Learning objectives and key messages
- About 20% of all venous thromboembolism (VTE) occurs in cancer patients, and up to 20% of cancer patients develop VTE before death [1]; thrombosis is the second leading cause of death in cancer patients after disease progression [2].
- The Khorana score is the main tool for selecting outpatients for prophylaxis; in a meta-analysis, 6-month VTE incidence with scores of 0, 1 to 2 and 3 or more was 5.0%, 6.6% and 11.0% respectively, but most events occurred outside the high-risk group [3].
- In an outpatient with Khorana ≥2 and low bleeding risk, prophylactic-dose apixaban or rivaroxaban is an option; apixaban in AVERT reduced VTE from 10.2% to 4.2% but increased major bleeding [2, 4].
- For treatment of VTE, low-molecular-weight heparin (LMWH) or a direct oral anticoagulant (apixaban, rivaroxaban or edoxaban) is recommended for at least 6 months; in gastrointestinal cancers, especially upper GI, edoxaban and rivaroxaban have caused more GI bleeding [2, 5].
- In Caravaggio, apixaban was non-inferior to dalteparin and did not cause more major bleeding (3.8% vs 4.0%) [6].
- After 6 months, continuing anticoagulation is preferred in active cancer; in API-CAT, reduced-dose apixaban (2.5 mg twice a day) was non-inferior to full dose and caused less clinically relevant bleeding [1, 7].
Risk assessment: the Khorana score
The risk of VTE is higher in patients who are hospitalised, on systemic treatment or with metastatic disease. Surgery, chemotherapy, hormone therapy and some targeted drugs (such as thalidomide and lenalidomide) increase the risk, and pancreatic, kidney, ovarian, lung and stomach cancers have the highest VTE rates; red cell transfusion and erythropoiesis-stimulating agents also raise the risk [1]. Outpatients should be stratified as low, intermediate or high risk using a validated tool such as the Khorana score together with clinical judgement [1].
| Patient characteristic (before chemotherapy) | Score |
|---|---|
| Very high-risk cancer site: stomach, pancreas | 2 |
| High-risk cancer site: lung, lymphoma, gynaecological, bladder, testicular | 1 |
| Platelets 350,000/µL or more | 1 |
| Haemoglobin below 10 g/dL or use of an erythropoiesis-stimulating agent | 1 |
| White cell count above 11,000/µL | 1 |
| Body mass index 35 kg/m² or more | 1 |
In the original study (derivation and validation cohorts), VTE incidence over about 2.5 months was 0.8% and 0.3% with a score of 0, 1.8% and 2% with a score of 1 to 2, and 7.1% and 6.7% with a score of 3 or more [8]. In a meta-analysis of 34,555 patients, only 23.4% of patients with VTE in the first 6 months were in the high-risk group (≥3) [3]. The AVERT and CASSINI trials enrolled patients with a score of 2 or more [4, 9].
Thromboprophylaxis in cancer patients
| Situation | Recommendation | Evidence |
|---|---|---|
| Inpatient with acute illness or reduced mobility | Pharmacological prophylaxis with LMWH (with CrCl below 30, preferably unfractionated heparin) during admission, stopped at discharge; DOACs are not routinely recommended | ASH (conditional recommendation) and ITAC grade 1B [1, 2] |
| Major cancer surgery | LMWH once daily or low-dose unfractionated heparin three times a day, for at least 7 to 10 days; after major abdominal or pelvic surgery (open or laparoscopic), up to 4 weeks | ITAC grade 1A; ASH extended prophylaxis after discharge for abdominopelvic surgery [1, 2] |
| Timing of surgical prophylaxis | ITAC: 2 to 12 hours before surgery; ASH prefers starting after surgery | [1, 2] |
| Outpatient on systemic treatment with Khorana ≥2 and low bleeding risk | Prophylactic-dose apixaban or rivaroxaban (or LMWH) | ITAC grade 1B, ASCO 2020 and ASH for high risk [1, 2, 5] |
| Advanced or metastatic pancreatic cancer on treatment | LMWH (grade 1A) or rivaroxaban or apixaban (grade 1B) at low bleeding risk | [2] |
| Advanced lung cancer | Routine LMWH prophylaxis is not recommended outside trials | [2] |
| Myeloma on thalidomide, lenalidomide or pomalidomide | Low-dose aspirin, prophylactic-dose LMWH or fixed-dose warfarin; LMWH for higher risk | ASH (conditional recommendation), ITAC grade 1A for giving prophylaxis [1, 2] |
| Central venous catheter | Routine anticoagulant prophylaxis is not recommended; catheter on the right side in the jugular vein with the tip at the junction of the superior vena cava and right atrium; an implanted port is preferred over a PICC | ITAC grades 1A and 1B; ASH [1, 2] |
| Brain tumour | After neurosurgery, LMWH or unfractionated heparin (grade 1A); without surgery, routine pharmacological prophylaxis is not recommended (grade 1B) | [2] |
In cancer patients with mild thrombocytopenia (platelets above 80,000/µL), pharmacological prophylaxis is possible; below that, only on an individual basis with close monitoring [2].
- AVERT: apixaban 2.5 mg twice a day in outpatients with Khorana ≥2 starting chemotherapy reduced VTE over 180 days from 10.2% to 4.2% (HR 0.41), and major bleeding was 3.5% vs 1.8% (HR 2.00) [4].
- CASSINI: rivaroxaban 10 mg daily vs placebo did not produce a significant reduction over 180 days (6.0% vs 8.8%; HR 0.66; P=0.10), but during the on-treatment period reduced incidence from 6.4% to 2.6% (HR 0.40); major bleeding was 2.0% vs 1.0% [9].
- In a meta-analysis of these two trials, DOACs reduced overall VTE (RR 0.56), but the reduction in symptomatic VTE was not significant (RR 0.58; confidence interval 0.29 to 1.13) [2].
- Surgery: in ENOXACAN II, continuing enoxaparin 40 mg for up to 4 weeks after abdominal or pelvic surgery for cancer reduced venographic VTE from 12.0% to 4.8% without a significant increase in bleeding [10]. The 2023 ASCO update also added apixaban and rivaroxaban as options for extended prophylaxis after cancer surgery (weak recommendation) [11].
- Myeloma: the IMWG recommended aspirin for patients with at most one risk factor, and LMWH (equivalent to enoxaparin 40 mg a day) for two or more risk factors and for all patients receiving high-dose dexamethasone or doxorubicin [12]; the lenalidomide label recommends risk-adapted prophylaxis [13].
Treatment of VTE: low-molecular-weight heparin or DOAC
| Trial | Comparison | Recurrent VTE | Major bleeding | Note |
|---|---|---|---|---|
| CLOT | Dalteparin for 6 months vs a coumarin | 9% vs 17% (HR 0.48) | 6% vs 4% (not significant) | The basis for LMWH superiority over warfarin [16] |
| CATCH | Tinzaparin vs warfarin | 7.2% vs 10.5% (HR 0.65; P=0.07) | No difference (HR 0.89) | Less clinically relevant non-major bleeding with tinzaparin [17] |
| Hokusai VTE Cancer | LMWH for at least 5 days, then edoxaban vs dalteparin | 7.9% vs 11.3% | 6.9% vs 4.0% | Non-inferiority for the composite of recurrence or major bleeding [14] |
| SELECT-D | Rivaroxaban vs dalteparin | 4% vs 11% (HR 0.43) | 6% vs 4% (HR 1.83) | Clinically relevant non-major bleeding 13% vs 4% [15] |
| Caravaggio | Apixaban vs dalteparin | 5.6% vs 7.9% (HR 0.63) | 3.8% vs 4.0% (HR 0.82) | Non-inferior without an increase in major bleeding [6] |
| CASTA-DIVA | Rivaroxaban vs dalteparin (3 months) | 6.4% vs 10.1% | 1.4% vs 3.7% | The sample size was insufficient to prove non-inferiority [18] |
| CANVAS | Any DOAC vs any LMWH (physician's choice) | 6.1% vs 8.8% | 5.2% vs 5.6% | Non-inferiority for 6-month recurrence [19] |
| Meta-analysis (2607 patients) | DOAC vs LMWH | RR 0.68 (not significant) | RR 1.36 (not significant) | Caution at high bleeding risk [20] |
The LMWH dose in the comparator arm of the DOAC trials was dalteparin 200 units/kg once daily for the first month and then 150 units/kg [6, 14, 15].
Choosing an anticoagulant in cancer-associated VTE
- 1
Assessment before choosing
Assess the bleeding risk (especially untreated gastrointestinal or genitourinary lesions), platelet count, creatinine clearance, strong drug interactions and GI absorption; a DOAC is recommended when CrCl is ≥30 mL/min and there are no strong drug interactions or GI absorption problems [2].
- 2
Patient without a high risk of GI or genitourinary bleeding
DOAC or LMWH: apixaban or rivaroxaban from day 1, or edoxaban after at least 5 days of parenteral anticoagulation (grade 1A) [2]. For short-term treatment (3 to 6 months), ASH prefers a DOAC over LMWH (conditional recommendation) [1], and ASCO added apixaban to the treatment options with a strong recommendation [11].
- 3
Gastrointestinal (especially upper GI) or genitourinary cancer
Edoxaban and rivaroxaban have caused more bleeding than LMWH in these cancers [5]; LMWH is more suitable and DOACs should be used with caution [2]. In Caravaggio, major bleeding in patients with GI cancer was 9 patients in each group, and apixaban showed no increase in GI bleeding [21].
- 4
- 5
Recurrent VTE during anticoagulation
ITAC: increase the LMWH dose by 20 to 25% or switch to a DOAC; with recurrence on a DOAC, switch to LMWH; with recurrence on a vitamin K antagonist, switch to LMWH or a DOAC [2]. With recurrence on therapeutic LMWH, ASH suggests increasing to a supratherapeutic dose or continuing the same dose, and does not recommend an inferior vena cava filter (unless anticoagulation is contraindicated) [1].
Special situations
Difficult clinical situations
Thrombocytopenia
Full-dose anticoagulation with platelets above 50,000/µL and no bleeding; below that, an individual decision with the utmost caution [2]. In a prospective study (platelets below 100,000), 60-day major bleeding was 12.8% with full dose and 6.6% with an adjusted dose [2]. Dalteparin label: platelets 50,000 to 100,000, reduce the daily dose by 2500 units; 50,000 or less, stop until above 50,000 [22].
Brain tumour (primary or metastatic)
LMWH or a DOAC can be used (ITAC grade 2A) [2]. In a retrospective cohort, 12-month intracranial haemorrhage in primary brain tumours was zero with a DOAC and 36.8% with LMWH, and no increase was seen with DOACs in brain metastases [23]. Therapeutic enoxaparin in brain metastases did not increase the risk of haemorrhage, but melanoma and kidney cancer bled about 4 times as often as lung cancer [24].
Catheter-related thrombosis
Incidental and subsegmental pulmonary embolism
ASH prefers short-term anticoagulation over observation [1], and ITAC manages incidental VTE like symptomatic VTE [2]. In a prospective cohort of 695 patients, 12-month recurrence despite treatment was 6.0%, with no difference between subsegmental (6.4%) and proximal embolism (6.0%) [25]. In visceral or splanchnic thrombosis, short-term treatment or observation are both acceptable [1].
DOAC drug interactions
Apixaban with combined strong P-gp and CYP3A4 inhibitors: reduce the dose by 50% (if the patient is on 2.5 mg twice a day, combined use is contraindicated); do not use with combined strong inducers [26]. Do not use rivaroxaban with combined strong P-gp and CYP3A inhibitors or inducers [27]. Edoxaban is reduced to 30 mg with some P-gp inhibitors [28].
Pregnancy and obesity
In a pregnant cancer patient, LMWH for treatment and prophylaxis; avoid vitamin K antagonists and DOACs. In an obese patient, consider a higher LMWH dose for prophylaxis in cancer surgery [2].
Duration of treatment and extended treatment
- LMWH or a DOAC for at least 6 months (ITAC grade 1A); after 6 months, continue or stop based on benefit and risk, tolerance, drug availability, patient preference and cancer activity [2].
- In active cancer, ASH prefers long-term anticoagulation (beyond 6 months) and indefinite continuation over stopping, and suggests a DOAC or LMWH for this phase [1].
- Reduced dose in the extended phase: in API-CAT (1766 patients with active cancer after at least 6 months of treatment), apixaban 2.5 mg vs 5 mg twice a day for 12 months kept recurrent VTE non-inferior (2.1% vs 2.8%) and reduced clinically relevant bleeding (12.1% vs 15.6%; HR 0.75) [7]. In the smaller EVE trial (360 patients), major or clinically relevant bleeding was 8.9% vs 12.2%, which was not significant, and recurrence was 5.0% in both groups [29].
- The apixaban label has approved 2.5 mg twice a day and the rivaroxaban label 10 mg daily after at least 6 months of treatment to reduce the risk of recurrence [26, 27]; the safety and efficacy of dalteparin beyond 6 months in cancer have not been studied [22].
Treatment regimens and doses
Treatment regimens and doses: index10 regimens
- Kidney: calculate creatinine clearance before starting (with actual body weight for rivaroxaban) [27]. Enoxaparin with CrCl below 30: treatment 1 mg/kg once daily and prophylaxis 30 mg daily [30]; dalteparin with CrCl below 30: adjust the dose by anti-Xa level (target 0.5 to 1.5 units/mL, 4 to 6 hours after the third or fourth dose) [22]; do not use rivaroxaban with CrCl below 15 [27]; edoxaban 30 mg with CrCl 15 to 50 [28].
- Platelets: heparins can cause heparin-induced thrombocytopenia; monitor platelets [22].
- Interactions: ketoconazole, itraconazole and ritonavir are combined strong P-gp and CYP3A4 inhibitors, and rifampicin, carbamazepine, phenytoin and St John's wort are combined inducers; review the patient's concomitant medicines before a DOAC [26, 27].
- Invasive procedures: stop apixaban at least 48 hours before surgery with moderate or high bleeding risk and 24 hours before a low-risk procedure; bridging is usually not needed [26].
- Missed apixaban dose: take it as soon as possible on the same day and do not double the dose [26].
Treatment of cancer-associated VTE
Therapeutic enoxaparin
Initial and maintenance treatment of cancer-associated VTE (CrCl ≥30); preferred at high risk of GI or genitourinary bleedingCycle length: Daily
Initial and maintenance treatment of cancer-associated VTE (CrCl ≥30); preferred at high risk of GI or genitourinary bleeding
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Twice-daily regimen | |||
| Enoxaparin | 1 mg/kg every 12 hours | Subcutaneous | Continuous |
| Once-daily regimen (inpatient) | |||
| Enoxaparin | 1.5 mg/kg once a day | Subcutaneous | Continuous, at the same time each day |
The doses are from the enoxaparin label for treatment of DVT with or without pulmonary embolism; with CrCl below 30, 1 mg/kg once daily [30]. ITAC prefers once-daily LMWH unless twice-daily dosing is needed (bleeding risk, moderate renal impairment or an interventional procedure), and in that case considers only enoxaparin 1 mg/kg twice a day suitable [2].
Therapeutic apixaban (Caravaggio)
Symptomatic or incidental cancer-associated VTE (proximal DVT or pulmonary embolism)Cycle length: Daily
Symptomatic or incidental cancer-associated VTE (proximal DVT or pulmonary embolism)
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Days 1 to 7 | |||
| Apixaban | 10 mg twice a day | Oral | First 7 days |
| From day 8 | |||
| Apixaban | 5 mg twice a day | Oral | Continuous |
Reduce the dose by 50% with combined strong P-gp and CYP3A4 inhibitors; do not use with combined strong inducers. For DVT/PE treatment, the label does not recommend dose adjustment for renal impairment (even dialysis patients), because the recommendation is based on pharmacokinetic data and the trials did not enrol patients on dialysis or with CrCl below 15 [26]. In Caravaggio, recurrence was 5.6% vs 7.9% with dalteparin and major bleeding 3.8% vs 4.0% [6].
Evidence: Caravaggio (2020)
Therapeutic rivaroxaban (SELECT-D)
Cancer-associated VTE in a patient without a high risk of GI or genitourinary bleeding (CrCl ≥15)Cycle length: Daily
Cancer-associated VTE in a patient without a high risk of GI or genitourinary bleeding (CrCl ≥15)
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Days 1 to 21 | |||
| Rivaroxaban | 15 mg twice a day with food | Oral | First 21 days |
| From day 22 | |||
| Rivaroxaban | 20 mg once a day with food | Oral | Continuous, at the same time each day |
Do not use with CrCl below 15, and use with close bleeding monitoring at 15 to below 30; do not use with combined strong P-gp and CYP3A inhibitors or inducers [27]. In SELECT-D, 6-month recurrence was 4% vs 11% with dalteparin, but clinically relevant non-major bleeding was more common (13% vs 4%) [15].
Evidence: SELECT-D (2018)
Therapeutic dalteparin (CLOT)
Extended treatment of symptomatic VTE in adults with cancerCycle length: Daily
Extended treatment of symptomatic VTE in adults with cancer
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| First month | |||
| Dalteparin | 200 units/kg once a day (maximum 18,000 units) | Subcutaneous | First 30 days |
| Months 2 to 6 | |||
| Dalteparin | About 150 units/kg once a day (maximum 18,000 units) | Subcutaneous | Daily |
Platelets 50,000 to 100,000/µL: reduce the daily dose by 2500 units until platelets reach 100,000 or more; 50,000 or less: stop until above 50,000. CrCl below 30: adjust by anti-Xa level (target 0.5 to 1.5 units/mL) [22]. In CLOT, dalteparin vs a coumarin reduced 6-month recurrence from 17% to 9% [16].
Edoxaban after LMWH (Hokusai VTE Cancer)
Cancer-associated VTE in a patient without a high risk of GI bleeding, after at least 5 days of parenteral anticoagulationCycle length: Daily
Cancer-associated VTE in a patient without a high risk of GI bleeding, after at least 5 days of parenteral anticoagulation
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Day 1 to at least day 5 | |||
| LMWH | Therapeutic dose | Subcutaneous | At least 5 days (label: 5 to 10 days) |
| After that | |||
| Edoxaban | 60 mg once a day (30 mg with CrCl 15 to 50, weight ≤60 kg or use of certain P-gp inhibitors) | Oral, with or without food | Continuous |
The dose and dose-reduction criteria are from the edoxaban label [28]. In Hokusai VTE Cancer, recurrence was lower (7.9% vs 11.3%) but major bleeding higher (6.9% vs 4.0%) than with dalteparin [14]; the excess bleeding was mainly gastrointestinal and in GI cancers, and advanced cancer and low haemoglobin were associated with GI bleeding [31].
Evidence: Hokusai VTE Cancer (2018)
Doses follow the trial protocol, guideline or official drug label (source given in the notes of each regimen). Before prescribing, check blood counts, renal and hepatic function, drug interactions and the patient’s condition, and adjust the dose according to the drug label.
Primary prophylaxis and extended treatment
Prophylactic enoxaparin (inpatients and surgery)
Hospitalised cancer patient with reduced mobility or undergoing abdominal or pelvic surgeryCycle length: Daily
Hospitalised cancer patient with reduced mobility or undergoing abdominal or pelvic surgery
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Medical inpatient | |||
| Enoxaparin | 40 mg once a day | Subcutaneous | During admission (usually 6 to 11 days in the label) |
| Abdominal surgery | |||
| Enoxaparin | 40 mg once a day; first dose 2 hours before surgery | Subcutaneous | Usually 7 to 10 days; after major abdominal or pelvic cancer surgery, up to 4 weeks |
Prophylactic apixaban (AVERT)
Outpatient with Khorana ≥2 starting chemotherapy with a low bleeding riskCycle length: Daily
Outpatient with Khorana ≥2 starting chemotherapy with a low bleeding risk
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Apixaban | 2.5 mg twice a day | Oral | Continuous |
In AVERT, VTE was 4.2% vs 10.2% and major bleeding 3.5% vs 1.8% [4]. Interactions and kidney considerations as for the therapeutic apixaban regimen [26].
Evidence: AVERT (2019)
Prophylactic rivaroxaban (CASSINI)
High-risk outpatient (Khorana ≥2) on systemic treatment, without DVT on screeningCycle length: Daily
High-risk outpatient (Khorana ≥2) on systemic treatment, without DVT on screening
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Rivaroxaban | 10 mg once a day | Oral | Continuous |
In CASSINI, the reduction in VTE over the whole 180 days was not significant, but during the on-treatment period it was 2.6% vs 6.4%; major bleeding 2.0% vs 1.0% [9].
Evidence: CASSINI (2019)
Prophylactic dalteparin (abdominal cancer surgery and inpatients)
Abdominal surgery for malignancy, or a medical patient with severely restricted mobilityCycle length: Daily
Abdominal surgery for malignancy, or a medical patient with severely restricted mobility
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Abdominal surgery for malignancy | |||
| Dalteparin | 5000 units the evening before surgery, then daily (or 2500 units 1 to 2 hours before surgery, 2500 units 12 hours later, then 5000 units daily) | Subcutaneous | Usually 5 to 10 days |
| Medical inpatient | |||
| Dalteparin | 5000 units once a day | Subcutaneous | 12 to 14 days in trials |
Apixaban or rivaroxaban in the extended phase (after 6 months)
VTE associated with active cancer after at least 6 months of full anticoagulationCycle length: Daily
VTE associated with active cancer after at least 6 months of full anticoagulation
| Drug | Dose | Route | Schedule |
|---|---|---|---|
| Option 1 | |||
| Apixaban | 2.5 mg twice a day | Oral | Continuous |
| Option 2 | |||
| Rivaroxaban | 10 mg once a day | Oral, with or without food | Continuous |
Doses follow the trial protocol, guideline or official drug label (source given in the notes of each regimen). Before prescribing, check blood counts, renal and hepatic function, drug interactions and the patient’s condition, and adjust the dose according to the drug label.
Key trials
Key evidence on cancer-associated thrombosis
5 itemsApixaban for the Treatment of Venous Thromboembolism Associated with Cancer
Comparison of an Oral Factor Xa Inhibitor With Low Molecular Weight Heparin in Patients With Cancer With Venous Thromboembolism: Results of a Randomized Trial (SELECT-D)
Apixaban to Prevent Venous Thromboembolism in Patients with Cancer
Rivaroxaban for Thromboprophylaxis in High-Risk Ambulatory Patients with Cancer
Edoxaban for the Treatment of Cancer-Associated Venous Thromboembolism
- Khorana components: stomach and pancreas 2 points; lung, lymphoma, gynaecological, bladder and testicular 1; platelets ≥350,000, haemoglobin below 10 or an ESA, white cells above 11,000 and BMI ≥35, 1 point each [8].
- Most VTE occurs in patients who are not Khorana high risk (only 23.4% in the ≥3 group) [3].
- CASSINI was negative over the whole 180 days; benefit was seen only during the on-treatment period [9].
- Of the DOACs, only apixaban and rivaroxaban are started without initial LMWH; edoxaban after at least 5 days of parenteral anticoagulation [1, 2].
- Edoxaban and rivaroxaban caused more bleeding in GI cancers; apixaban in Caravaggio did not increase major bleeding [5, 6].
- Full-dose anticoagulation with platelets above 50,000; prophylaxis with platelets above 80,000 [2].
- Catheter thrombosis: at least 3 months and as long as the catheter is in; do not remove a sound, working catheter [1, 2].
- Treat incidental pulmonary embolism like symptomatic embolism [2].
- With CrCl below 30: unfractionated heparin then a vitamin K antagonist, or LMWH with anti-Xa monitoring [2].
- Pregnancy: LMWH only [2].
- Extended phase: apixaban 2.5 mg twice a day was non-inferior with less bleeding in API-CAT [7].
Self-assessment questions
A 60-year-old man with metastatic pancreatic cancer before starting chemotherapy; platelets 380,000/µL, haemoglobin 11 g/dL, white cells 8,000 and BMI 24. What is the Khorana score and the recommended action?
A 55-year-old woman with untreated stomach cancer (tumour in place) and symptomatic pulmonary embolism. Which anticoagulant is more suitable?
LMWH, because in GI cancers, especially upper GI, edoxaban and rivaroxaban have caused more bleeding, and ITAC recommends caution [2, 5]. Apixaban showed no increase in GI bleeding in Caravaggio and can be used cautiously as an alternative if needed [21].
A patient with leukaemia, a proximal DVT and platelets of 35,000/µL. What do you do?
With platelets below 50,000, the decision about treatment and dose is individual and taken with the utmost caution [2]; the dalteparin label recommends temporary interruption with platelets of 50,000 or less [22]. In a prospective study, an adjusted dose caused less major bleeding than a full dose (6.6% vs 12.8%) [2].
A patient with glioblastoma and pulmonary embolism. Is anticoagulation absolutely contraindicated?
No; ITAC suggests treatment with LMWH or a DOAC in brain tumours (grade 2A) [2]. In one cohort, intracranial haemorrhage in primary brain tumours was lower with a DOAC than with LMWH (zero vs 36.8%) [23]. Even so, in glioma, full-dose anticoagulation vs no anticoagulation has been associated with more intracerebral haemorrhage (OR 3.66) [2].
An incidental subsegmental pulmonary embolism is seen on a staging CT in a patient with colon cancer. Is treatment needed?
A patient with an arm vein thrombosis caused by a port that works and is not infected. Do you remove the port?
A patient with active cancer has had 6 months of apixaban 5 mg twice a day. What is the option for continuing?
References
31 referencesShow all references, 5 with a study cardClose the reference list
Numbers in the text, such as [1], refer to these sources. Sources with a “Study card” button are summarised in the site’s evidence library.
- 1
- 22022 international clinical practice guidelines for the treatment and prophylaxis of venous thromboembolism in patients with cancer, including patients with COVID-19
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- 4
- 5
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- 7
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- 10
- 11
- 12Prevention of thalidomide- and lenalidomide-associated thrombosis in myeloma
- 13REVLIMID (lenalidomide) capsules — Prescribing Information
- 14
- 15
- 16
- 17Tinzaparin vs Warfarin for Treatment of Acute Venous Thromboembolism in Patients With Active Cancer: A Randomized Clinical Trial
- 18Rivaroxaban vs Dalteparin in Cancer-Associated Thromboembolism: A Randomized Trial
- 19Direct Oral Anticoagulants vs Low-Molecular-Weight Heparin and Recurrent VTE in Patients With Cancer: A Randomized Clinical Trial
- 20Direct oral anticoagulants for cancer-associated venous thromboembolism: a systematic review and meta-analysis
- 21
- 22
- 23
- 24Intracranial hemorrhage in patients with brain metastases treated with therapeutic enoxaparin: a matched cohort study
- 25
- 26
- 27
- 28
- 29Extending venous thromboembolism secondary prevention with apixaban in cancer patients. The EVE trial
- 30
- 31Risk factors for gastrointestinal bleeding in patients with gastrointestinal cancer using edoxaban
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