Long-term administration of a low-molecular-weight heparin contributed to successful treatment in a patient with primary mediastinal large B-cell lymphoma and venous thromboembolism.

The case of a 16-year-old girl with primary mediastinal large B-cell lymphoma who had thrombosis in the brachiocephalic, subclavian, and internal jugular veins at presentation is reported. MACOP-B chemotherapy plus radiation therapy could be the first-line strategy, but MACOP-B increases the risk of thrombosis. Although an effective method for initial treatment of venous thromboembolism (VTE) in cancer patients has not been established, recent studies revealed that the administration of a low-molecular-weight heparin (LMWH) was effective for secondary prevention of VTE. Therefore, the patient in this case was treated with MACOP-B plus rituximab followed by radiation therapy, and an LMWH was administered through the course of treatment. She achieved complete remission and never suffered from VTE. This case suggests that long-term administration of an LMWH contributes to the primary improvement and secondary prevention of VTE even in patients who are at high risk for thrombosis.