In a registry-based study reported in the Journal of Clinical Oncology, Galanaud et al found that outcomes in patients with cancer-associated isolated distal deep-vein thrombosis (DVT) were similar to those in patients with cancer-associated proximal DVT.
The study included data from the international Registro Informatizado de la Enfermedad TromboEmbolica venosa registry (REITE registry), which included data from sites in 28 countries in Africa, North and South America, Asia, and Europe on patients with DVT enrolled between March 2001 and August 2022 who had completed ≥ 90 days of follow-up. The study included data on 886 patients with cancer-associated distal DVT; 5,196 with cancer-associated proximal DVT; and 5,974 with non–cancer-associated distal DVT.
Over 90% of patients in each group received anticoagulant therapy for ≥ 90 days. At 90 days, compared with patients with cancer-associated distal DVT, those with non–cancer-associated distal DVT had lower risks of death (adjusted odds ratio [aOR] = 0.16, 95% confidence interval [CI] = 0.11–0.22), venous thromboembolism (VTE) recurrence (aOR = 0.34, 95% CI = 0.22–0.54), and major bleeding (aOR = 0.47, 95% CI = 0.27–0.80). Differences in risks for these outcomes were similar at 1-year follow-up, with respective adjusted hazard ratios of 0.12 (95% CI = 0.09–0.15), 0.39 (95% CI = 0.28–0.55), and 0.51 (95% CI = 0.32–0.82).
At 90 days, for cancer-associated proximal vs distal DVT, no significant differences were observed in risk for death (aOR = 1.11, 95% CI = 0.91–1.36), VTE recurrence (aOR = 1.10, 95% CI = 0.76–1.62), or major bleeding (aOR = 1.18, 95% CI = 0.76–1.83). Risks for these outcomes also did not differ at 1 year, with respective adjusted hazard ratios of 1.01 (95% CI = 0.89–1.15), 1.02 (95% CI = 0.76–1.35), and 1.10 (95% CI = 0.76–1.61). Patients with cancer-associated proximal vs distal DVT had a higher 1-year rate of fatal pulmonary embolism (23 patients vs 0 patients; absolute risk increase = 0.40%, 95% CI = 0.23%–0.58%).
The investigators concluded, “Cancer-associated distal DVT has serious and relatively comparable outcomes compared with cancer-associated proximal DVT. The lower risk of fatal pulmonary embolism from cancer-associated distal DVT needs further investigation.”
Jean-Philippe Galanaud, MD, of the Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by Sanofi-Aventis, Rovi, and others. For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.