Cancer-associated thrombosis in urological malignancy- a tertiary referral centre experience

Background Cancer-associated thrombosis (CAT), including arterial and venous thromboembolic events, is the second leading cause of death in patients with malignancy. The risk of CAT is influenced by several factors, including cancer type. In urologic oncology, there is significant heterogeneity in CAT prevalence, with urothelial, renal, and testicular cancers having the highest reported risk of thromboembolic disease. Purpose To investigate the prevalence of CAT in patients with urological malignancies in relation to comorbidities and risk factors throughout medical follow-up at a referral centre for urologic oncology. Methods A retrospective, cross-sectional study was conducted in a tertiary urology hospital in 582 patients with different urogenital cancers enrolled in the oncology program between January 2022 and July 2023 and followed-up until December 2024. Results 582 patients with genitourinary cancer (mean age 70 ± 7.72 years, 86% male) had urothelial (45%), prostate (43%), renal (10%), penile (1%), and testicular (1%) malignancies. 39 patients (6.7%) had two cancers at enrolment. The prevalence of CAT was 3.44% (20 patients) and was equally distributed between arterial and venous thrombosis. CAT occurred mainly in patients with prostate (55%) and urothelial (25%) cancers, followed by renal (15%) and penile (5%) cancers. Among patients with CAT, 11 (55%) had stage IV cancer, 4 (20%) had stage III, 2 (10%) had stage II, and 3 (15%) had stage I. High-grade tumours were predominant (75%) among patients with CAT. During the thrombotic event, 40% of patients were untreated, 40% received hormone therapy, and the remaining 20% underwent either systemic chemotherapy, systemic immunotherapy, intravesical chemotherapy, or intravesical Bacillus Calmette–Guérin. No significant association was found between CAT and comorbidities (Table 1). The presence of cardiovascular disease was associated with a higher but non-significant thrombosis rate (4.8% vs. 2.4%, p = 0.17). No significant association was found between CAT and the analysed risk factors (Table 2), with the presence of any cardiovascular disease risk factors showing similar thrombosis rates (3.7% vs. 3.0%, p = 0.879). Conclusions The prevalence of CAT in patients with genitourinary cancer was low, occurring mainly in advanced-stage, high-grade prostate cancer. CAT was equally distributed between arterial and venous beds, primarily affecting patients who were either untreated or receiving hormone therapy. Further studies with larger cohorts and extended follow-up are needed to define the potential associations between thrombotic events, cancer characteristics, and comorbidities in urological patients.