Recent well-designed, prospective, controlled trials have demonstrated a lower incidence of catheter-related deep vein thrombosis (CRDVT) compared with earlier studies but this complication remains an important limitation to the delivery of drugs and supportive care to cancer patients. Prophylaxis of CRDVT with antithrombotic agents was not supported by recent prospective randomized trials, and its routine use is not recommended. Larger studies will be required to determine if cancer patients at particularly high risk for CRDVT can benefit from prophylaxis with antithrombotic agents. There are no prospective controlled studies to guide the therapy of CRDVT but treatment with anticoagulants remains the mainstay of therapy. Although recently published guidelines might help standardize the therapy of patients with CRDVT, prospective controlled studies are needed to determine the optimal therapy of this important complication of central venous catheters in cancer patients.