow-up (6 patients). Mean age of patients was 62 years. 116 patients had CT body imaging. The incidence of malignancy diagnosed by initial CT imaging was 1.7% with a sensitivity of 22%, specificity 87%, and PPV 12.5%. Overall incidence of malignancy identified by imaging alone during the index hospital admission was 2%. Total incidence of malignancy including index admission and follow-up was 6%. Median time to cancer diagnosis was 12 months.

CONCLUSION

CT imaging had a low yield for diagnosing malignancy. Extensive imaging strategies increase cost and radiation exposure without improving mortality. Clinical follow-up, history taking, and physical examination guiding appropriate investigations remain the best tool for unmasking occult malignancy in patients with uVTE.

Neutrophil extracellular trap formation is an independent risk factor for occult cancer in patients presenting with venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE), particularly unprovoked VTE, is associated with occult cancer. The optimal screening regimen remains controversial. Neutrophil extracellular traps (NETs) are implicated in cancer-associated thrombosis, and elevated biomarkers of NET formation are associated with poor prognosis.

OBJECTIVES

To investigate the association between NET formation and occult cancer in patients with VTE.

METHODS

Blood biomarkers associated with NETs and neutrophil activation (nucleosomal citrullinated histone H3 [H3Cit-DNA], cell-free DNA, and neutrophil elastase) were quantified in patients with VTE. The primary outcome was cancer diagnosed during a one-year follow-up.

RESULTS

This study included 460 patients with VTE, of which 221 (48%) had isolated deep vein thrombosis. Forty-three patients had active cancer at inclusion and were excluded from the primary analysis Cancer during follow-up was diagnosed in 29 of 417 (7.0%) patients. After adjustment for age and unprovoked VTE, the hazard ratio of cancer during follow-up per 500 ng/mL increase of H3Cit-DNA was 1.79 (95% CI, 1.03-3.10). Furthermore, patients with cancer-associated VTE (known active cancer or cancer diagnosed during follow-up) had higher levels of H3Cit-DNA than cancer-free patients with VTE after adjustment for age, hemoglobin, gender, chronic obstructive pulmonary disease, previous cancer, and start of anticoagulant treatment (odds ratio 2.06 per 500 ng/mL increase of H3Cit-DNA [95% CI, 1.35-3.13]).

CONCLUSIONS

H3Cit-DNA is an independent predictor for occult cancer in patients with VTE and elevated in cancer-associated VTE, suggesting that H3Cit-DNA is potentially a useful diagnostic marker for cancer in patients with VTE and that elevated NET formation is a hallmark of cancer-associated VTE.

Screening for occult cancer after unprovoked venous thromboembolism: Assessing the current literature and future directions

While significant evidence has established an increased rate of thrombosis in patients with cancer, the risk of occult malignancy in the setting of an unprovoked thrombosis is less clear. Despite continued interest in developing an effective screening system for occult malignancy following unprovoked venous thromboembolism (VTE), discrepancies in the literature and guideline recommendations leave providers uncertain whether to screen or perform further diagnostics for this patient population. Evidence suggests that screening for malignancy can detect cancer sooner in patients with unprovoked VTE, but there is a lack of high-quality evidence demonstrating improvements in survival who receive early detection. In the following manuscript, we summarize VTE in relation to cancer epidemiology and pathophysiology. Our literature review summarizes the spectrum of testing strategies for occult malignancy following unprovoked VTE, including biomarker detection methods and various imaging approaches. We evaluate the benefit of additional diagnostic strategies, review current guidelines on the issue, and provide guidance to the reader on the best practice for investigating undiagnosed malignancy in patients with unprovoked VTE.

Venous Thromboembolism and Risk of Cancer in Users of Low-Dose Aspirin: A Danish Population-Based Cohort Study

Background  Aspirin may reduce the risk of cancer, particularly gastrointestinal cancer, and venous thromboembolism (VTE). VTE can be the first symptom of occult cancer, but whether it is also a marker of occult cancer in aspirin users remains unknown. Therefore, we investigated the risk of cancer subsequent to VTE among users of low-dose aspirin.

Methods  We conducted a population-based cohort study using data from Danish health registries for the years 2001 to 2018. We identified all patients with a first-time diagnosis of VTE who also redeemed a prescription for low-dose aspirin (75–150mg) within 90 days prior to the first-time VTE. We categorized aspirin users by the number of prescriptions filled as new users (<5 prescriptions), short-term users (5–19 prescriptions), and long-term users (>19 prescriptions). We computed the absolute cancer risks and standardized incidence ratios (SIRs) for cancer using national cancer incidence rates.

Results  We followed-up 11,759 users of low-dose aspirin with VTE. Long-term users comprised 50% of aspirin users. The 1-year absolute risk of cancer was 6.0% for new users and 6.7% for short-term and long-term users, with corresponding SIRs of 3.3 (95% confidence interval [CI]: 2.8–4.0), 3.2 (95% CI: 2.9–3.7), and 2.8 (95% CI: 2.6–3.2), respectively. After the first year of follow-up, the SIR decreased to 1.2 (95% CI: 1.1–1.4) for new users, 1.1 (95% CI: 1.1–1.3) for short-term users, and 1.1 (95% CI: 1.0–1.2) for long-term users.

Conclusion  VTE may be a harbinger of cancer, even in users of low-dose aspirin, regardless of duration of use.

Effect of testing for cancer on cancer- or venous thromboembolism (VTE)-related mortality and morbidity in people with unprovoked VTE

BACKGROUND

Venous thromboembolism (VTE) is a collective term for two conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE). A proportion of people with VTE have no underlying or immediately predisposing risk factors and the VTE is referred to as unprovoked. Unprovoked VTE can often be the first clinical manifestation of an underlying malignancy. This has raised the question of whether people with an unprovoked VTE should be investigated for an underlying cancer. Treatment for VTE is different in cancer and non-cancer patients and a correct diagnosis would ensure that people received the optimal treatment for VTE to prevent recurrence and further morbidity. Furthermore, an appropriate cancer diagnosis at an earlier stage could avoid the risk of cancer progression and lead to improvements in cancer-related mortality and morbidity. This is the third update of the review first published in 2015.

OBJECTIVES

To determine whether testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT of the lower limb or PE) is effective in reducing cancer- or VTE-related mortality and morbidity and to determine which tests for cancer are best at identifying treatable cancers early.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 5 May 2021. We also undertook reference checking to identify additional studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials in which people with an unprovoked VTE were allocated to receive specific tests for identifying cancer or clinically indicated tests only were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias and extracted data. We assessed the certainty of the evidence using GRADE criteria. We resolved any disagreements by discussion. The main outcomes of interest were all-cause mortality, cancer-related mortality and VTE-related mortality.

MAIN RESULTS

No new studies were identified for this 2021 update. In total, four studies with 1644 participants are included. Two studies assessed the effect of extensive tests including computed tomography (CT) scanning versus tests at the physician's discretion, while the other two studies assessed the effect of standard testing plus positron emission tomography (PET)/CT scanning versus standard testing alone. For extensive tests including CT versus tests at the physician's discretion, the certainty of the evidence, as assessed according to GRADE, was low due to risk of bias (early termination of the studies). When comparing standard testing plus PET/CT scanning versus standard testing alone, the certainty of evidence was moderate due to a risk of detection bias. The certainty of the evidence was downgraded further as detection bias was present in one study with a low number of events. When comparing extensive tests including CT versus tests at the physician's discretion, pooled analysis on two studies showed that testing for cancer was consistent with either benefit or no benefit on cancer-related mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.15 to 1.67; 396 participants; 2 studies; low-certainty evidence). One study (201 participants) showed that, overall, malignancies were less advanced at diagnosis in extensively tested participants than in participants in the control group. In total, 9/13 participants diagnosed with cancer in the extensively tested group had a T1 or T2 stage malignancy compared to 2/10 participants diagnosed with cancer in the control group (OR 5.00, 95% CI 1.05 to 23.76; low-certainty evidence). There was no clear difference in detection of advanced stages between extensive tests versus tests at the physician's discretion: one participant in the extensively tested group had stage T3 compared with four participants in the control group (OR 0.25, 95% CI 0.03 to 2.28; low-certainty evidence). In addition, extensively tested participants were diagnosed earlier than control group (mean: 1 month with extensive tests versus 11.6 months with tests at physician's discretion to cancer diagnosis from the time of diagnosis of VTE). Extensive testing did not increase the frequency of an underlying cancer diagnosis (OR 1.32, 95% CI 0.59 to 2.93; 396 participants; 2 studies; low-certainty evidence). Neither study measured all-cause mortality, VTE-related morbidity and mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life. When comparing standard testing plus PET/CT screening versus standard testing alone, standard testing plus PET/CT screening was consistent with either benefit or no benefit on all-cause mortality (OR 1.22, 95% CI 0.49 to 3.04; 1248 participants; 2 studies; moderate-certainty evidence), cancer-related mortality (OR 0.55, 95% CI 0.20 to 1.52; 1248 participants; 2 studies; moderate-certainty evidence) or VTE-related morbidity (OR 1.02, 95% CI 0.48 to 2.17; 854 participants; 1 study; moderate-certainty evidence). Regarding stage of cancer, there was no clear difference for detection of early (OR 1.78, 95% 0.51 to 6.17; 394 participants; 1 study; low-certainty evidence) or advanced (OR 1.00, 95% CI 0.14 to 7.17; 394 participants; 1 study; low-certainty evidence) stages of cancer. There was also no clear difference in the frequency of an underlying cancer diagnosis (OR 1.71, 95% CI 0.91 to 3.20; 1248 participants; 2 studies; moderate-certainty evidence). Time to cancer diagnosis was 4.2 months in the standard testing group and 4.0 months in the standard testing plus PET/CT group (P = 0.88). Neither study measured VTE-related mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life.

AUTHORS' CONCLUSIONS

Specific testing for cancer in people with unprovoked VTE may lead to earlier diagnosis of cancer at an earlier stage of the disease. However, there is currently insufficient evidence to draw definitive conclusions concerning the effectiveness of testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT or PE) in reducing cancer- or VTE-related morbidity and mortality. The results could be consistent with either benefit or no benefit. Further good-quality large-scale randomised controlled trials are required before firm conclusions can be made.

Prothrombotic genotypes and risk of venous thromboembolism in occult cancer

BACKGROUND

Studies have reported that the combination of some prothrombotic genotypes and overt cancer yields a synergistic effect on VTE risk. Whether individual prothrombotic genotypes or number of risk alleles in a genetic risk score (GRS) affect VTE risk in occult cancer have not been addressed. The aim of this study was to investigate the joint effect of five prothrombotic genotypes and occult cancer on VTE risk.

METHODS

Cases with incident VTE (n = 1566) and a subcohort (n = 14,537) were sampled from the Scandinavian Thrombosis and Cancer Cohort (1993-2012). Five single nucleotide polymorphisms previously reported in a GRS were genotyped: ABO (rs8176719), F5 (rs6025), F2 (rs1799963), FGG (rs2066865) and F11 (rs2036914). Hazard ratios (HRs) for VTE by individual SNPs and GRS were estimated according to non-cancer and occult cancer (one year preceding a cancer diagnosis) exposure.

RESULTS

Occult cancer occurred in 1817 subjects, and of these, 93 experienced a VTE. The VTE risk was 4-fold higher (HR 4.05, 95% CI 3.28-5.00) in subjects with occult cancer compared with those without cancer. Among subjects with occult cancer, those with VTE had a higher proportion of prothrombotic and advanced cancers than those without VTE. The VTE risk increased according to individual prothrombotic genotypes and GRS in cancer-free subjects, while no such effect was observed in subjects with occult cancer (HR for ≥4 versus ≤1 risk alleles in GRS: 1.14, 95% CI 0.61-2.11).

CONCLUSIONS

Five well-established prothrombotic genotypes, individually or combined, were not associated with increased risk of VTE in individuals with occult cancer.

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.

Risk scores for occult cancer in patients with unprovoked venous thromboembolism: Results from an individual patient data meta-analysis

BACKGROUND

The Registro Informatizado de Pacientes con Enfermedad TromboEmbólica (RIETE) score and the Screening for Occult Malignancy in Patients with Idiopathic Venous Thromboembolism (SOME) risk scores aim to identify patients with acute unprovoked venous thromboembolism (VTE) at high risk of occult cancer, but their predictive performance is unclear.

METHODS

The scores were evaluated in an individual patient data meta-analysis. Studies were eligible if enrolling consecutive adults with unprovoked VTE who underwent protocol-mandated screening for cancer. The primary outcome was a cancer diagnosis between 30 days and 2 years of follow-up. The discriminatory performance was evaluated by computing the area under the receiver (ROC) curve in random-effects meta-analyses.

RESULTS

The RIETE score could be calculated in 1753 patients, of whom 63 (3.6%) were diagnosed with cancer. The pooled area under the ROC curve was 0.59 (95% confidence interval [CI], 0.52-0.66; I2  = 0%). Of the 427 patients (24%) classified as high risk, 25 (5.9%) were diagnosed with cancer compared with 38 of 1326 (2.9%) low-risk patients (hazard ratio [HR], 2.0; 95% CI, 1.3-3.4). The SOME score was calculated in 925 patients, of whom 37 (4.0%) were diagnosed with cancer. The pooled area under the ROC curve was 0.56 (95% CI, 0.46-0.65; I2  = 46%). Of the 161 patients (17%) classified as high risk (≥2 points), eight (5.0%) were diagnosed with cancer compared with 29 of 764 (3.8%) low-risk patients (HR, 1.2; 95% CI, 0.55-2.7).

CONCLUSIONS

The predictive discriminatory performance of both scores is poor. When used dichotomously, the RIETE score is able to discriminate between low- and high-risk patients. Because this is largely driven by advanced age, these results do not support the use of these scores in daily clinical practice.

Performance of 18F-fluorodesoxyglucose positron-emission tomography/computed tomography for cancer screening in patients with unprovoked venous thromboembolism: Results from an individual patient data meta-analysis

INTRODUCTION

Venous thromboembolism (VTE) may be the first manifestation of cancer. We aimed at evaluating the performance of ¹⁸F-Fluorodesoxyglucose Positron-Emission Tomography/Computed Tomography (FDG PET/CT) for occult cancer screening in patients with unprovoked VTE.

METHODS

This was a pre-specified analysis of a systematic review and individual patient data meta-analysis including prospective studies assessing cancer screening in patients with unprovoked VTE. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FDG PET/CT were calculated based on cancer diagnosis during a 1-year follow-up period.

RESULTS

Four studies were identified as using FDG PET/CT as part of their extensive screening strategy. Out of the 332 patients who underwent FDG PET/CT, the scan was interpreted as positive in 67 (20.2%), as equivocal in 27 (8.1%), and as negative in 238 (71.7%). Seventeen (5.1%) patients were diagnosed with cancer at inclusion or during the 12-month follow up period. All cancers were diagnosed at initial screening. Pooled sensitivity, specificity, NPV, and PPV were 87.3% (95% CI, 55.3 to 97.4), 70.2% (95% CI, 48.2 to 85.6), 98.9% (95% CI, 94.3 to 99.7), and 17.9% (95% CI, 8.5 to 33.6), respectively.

CONCLUSION

FDG PET/CT appears to have satisfactory accuracy indices for cancer diagnosis in patients with unprovoked VTE. In particular, it exhibits a very high negative predictive value and could be used to rule out the presence of an underlying occult malignancy in this setting.

Unprovoked venous thromboembolism in women over 40: is screening for occult malignancy with mammography and abdominopelvic CT of benefit?

AIM

To determine imaging and pathological outcomes in cases of unprovoked venous thromboembolism (VTE) referred for mammogram. A secondary objective was to elucidate outcomes of abdominopelvic computed tomography (CT) imaging performed in this cohort.

MATERIALS AND METHODS

A retrospective review of mammograms performed in cases of unprovoked VTE was undertaken from January 2016 to September 2019. Patient notes and imaging were reviewed to establish patient demographics, additional imaging required, biopsies performed, pathology findings, and eventual outcomes. Cases were reviewed to determine if concurrent CT abdomen/pelvis was performed to screen for malignancy. Outcomes of CT were recorded.

RESULTS

One hundred and thirty-nine women attended for screening mammogram following unprovoked VTE during the study period. Mean patient age was 68 years (range 42-89 years). Fourteen women (10%) were recalled for further breast imaging, with two cases of confirmed malignancy (1.4%). Of the 139 women, 118 also underwent CT imaging, with 18 patients (15%) recalled for further investigations. Two (1.7%) cases of malignancy (lung and ovarian) were identified.

CONCLUSION

A low cancer detection rate was demonstrated in women undergoing mammography or CT following unprovoked VTE. In addition, the high number of false-positive findings and need for additional investigations questions the value of screening in this setting. Based on these findings, Cambridge Breast Unit has ceased mammographic and abdominopelvic CT imaging in women with unprovoked VTE, anticipating the newly updated National Institute for Health and Care Excellence (NICE) guidelines.

Cancer Screening in Patients with Unprovoked Thromboembolism: How to do it and Who Benefits?

Introduction: Unprovoked venous thromboembolism (uVTE) may be the first manifestation of cancer. The main objectives of this study were to compare limited screening (LS) and extended screening (ES) and to make a protocol to approach these patients.

Methods: This is a retrospective, unicentric observational study that included 245 patients with venous thromboembolism (VTE) admitted to an Internal Medicine Service for five years. The incidence of cancer and mortality during hospitalization, and at one and three years after admission were calculated in both LS and ES groups and compared.

Results: Of the 245 patients with VTE, 59 (24.1%) had uVTE: 35 (59.3%) were submitted to LS and 24 (40.7%) to ES, with 10 (4.1%) diagnosis of cancer. In the following three years, 10 more patients were diagnosed. There were no statistically significant differences in inpatient diagnosis rates (8.6% vs. 4.2%; p=0.51) or in-hospital mortality (2.9% vs. 4.2%; p=0.79) or mortality at one year (8.6% vs. 8.3%; p=0.97) and three years (20.0% vs. 20.8%; p = 0.94) between LS and ES groups respectively. The Computerized Registry of Patients with Venous Thromboembolism (RIETE) score was equal or superior to 3 in 69.5% (N=41) of the population with uVTE.

Discussion: The results of our study are consistent with the literature; there are no differences between screenings, as the difference in the number of diagnoses does not reflect on mortality.

Conclusion: There were no statistically significant differences between the two types of screening in this population. We suggest a protocol that includes the RIETE score to better select the patients who might benefit the most from an ES.

A clinical practice-based evaluation of the RIETE score in predicting occult cancer in patients with venous thromboembolism

The association between venous thromboembolism (VTE) and occult cancer is well established. However, the benefit of cancer screening in all VTE patients remains controversial. The Registro Informatizado Enfermedad TromboEmbólica (RIETE) score is a recently proposed risk score to identify VTE patients at high risk of occult cancer. We evaluated the performance of the RIETE score in a routine clinical setting comprising patients presenting with VTE between January 1 and December 31, 2014, at Danderyd University hospital. Out of 488 VTE patients, 47 (9.6%) patients received a new cancer diagnosis during a 24-month follow-up. After exclusion of patients with cancer diagnosed at baseline (≤ 10 days after VTE, n = 16), 472 patients were considered eligible for cancer screening. Among these 472 patients, 31 (6.6%) received a cancer diagnosis during follow-up. The cumulative incidence was high after both unprovoked (8.5%) and provoked (4.8%) VTE. The RIETE score was evaluated in 467 of these patients. Interestingly, a high RIETE score was not significantly associated with cancer diagnosis during follow-up (OR 1.78; 95% CI 0.85-3.63), which was mainly due to a poor performance in women (OR 1.04; 95% CI 0.30-2.83). In summary, we observed a relatively high incidence of occult cancer in both unprovoked and provoked VTE. The RIETE score performed poorly in identifying patients at high risk of occult cancer in our VTE population. Additional risk assessment models are warranted to identify VTE patients who would benefit from extensive cancer screening.

Increased risk for cancer after stroke at a young age: etiological relevance or incidental finding?

BACKGROUND

Etiological factors, such as a malignant disease, in young stroke patients are often neglected. Therefore, in this study, we aimed to investigate the risk of developing cancer in young stroke survivors.

METHODS

The current case-control study sample included patients who received an initial ischemic stroke diagnosis documented in the Disease Analyzer database (IQVIA), which compiles data such as risk factors, drug prescriptions, and diagnoses obtained from general practitioners and specialists.

RESULTS

The stroke and non-stroke groups included 18,668 patients each; each group had 2836 (15.3%) participants ≤ 55 years. The cancer incidence in the stroke group over the age of 55 years was higher than in the younger subgroup (29.4% versus 17.3%). The proportions of cancer patients within 10 years of follow-up were higher in the stroke group versus the non-stroke group, as well as in the subgroup of patients aged ≤ 55 versus patients > 55 years (17.3% versus 9.5% and 29.4% versus 24.9%, respectively). The calculated hazard ratio for developing cancer within 10 years of follow-up was higher in the younger stroke population (≤ 55 years) than in the older population (hazard ratio: 1.47 (CI 1.18-1.83) versus 1.17 (CI 1.10-1.25).

CONCLUSION

In our cohort, young individuals aged ≤ 55 years who suffered a stroke had twice as high risk for developing cancer within 10 years after the index event compared to the control group. Stroke might have implication regarding the subsequent development of cancer and vice versa.

Cancer-associated thrombosis: the when, how and why

Cancer-associated thrombosis (CAT) is a condition in which relevance has been increasingly recognised both for physicians that deal with venous thromboembolism (VTE) and for oncologists. It is currently estimated that the annual incidence of VTE in patients with cancer is 0.5% compared to 0.1% in the general population. Active cancer accounts for 20% of the overall incidence of VTE. Of note, VTE is the second most prevalent cause of death in cancer, second only to the progression of the disease, and cancer is the most prevalent cause of deaths in VTE patients. Nevertheless, CAT presents several peculiarities that distinguish it from other VTE, both in pathophysiology mechanisms, risk factors and especially in treatment, which need to be considered. CAT data will be reviewed in this review.

Cancer-associated thrombosis (CAT) presents peculiar features (risk factors and pathophysiology) that distinguish it from common VTE cases. Treatment of CAT requires a different approach, since the patients are more prone to recurrence and bleeding.http://ow.ly/j1Lu30nYmd5

Effect of testing for cancer on cancer- or venous thromboembolism (VTE)-related mortality and morbidity in people with unprovoked VTE

BACKGROUND

Venous thromboembolism (VTE) is a collective term for two conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE). A proportion of people with VTE have no underlying or immediately predisposing risk factors and the VTE is referred to as unprovoked. Unprovoked VTE can often be the first clinical manifestation of an underlying malignancy. This has raised the question of whether people with an unprovoked VTE should be investigated for an underlying cancer. Treatment for VTE is different in cancer and non-cancer patients and a correct diagnosis would ensure that people received the optimal treatment for VTE to prevent recurrence and further morbidity. Furthermore, an appropriate cancer diagnosis at an earlier stage could avoid the risk of cancer progression and lead to improvements in cancer-related mortality and morbidity. This is an update of a review first published in 2015.

OBJECTIVES

To determine whether testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT of the lower limb or PE) is effective in reducing cancer or VTE-related mortality and morbidity and to determine which tests for cancer are best at identifying treatable cancers early.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 11 July 2018. We also undertook reference checking to identify additional studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials in which people with an unprovoked VTE were allocated to receive specific tests for identifying cancer or clinically indicated tests only were eligible for inclusion. Primary outcomes included all-cause mortality, cancer-related mortality and VTE-related mortality.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias and extracted data. We resolved any disagreements by discussion.

MAIN RESULTS

No new studies were identified for this 2018 update. In total, four studies with 1644 participants are included. Two studies assessed the effect of extensive tests including computed tomography (CT) scanning versus tests at the physician's discretion, while the other two studies assessed the effect of standard testing plus positron emission tomography (PET)/CT scanning versus standard testing alone. For extensive tests including CT versus tests at the physician's discretion, the quality of the evidence, as assessed according to GRADE, was low due to risk of bias (early termination of the studies). When comparing standard testing plus PET/CT scanning versus standard testing alone, the quality of evidence was moderate due to a risk of detection bias. The quality of the evidence was downgraded further as detection bias was present in one study with a low number of events.When comparing extensive tests including CT versus tests at the physician's discretion, pooled analysis on two studies showed that testing for cancer was consistent with either benefit or no benefit on cancer-related mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.15 to 1.67; 396 participants; 2 studies; P = 0.26; low-quality evidence). One study (201 participants) showed that, overall, malignancies were less advanced at diagnosis in extensively tested participants than in participants in the control group. In total, 9/13 participants diagnosed with cancer in the extensively tested group had a T1 or T2 stage malignancy compared to 2/10 participants diagnosed with cancer in the control group (OR 5.00, 95% CI 1.05 to 23.76; P = 0.04; low-quality evidence). There was no clear difference in detection of advanced stages between extensive tests versus tests at the physician's discretion: one participant in the extensively tested group had stage T3 compared with four participants in the control group (OR 0.25, 95% CI 0.03 to 2.28; P = 0.22; low-quality evidence). In addition, extensively tested participants were diagnosed earlier than control group (mean: 1 month with extensive tests versus 11.6 months with tests at physician's discretion to cancer diagnosis from the time of diagnosis of VTE). Extensive testing did not increase the frequency of an underlying cancer diagnosis (OR 1.32, 95% CI 0.59 to 2.93; 396 participants; 2 studies; P = 0.50; low-quality evidence). Neither study measured all-cause mortality, VTE-related morbidity and mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life.When comparing standard testing plus PET/CT screening versus standard testing alone, standard testing plus PET/CT screening was consistent with either benefit or no benefit on all-cause mortality (OR 1.22, 95% CI 0.49 to 3.04; 1248 participants; 2 studies; P = 0.66; moderate-quality evidence), cancer-related mortality (OR 0.55, 95% CI 0.20 to 1.52; 1248 participants; 2 studies; P = 0.25; moderate-quality evidence) or VTE-related morbidity (OR 1.02, 95% CI 0.48 to 2.17; 854 participants; 1 study; P = 0.96; moderate-quality evidence). Regarding stage of cancer, there was no clear difference for detection of early (OR 1.78, 95% 0.51 to 6.17; 394 participants; 1 study; P = 0.37; low-quality evidence) or advanced (OR 1.00, 95% CI 0.14 to 7.17; 394 participants; 1 study; P = 1.00; low-quality evidence) stages of cancer. There was also no clear difference in the frequency of an underlying cancer diagnosis (OR 1.71, 95% CI 0.91 to 3.20; 1248 participants; 2 studies; P = 0.09; moderate-quality evidence). Time to cancer diagnosis was 4.2 months in the standard testing group and 4.0 months in the standard testing plus PET/CT group (P = 0.88). Neither study measured VTE-related mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life.

AUTHORS' CONCLUSIONS

Specific testing for cancer in people with unprovoked VTE may lead to earlier diagnosis of cancer at an earlier stage of the disease. However, there is currently insufficient evidence to draw definitive conclusions concerning the effectiveness of testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT or PE) in reducing cancer- or VTE-related morbidity and mortality. The results could be consistent with either benefit or no benefit. Further good-quality large-scale randomised controlled trials are required before firm conclusions can be made.

Revisiting occult cancer screening in patients with unprovoked venous thromboembolism

Unprovoked venous thromboembolism (VTE) can be the first manifestation of an unknown cancer. A recently published individual patient data meta-analysis (IPDMA) reported a prevalence of occult cancer detection of 5.2% (95% CI, 4.1% to 6.5%) over a one-year follow-up period, approximately 50% lower than the previously reported 12-month period prevalence. Although an extensive screening strategy was associated with a 2-fold higher probability of cancer detection at initial screening in the IPDMA, not enough evidence exists yet to support the routine use of these tests in patients with unprovoked VTE. It is likely that a subgroup of patients with unprovoked VTE is at higher risk of occult cancer detection and might benefit from closer clinical surveillance. A newly derived and validated clinical predictive rule seems to be able to stratify patients with unprovoked VTE accordingly to their underlying risk of occult cancer detection. The low incidence of occult cancer detection (<3%) in the low-risk group is reassuring for clinicians. Future studies are required to better define the risks and benefits of an extensive occult cancer screening strategy in high risk patients sub-group with unprovoked VTE. To date, the Scientific and Standardized Committee from the International Society of Thrombosis and Haemostasis suggests that patients with unprovoked VTE should only undergo a limited cancer screening including thorough medical history and physical examination, basic laboratory investigations, chest X-ray as well as age- and gender-specific cancer screening according to national guidelines.

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Zusammenfassung. Eine unprovozierte venöse Thromboembolie (VTE) kann das erste Zeichen einer Neoplasie sein. Bei 5–10 % der Patienten wird in den nachfolgenden zwölf Monaten eine Krebserkrankung diagnostiziert. Bei allen Patienten nach einer unprovozierten VTE sollte deshalb eine gründliche Anamnese, eine sorgfältige klinische Untersuchung, eine Blutanalyse (Blutbild mit Blutausstrich, Leberenzyme, Kalzium), der Urinstatus und ein Thorax-Röntgen durchgeführt werden. Zusätzlich sollten ergänzend, je nach Alter und Geschlecht, die spezifischen Vorsorgeuntersuchungen (Darm, Zervix, Mamma und Prostata) vorgenommen werden. Alle auffälligen Befunde sollten weiter abgeklärt werden. Für eine noch aggressivere Tumorsuche konnte bislang kein Vorteil in Hinsicht auf die Tumordetektionsrate oder auf die Senkung der krebsbedingten Mortalität gezeigt werden.

Controversies in venous thromboembolism: to treat or not to treat superficial vein thrombosis

The management of superficial vein thrombosis (SVT) is poorly defined and remains controversial overall. SVT has long been considered a benign, self-limited disease, but recent studies show that SVT carries a nonnegligible risk for recurrence, deep vein thrombosis, or pulmonary embolism. Current guidelines recommend the use of low-molecular-weight heparin or fondaparinux, but results of several surveys indicate that the majority of patients with SVT receive nonanticoagulant therapy only, which includes compression stockings or bandages, nonsteroidal anti-inflammatory drugs, topical application of heparin gel, or surgical interventions. However, several recent observational and interventional studies provide better insight into the optimal treatment of patients with SVT who are at different risks for thromboembolic complications. This educational review summarizes the available evidence and aims to provide practical guidance based on a clinical decision pathway.

Effect of testing for cancer on cancer- and venous thromboembolism (VTE)-related mortality and morbidity in people with unprovoked VTE

BACKGROUND

Venous thromboembolism (VTE) is a collective term for two conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE). A proportion of people with VTE have no underlying or immediately predisposing risk factors and the VTE is referred to as unprovoked. Unprovoked VTE can often be the first clinical manifestation of an underlying malignancy. This has raised the question of whether people with an unprovoked VTE should be investigated for an underlying cancer. Treatment for VTE is different in cancer and non-cancer patients and a correct diagnosis would ensure that people received the optimal treatment for VTE to prevent recurrence and further morbidity. Furthermore, an appropriate cancer diagnosis at an earlier, potentially curative stage could avoid the risk of cancer progression and thus lead to improvements in cancer-related mortality and morbidity. This is an update of a review first published in 2015.

OBJECTIVES

To determine whether testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT of the lower limb or PE) is effective in reducing cancer and VTE-related mortality and morbidity and to determine which tests for cancer are best at identifying treatable cancers early.

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (16 February 2017). In addition, the CIS searched the Cochrane Register of Studies CENTRAL (2017, Issue 1). We searched trials registries (February 2017) and checked the reference lists of relevant articles.

SELECTION CRITERIA

Randomised and quasi-randomised trials in which people with an unprovoked VTE were allocated to receive specific tests for cancer or clinically indicated tests only were eligible for inclusion in this review. Primary outcomes included all-cause mortality, cancer-related mortality and VTE-related mortality.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed quality and extracted data. We resolved any disagreements by discussion.

MAIN RESULTS

Four studies with 1644 participants met the inclusion criteria (two studies in the original review and two in this update). Two studies assessed the effect of extensive tests versus tests at the physician's discretion) while the other two studies assessed the effect of standard testing plus positron emission tomography (PET)/computed tomography (CT) scanning versus standard testing alone. For extensive tests versus tests at the physician's discretion, the quality of the evidence was low due to risk of bias (early termination of the studies). When comparing standard testing plus PET/CT scanning versus standard testing alone, the quality of evidence was moderate due to a risk of detection bias. The quality of the evidence was downgraded further when detection bias was present in one study with a low number of events.When comparing extensive tests versus tests at the physician's discretion, pooled analysis on two studies showed that testing for cancer was consistent with either a benefit or no benefit on cancer-related mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.15 to 1.67; 396 participants; 2 studies; P = 0.26; low quality evidence). One study (201 participants) showed that, overall, malignancies were less advanced in extensively tested participants than in participants in the control group. In total, 9/13 participants diagnosed with cancer in the extensively tested group had a T1 or T2 stage malignancy compared to 2/10 participants diagnosed with cancer in the control group (OR 5.00, 95% CI 1.05 to 23.76; P = 0.04; low quality evidence). There was no clear difference in detection of advanced stages between extensive tests versus tests at the physician's discretion: one participant in the extensively tested group had stage T3 compared with four participants in the control group (OR 0.25, 95% CI 0.03 to 2.28; P = 0.22; low quality evidence). In addition, extensively tested participants were diagnosed earlier than control group (mean: 1 month with extensive tests versus 11.6 months with tests at physician's discretion to cancer diagnosis from the time of diagnosis of VTE). Extensive testing did not increase the frequency of an underlying cancer diagnosis (OR 1.32, 95% CI 0.59 to 2.93; 396 participants; 2 studies; P = 0.50; low quality evidence). Neither study measured all-cause mortality, VTE-related morbidity and mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life.When comparing standard testing plus PET/CT screening versus standard testing alone, standard testing plus PET/CT screening was consistent with either a benefit or no benefit on all-cause mortality (OR 1.22, 95% CI 0.49 to 3.04; 1248 participants; 2 studies; P = 0.66; moderate quality evidence), cancer-related mortality (OR 0.55, 95% CI 0.20 to 1.52; 1248 participants; 2 studies; P = 0.25; moderate quality evidence) or VTE-related morbidity (OR 1.02, 95% CI 0.48 to 2.17; 854 participants; 1 study; P = 0.96; moderate quality evidence). With regards to stage of cancer, there was no clear difference for detection of early (OR 1.78, 95% 0.51 to 6.17; 394 participants; 1 study; P = 0.37; low quality evidence) or advanced (OR 1.00, 95% CI 0.14 to 7.17; 394 participants; 1 study; P = 1.00; low quality evidence) stages of cancer. There was also no clear difference in the frequency of an underlying cancer diagnosis (OR 1.71, 95% CI 0.91 to 3.20; 1248 participants; 2 studies; P = 0.09; moderate quality evidence). Time to cancer diagnosis was 4.2 months in the standard testing group and 4.0 months in the standard testing plus PET/CT group (P = 0.88). Neither study measured VTE-related mortality, complications of anticoagulation, adverse effects of cancer tests, participant satisfaction or quality of life.

AUTHORS' CONCLUSIONS

Testing for cancer in people with unprovoked VTE may lead to earlier diagnosis of cancer at an earlier stage of the disease. However, there is currently insufficient evidence to draw definitive conclusions concerning the effectiveness of testing for undiagnosed cancer in people with a first episode of unprovoked VTE (DVT or PE) in reducing cancer and VTE-related morbidity and mortality. The results could be consistent with either benefit or no benefit. Further good-quality large-scale randomised controlled trials are required before firm conclusions can be made.

Epidemiological and outcome data in Japanese patients with deep vein thrombosis with and without malignancy

There are very few epidemiological studies on Japanese patients with deep vein thrombosis (DVT). In particular, mortality rate differences in Japanese DVT patients with and without malignancy have rarely been evaluated. To elucidate these differences, we enrolled 211 patients who had been diagnosed with de-novo acute DVT of the pelvis or lower extremities between January 2012 and December 2015. The clinical characteristics, treatment information, and follow-up data were retrospectively assessed. We compared these variables in patients with (n = 120) and without (n = 91) concomitant malignancies. The median age of patients was 67 years, 33.7% were male, and 82.9% patients were treated with oral anticoagulants including direct oral anticoagulants. The clinical characteristics and treatment provided were almost identical in the two groups with some exceptions. Three-year survival rates of the total population, patients with malignancy, and patients without malignancy were 80.6, 67.6, and 97.6%, respectively (log-rank p < 0.001). Multivariable Cox regression analysis demonstrated that malignancy was independently associated with high risk of 3-year all-cause mortality with an adjusted hazard ratio of 9.1 (95% confidence interval; 2.1-39.0, p = 0.003). Bootstrap validation demonstrated an acceptable index corrected slope of 0.766 without significant overfitting in a multivariable model. In conclusion, we analyzed epidemiological data on Japanese patients with DVT. Malignancy was independently associated with increased 3-year all-cause mortality.

Risk of cancer after anticoagulation in patients with unprovoked venous thromboembolism: an observational cohort study

Essentials Data on long-term cancer risk are controversial in patients with venous thromboembolism (VTE). We assessed long-term rates and risk factors of cancer in patients with VTE. Cancer risk after anticoagulation is not higher in VTE patients than in the general population. VTE recurrence is not predictive of a future cancer diagnosis.

SUMMARY

Background Patients with venous thromboembolism (VTE) are at risk of having a subsequent cancer diagnosis. The risk is highest during the first 6 months. Reports on cancer rates thereafter are controversial. We aimed to assess long-term rates and risk factors of cancer in patients with VTE. Methods and Results We followed patients with a first unprovoked VTE after discontinuation of anticoagulation, and excluded those receiving long-term antithrombotic therapy or with major thrombophilia. The study endpoint was the occurrence of cancer. Sixty-two (5.2%) of 1188 patients developed cancer during a median follow-up of 98 months. The cumulative incidence rates of cancer were 0.7% (95% confidence interval [CI] 0.2-1.2%), 3.1% (95% CI 2.0-4.1%) and 9% (95% CI 6.5-11.5) after 1, 5 and 15 years; these were not significantly different from those in the matched general population (0.6%, 3.4%, and 12.2%, respectively). The corresponding standardized incidence ratios (ratio of the observed cancer cases and the number of cases based on national cancer incidence rates) of 1.1 (95% CI 0.5-2.5), 1.0 (95% CI 0.6-1.4) and 0.9 (95% CI 0.7-1.2) did not indicate a difference in cancer incidence between our cohort and the general population. Advancing age (hazard ratio [HR] per decade 1.5, 95% CI 1.2-2.0) and shorter duration of anticoagulation (HR per 1-month decrease 1.3, 95% CI 1.1-1.6) were associated with an increased cancer risk, whereas VTE recurrence was not (HR 1.17, 95% CI 0.66-2.07). Conclusions Asymptomatic patients with unprovoked VTE who have completed anticoagulation therapy do not have a higher cancer risk. The inverse association between the duration of anticoagulation and the incidence of cancer warrants further investigation.

Occult cancer detection in venous thromboembolism: the past, the present, and the future

Unprovoked venous thromboembolism (VTE) can be the first manifestation of an undiagnosed cancer. Recently published studies have suggested that approximately 4-5% of patients with new unprovoked VTE will be diagnosed with cancer within 12 months of follow-up. Therefore, it is important for clinicians to keep a low threshold of suspicion for occult cancer in this patient population. After an unprovoked VTE diagnosis, patients should undergo a thorough medical history, physical examination, basic laboratory investigations (ie, complete blood count and liver function tests), chest X-ray, as well as age- and gender-specific cancer screening (breast, cervical, colon, and prostate). More intensive cancer screening including additional investigations (eg, computed tomography of the abdomen/pelvis) does not seem to increase the rate of occult cancer detection, decrease cancer-related morbidity, or increase survival or cost-effectiveness.

Screening for cancer in patients with unprovoked venous thromboembolism: protocol for a systematic review and individual patient data meta-analysis

INTRODUCTION

Occult cancer is present in 4%-9% of patients with unprovoked venous thromboembolism (VTE). Screening for cancer may be considered in these patients, with the aim to diagnose cancers in an early, potentially curable stage. Information is needed about the risk of occult cancer, overall and in specific subgroups, additional risk factors and on the performance of different screening strategies.

METHODS AND ANALYSIS

MEDLINE, Embase and CENTRAL databases were searched from November 2007 to January 2016 for prospective studies that had evaluated protocol-mandated screening for cancer in patients with unprovoked VTE and with at least 12 months' follow-up. Two reviewers independently assessed articles for eligibility. Ten eligible studies were identified and individual patient data were obtained from each of them. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool . Generalised linear mixed-effects models was used to calculate estimates in a one-stage meta-analytic approach, overall and in a number of subgroups, including patients undergoing limited screening only, elderly patients, patients with previous VTE, smokers and patients using oestrogens.

ETHICS AND DISSEMINATION

Ethical approval is not required for this systematic review and individual patient data meta-analysis. Findings have been submitted for publication in peer-reviewed journals and presentations at national and international conferences to provide clinicians and other decision-makers with valid and precise risk estimates of occult cancer, overall and in specific clinical subgroups, with risk factors for occult cancer, with estimates of the diagnostic performance of limited screening and with an exploration of the benefit of extensive screening strategies.

Occult cancer detection in patients with hemostatic disorder and venous thromboembolism

There are physiologic ties between Von Willebrand Factor (VWF) and circulating tumor cells. VWF appears to play a role in tumor biology, but it is unclear whether cancer behavior differs in Von Willebrand Disease. In patients presenting with venous thromboembolism (VTE), occult cancer is frequently considered as an underlying cause. The prevalence of occult cancer after provoked VTE is low (3%); therefore, cancer screening in these patients is not routinely recommended. In those with unprovoked VTE, occult cancer is more prevalent, estimated between 4 and 10%. Due to this elevated risk, occult cancer screening is recommended in this population. Multiple studies have investigated whether a "limited" approach (including history and physical exam, basic labs, and chest X-ray) versus "extensive" approach (addition of advanced imaging, such as computer tomography) is more effective. Current data fails to demonstrate extensive screening strategies diagnose more occult cancer, miss fewer cancers during follow up, or improve cancer-related mortality. Furthermore, many patients may be needlessly exposed to unnecessary diagnostic procedures with their associated complications and costs, as well as significant anxiety. Therefore, the decision to perform additional testing should be made on a case-by-case basis. Additional studies are needed to identify subgroups of patients with unprovoked VTE at highest risk for occult cancer.