Summary

We report a case of concurrent thrombotic thrombocytopenic purpura (TTP) and immune thrombocytopenic purpura (ITP) in a 63-year-old woman who had been receiving treatment with bevacizumab for metastatic neuroendocrine tumour (NET). At diagnosis, she had severe anaemia and thrombocytopenia with elevated lactate dehydrogenase and many schistocytes on the peripheral blood smear. She was treated with frequent fresh frozen plasma infusions and plasmapheresis with poor response. Later, she was found to have platelet surface glycoprotein antibodies in the serum and received four cycles of rituximab, vincristine, cyclophosphamide (rituximab-CVP) and steroids in addition to plasma therapy. The haemoglobin and platelet counts improved. To our knowledge, this is the first reported case of concurrent TTP and ITP in a patient with metastatic NET diagnosed while receiving bevacizumab therapy, who was successfully treated with the combination of rituximab, vincristine, cyclophosphamide and steroids.