High rates of venous thromboembolic events in patients undergoing systemic therapy for urothelial carcinoma: A systematic review and meta-analysis

Venous Thromboembolism Rate in Patients With Bladder Cancer According to the Type of Treatment: A Systematic Review

Bladder cancer (BC) is classified as a high-risk tumour type for venous thromboembolism (VTE). VTE presents an extra challenge in the management of patients with cancer, given the increase in morbidity and mortality on having both conditions.

To summarise the contemporary evidence on the VTE rate in patients with BC according to the stage, type of anti-cancer treatment and highlight VTE rate in the UK and other countries. A systematic review was carried out, and an electronic search for publications between January 2000 and November 2021 was done. Studies recording VTE in BC patients were included, whilst paediatric patients, case reports, studies reporting on a mix of arterial and venous thrombosis, studies reporting DVT or PE only and recorded hospitalised VTE only were excluded. The rate of VTE, country of origin, risk factors and thromboprophylaxis duration for VTE in BC patients were identified.

A total of 38 papers met the search criteria. All publications were original research papers (cohort studies). The overall VTE rate in patients with BC was estimated at 1.9% to 4.7%. For those patients undergoing cystectomy, the VTE rate ranged from 3% to 17.6%; however, the VTE rate in the metastatic stage of BC patients ranged from 3.1% to 5.1%.

The rates of VTE in BC patients are high, further increased by interventions such as surgery and chemotherapy. Thromboprophylaxis measures should be optimised. This review highlighted the fact that the VTE rate in BC varies between studies due to the heterogeneity of risk factors reported.

Risk for Venous Thromboembolic Events in Patients With Advanced Urinary Tract Cancer Treated With First-Line Chemotherapy

BACKGROUND

Venous thromboembolic events (VTEs) frequently occur in cancer patients. Risk assessment models (RAMs) for cancer-associated thrombosis have been proposed. However, advanced urinary tract cancer (aUTC) was not adequately represented in these models. We studied the incidence of VTEs, the risk factors, and the applicability of recently described RAMs.

PATIENTS AND METHODS

Data from 335 patients with aUTC treated with chemotherapy between April 1995 and September 2015 in a single institution were analyzed.

RESULTS

A total of 95.2% received platinum-based first-line chemotherapy. Twenty-nine patients (8.7%) experienced VTEs. The 6-, 12-, and 24-month VTE incidence was 7.4% (95% confidence interval [CI], 4.8-10.6), 8.1% (95% CI, 5.4-11.5) and 9.4% (95% CI, 6.4-13.1), respectively. No significant association of VTE incidence with the Khorana risk score was observed. History of vascular event (VTE and/or arterial thromboembolic event) was significantly associated with the development of VTE. Patients with such history had a 6-, 12-, and 24-month VTE incidence of 16.2% (95% CI, 6.6-29.7), 19.2% (95% CI, 8.4-33.3), and 25.2% (95% CI, 12.5-40.1) compared to 6.2% (95% CI, 3.7-9.4), 6.6% (95% CI, 4.1-10), and 7.1% (95% CI, 4.4-10.6) of those who did not. The discriminatory ability of this factor adjusted for leucocyte count, sex, Eastern Cooperative Oncology Group performance status, and type of chemotherapy reached 0.79 (95% CI, 0.71-0.87) compared to the 0.58 (95% CI, 0.49-0.66) for the Khorana risk score.

CONCLUSION

Development of tumor-specific algorithms for the risk of VTEs is advisable. Patients with aUTC and a history of vascular events are at high risk for VTE development, and prophylaxis should be prospectively studied in this group.

Venous Thromboembolism and Peri-Operative Chemotherapy for Muscle-Invasive Bladder Cancer: A Population-based Study

Background:

Chemotherapy and major pelvic surgery are established risk factors for venous thromboembolism (VTE). We evaluate the incidence rate, timing, and factors associated with VTE in patients with bladder cancer who underwent radical cystectomy and peri-operative chemotherapy in routine clinical practice.

Methods:

Electronic records of treatment were linked to the population-based Ontario Cancer Registry to identify all patients who underwent cystectomy for bladder cancer in Ontario 1994–2013. VTE events within 6 months of before or after cystectomy were identified using diagnostic codes recorded on hospital admissions and emergency department visits. Multivariable logistic regression was used to analyze factors associated with VTE prior to surgery, within 90-days of cystectomy, and 120-days after the start of adjuvant chemotherapy.

Results:

4205 patients had cystectomy and 26% (1084/4205) received peri-operative chemotherapy. The overall incidence rate of VTE within 6 months of cystectomy was 9% (363/4205). VTE rate was highest among those patients treated with neoadjuvant chemotherapy (NACT) compared to patients treated with no chemotherapy or only adjuvant chemotherapy (ACT) (12% vs 8% vs 9%, p = 0.002). Among all VTE events, 10%, 28%, and 61% occurred before, during, and after hospitalization for cystectomy. Pre-operative VTE rate was highest among cases treated with NACT (4%) compared to patients with no chemotherapy (<1%) or ACT (<1%) (p < 0.001). VTE within 90 days of surgery was associated with greater length of hospital admission (p < 0.001) across all treatment groups.

Conclusions:

A substantial proportion of patients treated with peri-operative chemotherapy will develop VTE. The majority of these occur after discharge from hospital following cystectomy. Extended thromboprophylaxis treatment in high-risk patients including those who receive peri-operative chemotherapy should be considered.

Thromboembolism in Patients with Bladder Cancer: Incidence, Risk Factors and Prevention

Patients with bladder cancer are at high risk of developing both venous and arterial thromboembolic events. Factors that contribute to this phenomenon include the hypercoagulable state induced by the malignancy itself, medical comorbidities that are common in this predominantly elderly patient population as well as treatments such as prolonged pelvic surgery and cisplatin-based chemotherapy. While formal guidelines address prevention of venous thromboembolism in patients undergoing radical cystectomy, consensus regarding the role of pharmacologic prophylaxis in patients with bladder cancer being treated with chemotherapy, either with neoadjuvant or adjuvant intent in conjunction with radical cystectomy, as part of bladder preservation protocols or for metastatic disease, has proved elusive. The present narrative review was undertaken to define the incidence of and identify risk factors for thromboembolism among patients with bladder cancer, as well as to assess the efficacy of pharmacologic prophylaxis in reducing the risk of thromboembolism in this patient population.

Perioperative venous thromboembolism in urologic oncology procedures, risk factors, and prevention

PURPOSE OF REVIEW

Venous thromboembolism (VTE) is a common complication during the perioperative period for major urologic oncology operations. The present review focuses on the risk factors, the mechanisms of hypercoagulability in this patient population, and the timing and prevention of VTE.

RECENT FINDINGS

Although the vast majority of patients undergoing major urologic oncology operations do not develop VTEs, when they do develop they can be fatal. The risk factors for VTEs are important to identify in this patient population. The timing of VTE events are also essential to understanding their prevention. Prevention focused around the perioperative period is the best way to reduce fatal complications secondary to a VTE event.

SUMMARY

VTEs are common and can potentially be fatal. Prevention in high-risk patients during the most vulnerable perioperative time period should be the focus of clinical efforts to reduce VTE complications and the associated morbidity and mortality.