Ami Schattner and Natasha Kozack report a case of mesothelioma in a man who exhibited jugular and subclavian vein thrombosis.1 Malignant pleural mesothelioma is a relatively rare type of cancer that is reported to be associated with venous thromboembolism.2 We describe here a patient with malignant pleural and peritoneal mesothelioma who experienced portal vein thrombosis. This patient had a history of exposure to zeolite, and ascites developed while the patient was being followed for the malignant pleural mesothelioma.
CT of the abdomen revealed diaphragmatic invasion of the right pleural mesothelioma. In addition to the peritoneum, the omentum and mesentery were diffusely invaded by the tumour. At the same level, the portal vein and the inferior vena cava both appeared to have a lucent lumen and exhibited contrast enhancement at the vessel wall (Fig. 1).
Cancer patients are prone to thromboembolic events, either as part of a paraneoplastic syndrome or because of a decrease in anticoagulation factors, such as prothrombin C, prothrombin S and antithrombin III, caused by some chemotherapeutic agents.3 Mesothelioma cells and cell lines have been shown to secrete a pleiotropic cytokine, interleukin 6, which potentiates the production of platelets.4 In addition, mesothelioma cells release a sedimentable procoagulant material in vitro;5 however, the underlying mechanism of thrombosis in mesothelioma is still a mystery.
Physicians who care for patients with mesothelioma should keep in mind that the thrombotic complication of the disease is not rare and may also involve a relatively unusual site, the portal system.
Mehlika Isildak Gulay Sain Guven Department of Internal Medicine Salih Emri Department of Respiratory Medicine Hacettepe University Faculty of Medicine Ankara, Turkey