Is extended thromboprophylaxis necessary in elective colorectal cancer surgery?

The incidence of venous thromboembolism after curative colon cancer surgery within an enhanced recovery after surgery programme

AIM

Based on three randomised controlled trials performed more than a decade ago, several national guidelines recommend prolonged venous thromboprophylaxis for 28 days following elective surgery for colon cancer. None of these studies were conducted within enhanced recovery after surgery setting. Newer studies indicate that prolonged prophylaxis might not be necessary with enhanced recovery after surgery. We aimed to provide further evidence to this unresolved discussion.

METHOD

Retrospective study of patients undergoing elective surgery for colon cancer stage I-III with enhanced recovery after surgery in the Capital Region of Denmark from 2014 to 2017. Patients were excluded if discharged on postoperative day 28 or later, dying before discharge, undergoing concomitant rectum resection, or discharged with vitamin K antagonists, direct-oral anticoagulants, or low molecular weight heparin treatment. All patients received only low-dose low molecular weight heparin as prophylaxis during their admission. The primary endpoint was symptomatic lower limb deep venous thrombosis or pulmonary embolism diagnosed within 60 days postoperatively.

RESULTS

Out of the included population of 1806 patients, only three experienced a symptomatic venous thromboembolic event; none was fatal. Two had pulmonary embolism associated with pneumonia, while one patient was diagnosed with lower limb deep venous thrombosis at postoperative day 15 after an uncomplicated course with first discharge at postoperative day 2.

CONCLUSION

The risk of symptomatic venous thromboembolism after elective surgery for colon cancer with enhanced recovery after surgery seems negligible even without prolonged prophylaxis. The current guidelines need to be reconsidered.

Venous Thromboembolism Following Major Abdominal Surgery for Cancer: A Guide for the Surgical Intern

BACKGROUND

Venous thromboembolism (VTE) is a term used to compositely describe deep vein thrombosis (DVT) and pulmonary embolism (PE). Overall, the incidence of VTE after major abdominal and pelvic surgery has been reported to be between 10% and 40%.

OBJECTIVE

To estimate the incidence of post-operative VTE in patients undergoing major abdominal surgery for cancer, to identify risk factors associated with VTE, and to assess available thromboprophylaxis tools.

METHODS

A Medline and Cochrane literature search from database inception until February 1st, 2021 was performed according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines.

RESULTS

Thirty-one studies met our eligibility criteria and were included in the current review. In total, 435,492 patients were identified and the overall incidence of VTE was 2.19%( 95% CI: 1.82-2.38). Τhe following risk factors were associated with VTE: smoking, advanced age (>70 years), a history of diabetes mellitus, American Society of Anesthesiologists' (ASA) classification of Physical Health class III or IV, a history of cardiovascular or pulmonary disease, a history of DVT or PE, elevated plasma fibrinogen level, c-reactive protein (CRP) level, cancer stage III or IV, postoperative acute respiratory distress syndrome (ARDS), prolonged postoperative hospital stay, previous steroid use, history of Inflammatory Bowel Disease (IBD), heart failure and neoadjuvant and adjuvant chemotherapy.

CONCLUSION

VTE remains an important complication after major abdominal surgery for cancer and seems to increase mortality rates.

Safety and effectiveness of biosimilar enoxaparin (Inhixa) for the prevention of thromboembolism in medical and surgical inpatients

In 2016, biosimilar enoxaparin (Inhixa^®, Techdow) was introduced in European markets with the same indications as branded enoxaparin (Clexane^®, Sanofi). Its use is constantly increasing in clinical practice, however, little information from post-marketing clinical trials is available on its safety and effectiveness. We conducted an observational, retrospective study to assess the safety and effectiveness of Inhixa in preventing venous thromboembolism (VTE) in medically ill patients and in patients undergoing major abdominal surgery. We then compared our results with the incidence of symptomatic VTE and bleeding events during treatment with Clexane by pooling the results of clinical studies carried out in the same settings. We enrolled 381 patients, 189 admitted to a Medical Department and 192 to a Surgical Department from two single institutions. The incidence of major bleeding events was 1.8% globally (95% IC 0.7-3.8), 1.6% in medical patients (95% IC 0.3-4.6) and 2.1% in surgical patients (95% IC 0.6-5.3). VTE rate was 0.5% in the whole population (95% IC 0.1-1.9) and 0.5% (95% IC 0.01-2.9) in each group, respectively. The pooled estimate of the incidence of major bleeding with Clexane was 0.5% (IC 95%: 0.2-1.1) in medical patients and 2.6% (IC 95% 1.3-5.1) in surgical patients. The incidence of thrombotic events was 0.6% (IC 95%: 0.2-1.8) and 0.7% (CI95% 0.3-1.6), respectively. The incidence of bleeding and thrombosis in medical and surgical patients receiving Inhixa was low suggesting biosimilar enoxaparin is a valid alternative to branded enoxaparin.

Extended versus inpatient thromboprophylaxis with heparins following major open abdominopelvic surgery for malignancy: a systematic review of efficacy and safety

Background

Patients undergoing open abdominopelvic procedures for malignancy are at high risk of postoperative venous thromboembolism (VTE). This risk can be mitigated with prophylaxis; however, optimum duration in this population remains unknown. Our objective was to conduct a systematic review of contemporary literature on the use of heparin thromboprophylaxis following major open pelvic surgery for malignancy, comparing the efficacy and safety of extended duration to inpatient treatment.

Methods

A study protocol describing search strategy and inclusion and exclusion criteria was developed and registered with PROSPERO. A literature review was conducted in accordance with the protocol.

Results

Literature review identified only 4 studies directly comparing extended and inpatient duration prophylaxis, with a combined population of 3198 and 3135 patients for VTE rate and bleeding events, respectively. Despite many studies reporting lower VTE rates in patients receiving extended prophylaxis, no statistically significant difference in rates of postoperative VTE (p = 0.18) or bleeding complications (p = 0.43) was identified between patients receiving extended duration prophylaxis and those receiving inpatient only prophylaxis.

Conclusion

On the review of contemporary literature, no significant difference was found in rates of postoperative VTE or bleeding complications between patients receiving extended duration heparin VTE prophylaxis and those receiving inpatient prophylaxis after open abdominopelvic surgery for malignancy.

This raises the question of how extended duration prophylaxis has become common practice in this population, and whether this needs to be re-evaluated.

Rivaroxaban for extended antithrombotic prophylaxis after laparoscopic surgery for colorectal cancer. Design of the PRO-LAPS II STUDY

BACKGROUND

The clinical benefit of extending prophylaxis for venous thromboembolism (VTE) beyond hospital discharge after laparoscopic surgery for cancer is undefined. Extended prophylaxis with rivaroxaban is effective in reducing post-operative VTE after major orthopedic surgery without safety concern.

METHODS

PROLAPS II is an investigator-initiated, randomized, double-blind study aimed at assessing the efficacy and safety of extended antithrombotic prophylaxis with rivaroxaban compared with placebo after laparoscopic surgery for colorectal cancer in patients who had received antithrombotic prophylaxis with low molecular-weight heparin for 7 ± 2 days (NCT03055026). Patients are randomized to receive rivaroxaban (10 mg once daily) or placebo for 3 weeks (up to day 28 ± 2 from surgery). The primary study outcome is a composite of symptomatic objectively confirmed VTE, asymptomatic ultrasonography-detected DVT or VTE-related death at 28 ± 2 days from laparoscopic surgery. The primary safety outcome is major bleeding defined according to the International Society of Thrombosis and Haemostasis. Symptomatic objectively confirmed VTE, asymptomatic ultrasonography-detected DVT, major bleeding or death by day 28 ± 2 and by day 90 from surgery are secondary outcomes. Assuming an 8% event rate with placebo and 60% reduction in the primary study outcome with rivaroxaban, 323 patients per group are necessary to show a statistically significant difference between the study groups.

DISCUSSION

The PROLAPS II is the first study with an oral anti-Xa agent in cancer surgery. The study has the potential to improve clinical practice by answering the question on the clinical benefit of extending prophylaxis after laparoscopic surgery for colorectal cancer.

Venous thromboembolism in colorectal surgery: Incidence, risk factors, and prophylaxis

Colorectal surgery is associated with a high risk of perioperative venous thromboembolism (VTE), and this risk is especially high following colorectal cancer resection and surgery for inflammatory bowel disease. Previous analyses of large databases have reported the incidence of postoperative VTE in this population to be approximately 1.1%-2.5%. Therefore, to minimize this risk, patients should be offered appropriate prophylaxis, which may involve a combination of mechanical and pharmacologic prophylaxis with low-dose unfractionated heparin or low molecular weight heparin as recommended by several guidelines. Prior to initiation of treatment, appropriate risk stratification should be performed according to the patients' basic and disease-related as well as procedure-related risk factors, and post-operative factors. Furthermore, a risk-benefit calculation that takes into account patients' VTE and bleeding risk should be performed prior to starting pharmacologic prophylaxis and to help determine the duration of treatment.

Incidence, risk factors, and outcomes of venous thromboembolism after oncologic surgery: A systematic review and meta-analysis

BACKGROUND

The risk and prognosis of VTE associated with oncologic surgery need to be quantified to guide patient management. We aimed to examine the availability of data and to report the incidence of venous thromboembolism (VTE) in cancer patients after surgery, as well as the clinical outcomes of VTE following oncologic surgery.

METHODS

We searched multiple databases for terms related to VTE after oncologic surgery from inception to November 1, 2017. A random-effects meta-analysis was done to calculate the pooled incidence of VTE.

RESULTS

Of the 8611 citations identified, 136 studies including 1,481,659 patients met the eligibility criteria. The overall incidence of VTE was estimated to be 2.3% (95% CI 2.1-2.5). Bone and soft tissue cancer (10.6%, 95% CI 2.9-18.2) and lung cancer (8.1%, 95% CI 3.7-12.6) were associated with the highest and second highest risk of postoperative VTE, respectively. Age (standardized mean difference [SMD] = 0.46, 95% CI 0.40-0.53; I² = 93.8%), radiation (OR 1.29, 95% CI 1.03-1.62; I² = 34.6%), transfusion (OR 1.96, 95% CI 1.48-2.59; I² = 57.0%), and operative time (SMD = 1.12, 95% CI 1.07-1.16; I² = 100%) were possible risk factors for postoperative VTE. Patients with VTE versus those without had increased odds of all-cause fatal events (11.15, 95% CI 4.07-30.56; I² = 92.0%).

CONCLUSIONS

The risk of VTE after oncologic surgery remains high, and this risk varied according to the cancer type, study region, surgical location, and thromboprophylactic strategy. VTE is associated with increased mortality at the early stage of cancer surgery.

Incidence of venous thromboembolic events in enhanced recovery after surgery for colon cancer: a retrospective, population-based cohort study

AIM

Both the Danish and the National Institute of Clinical Excellence (NICE) guidelines recommend prolonged thromboprophylaxis (PT) with low-molecular-weight heparin (LMWH) for 28 days postoperatively after elective surgery for colon cancer. The evidence relies on data from two randomized clinical trials (RCTs) that included not only colon cancers but also other abdominal cancers or benign colorectal diseases. Neither of those studies investigated the risk of venous thromboembolism (VTE) under enhanced recovery after surgery (ERAS). We aim to describe the risk of VTE and estimate the cost of preventing one case of VTE by PT under ERAS.

METHOD

This was a retrospective study of 2230 patients undergoing elective surgery for colon cancer Stage I-III in the Capital Region of Denmark, 1 June 2008 to 31 December 2013. Patients who were discharged on postoperative day 28 or later, died during admission or were discharged with a vitamin K antagonist, novel oral anticoagulants or LMWH were excluded. Patients with rectal cancer only were not included. End-points were symptomatic VTE diagnosed within 60 days postoperatively.

RESULTS

Three-hundred and thirty patients were excluded. For the remaining 1893, the median length of stay (LOS) was 4 [interquartile range (IQR): 3-5] days. Of these 1893 patients, four (0.20%) experienced a nonfatal symptomatic VTE. All four patients had other postoperative complications before the VTE. The cost of each symptomatic VTE prevented is estimated to be between £63 709 and £111 455 when medication and home-care nursing are included.

CONCLUSION

The risk of symptomatic VTE after uncomplicated, elective surgery for colon cancer with ERAS seems negligible and the cost-effectiveness of PT to prevent one symptomatic VTE seems questionable.

Extended venous thromboembolism prophylaxis after colorectal cancer surgery: the current state of the evidence

There is level one evidence to support combined mechanical and chemical thromboprophylaxis for 7-10 days after colorectal cancer surgery, but there remains a paucity of data to support extended prophylaxis after discharge. The aim of this clinical review is to summarise the currently available evidence for extended venous thromboprophylaxis after elective colorectal cancer surgery. Clinical review of the major clinical guidelines and published clinical data evaluating extended venous thromboprophylaxis after elective colorectal cancer surgery. Five major guideline recommendations are outlined, and the results of the five published randomised controlled trials are summarised and reviewed with a specific focus on the efficacy and cost-effectiveness of extended heparin prophylaxis to prevent clinically relevant post-operative venous thromboembolism (VTE) after colorectal cancer surgery. Extended VTE prophylaxis after colorectal cancer surgery reduces the incidence of asymptomatic screen detected deep venous thrombosis (DVT) only, with no demonstrable reduction in symptomatic DVT, symptomatic PE, or VTE related death. Evidence for cost-effectiveness is limited. As the incidence of clinical VTE is very low in this patient subgroup overall, future research should be focused on higher risk patient subgroups in whom a reduction in VTE may be both more demonstrable and clinically relevant.

Incidence of pulmonary embolism in patients with newly diagnosed colorectal cancer

BACKGROUND

Studies have suggested a benefit from extended venous thromboprophylaxis post-operatively in colorectal cancer with an assumed base rate of zero venous thromboembolic events prior to treatment. We aim to establish the incidence of pulmonary embolism in patients with newly diagnosed stage III or IV colorectal cancer prior to any treatment.

METHOD

Consecutive patients presenting to a single health service with a new diagnosis of stage III or IV colorectal cancer were identified from a prospective database, for the period between January 2011 and September 2014. Contemporaneous clinical data was reviewed. Included patients had a computerized tomography (CT) chest scan for pre-operative staging for cancer. The diagnosis of pulmonary emboli was made on chest CT.

RESULTS

Of 330 patients identified, 224 had baseline CT chest imaging available for review, of which 107 (47.8%) were technically adequate scans. Pulmonary emboli were identified on five (4.7%) of these 107, including one of five patients (1.7%) with stage III and four of five patients (8.3%) with stage IV disease. None of the 107 patients with adequate scans had post-operative pulmonary emboli or deep vein thrombosis.

CONCLUSION

There is a clinically significant baseline rate of asymptomatic pulmonary emboli in patients with stage III and IV colorectal cancer that can be demonstrated on the staging chest CT scan. Pulmonary emboli described as a post-operative event in previous series may have been present prior to surgery.

Safety and efficacy of fondaparinux for prophylaxis of venous thromboembolism after colorectal cancer resection: a propensity score matched analysis

BACKGROUND/AIMS

The aim of this study was to examine the safety and efficacy of fondaparinux (FPX) for venous thromboembolism (VTE) prophylaxis after colorectal cancer surgery.

METHODS

Records of 953 patients with colorectal cancer who underwent resection between 2006 and 2013 were reviewed. Patients were divided into two groups: the FPX group (n = 362), treated with subcutaneous FPX plus intermittent pneumatic compression (IPC) and the IPC group (n = 591), treated with IPC alone. The incidence of symptomatic VTE, major bleeding, minor bleeding, and other postoperative complications were compared using propensity score matching.

RESULTS

Symptomatic VTE occurred only in one patient (0.2%) in the IPC group. In the FPX group, the incidence of major and minor bleeding was 0.55% (2 of 362) and 9.4% (34 of 362), respectively. After propensity score matching, there were no differences between the two groups in the incidence of symptomatic VTE, major bleeding, and other common postoperative complications. Only the incidence of minor bleeding was significantly higher in the FPX group compared to the IPC group.

CONCLUSION

FPX is potentially an effective form of VTE prophylaxis; it is safe in terms of both postoperative bleeding and other common complications after colorectal cancer surgery.

Occurrence and Prognosis of Symptomatic Venous Thromboembolism in Colorectal Cancer Surgery Patients

PURPOSE

Colorectal cancer (CRC) has a high risk for postoperative thromboembolic complications such as venous thromboembolism (VTE) compared to other surgical diseases, but the relationship between VTE and CRC in Asian patients remains poorly understood. The present study examined the incidence of symptomatic VTE in Korean patients who underwent surgery for CRC. We also identified risk factors, incidence and survival rate for VTE in these patients.

MATERIALS AND METHODS

The patients were identified from the CRC database treated from January 2011 to December 2012 in a single institution. These patients were classified into VTE and non-VTE groups, their demographic features were compared, and the factors which had significant effects on VTE and mortality between the two groups were analyzed.

RESULTS

We analyzed retrospectively a total of 840 patients and the incidence of VTE was 3.7% (31 patients) during the follow-up period (mean, 17.2 months). Histologic subtype (mucinous adenocarcinoma) and previous history of VTE affected the incidence of VTE on multivariate analysis. There was a statistically significant difference in survival rate between the VTE and non-VTE group, but VTE wasn't the factor affecting survival rate on multivariate analysis. Comparing differences in survival rate for each pathologic stage, there was only a significant difference in stage II patients.

CONCLUSION

Among CRC patients after surgery, the incidence of VTE was approximately 3% within 1 year and development of VTE wasn't a significant risk factor for death in our study but these findings are not conclusive due to our small sample size.