Skin necrosis in the forefoot during anticoagulation with phenprocoumon

History and admission findings: A 52-year-old woman was admitted because of pain for several days in the lower left leg and increasing pretibial swell ing with livid discoloration. Six months before she had undergone a bilater al adnexectomy with removal of the omentum and subsequent chemotherapy for ovarian cancer. Investigations: Duplex sonography on the day of admission revealed thrombos is of the left popliteal vein with an unobstructed femoral vein. Both the q uick value (89%) and partial thromboplastin time (PTT, 35.9 s) were within normal limits. Computed tomography and sonography were highly suspicious of a local recurrence of the ovarian cancer with peritoneal carcinomatosis. Treatment and course: PTT-effective heparinization (heparin-Na) was initiat ed together with overlapping anticoagulation with phenprocoumon (thrombopla stin time 20-30%). On the 9(th) day after starting phenprocoumon painful, b lack necrotic changes began to appear on the skin of the left first to four th toes. Assuming these to be due to phenprocoumon, anticoagulation was swi tched to low-molecular heparin (Enoxaparin), and antithrombin III and prote in C were administered. A few days later thrombosis of the right iliac vein occurred, probably caused by local recurrence of the ovarian cancer. No pa lliative chemotherapy was undertaken in view of the thrombotic complication s. The patient died a few months later from the cancer. Conclusion: If there is an underlying malignancy, chemotherapy and therapeu tic vitamin-K antagonism in the presence of thromboembolic complications in creases the risk of lowering protein C activity and may cause the rare comp lication of skin necrosis,induced by phenprocoumon.