Haemolytic Anaemia in a Patient with Progressive Breast Cancer: Consider Thrombotic Microangiopathies and Treat the Cancer

Background: Haemolytic anaemia secondary to cancer is a rare and potentially fatal cancer complication belonging to the Thrombotic Microangiopathies (TMAs), which include the better known Thrombotic Thrombocytopenic Purpura (TTP) and Haemolytic-Uremic Syndrome (HUS). Making the diagnosis is important, as there is generally no response to classic TMA treatment, including plasma therapy, plasmapheresis, and rituximab. Yet, in current practice, diagnosis is often made late. Survival can be improved by administering chemotherapy early. Few cases have been described in the literature, and no other cases of TMA secondary to breast cancer with proof of response to a targeted treatment, such as everolimus combined with exemestane, have been reported. Case Presentation: A 76-year-old Caucasian woman with metastatic breast cancer was treated with aromatase inhibitors but presented with tumour progression and deterioration of her general condition. An evaluation revealed haemolytic anaemia with thrombocytopenia in combination with organ damage (brain and heart). She did not respond to classic TMA treatment, but to an antitumour treatment of exemestane combined with everolimus. Conclusion: This case demonstrates the need for and efficacy of a specific treatment for TMA secondary to cancer, as well as the efficacy of everolimus and exemestane in the management of TMA associated with progressive breast cancer