Distal and proximal deep venous thrombosis were associated with similar outcomes in patients with cancer.

Patients without cancer who develop distal deep venous thrombosis (DVT) of the leg (i.e., calf DVT) have lower risk for developing recurrent venous thromboembolism (VTE) than do patients with proximal DVT; whether the same is true for patients with cancer is unclear. Researchers used a 10-year international cohort of 110,000 patients with new DVTs to compare outcomes among patients with active cancer who developed distal DVT, patients with cancer who developed proximal DVT, and patients without cancer who developed distal DVT. Nearly all patients in each group received anticoagulation for at least 3 months, and outcomes were assessed at 3 and 12 months.

In patients with active cancer, three adverse outcomes — all-cause mortality, VTE recurrence, and major bleeding — were not significantly different in patients with distal DVT and in those with proximal DVT. However, patients without cancer who had distal DVT had adverse outcomes significantly less commonly than did patients with cancer who had distal DVT (all adjusted odds ratios and adjusted hazard ratios for the 3 outcomes, ≤0.5).

COMMENT
This study demonstrates that distal DVT in patients with cancer is associated with worse outcomes than in patients without cancer. The other key finding — similar incidences of adverse outcomes following distal DVT and proximal DVT in patients with cancer — suggests that distal DVT should not be considered a less-serious complication in this patient population. — Daniel D. Dressler, MD, MSc, MHM, FACP

Dr. Dressler is Professor of Medicine at Emory University School of Medicine, Atlanta.

Galanaud J-P et al. Clinical presentation and outcomes of patients with cancer-associated isolated distal deep vein thrombosis. J Clin Oncol 2024 Feb 10; 42:529. (https://doi.org/10.1200/JCO.23.00429)

GKB-NON-2024-00211