Atypical Evolution of Secondary Hemolytic Uremic Syndrome Defined as Paraneoplastic Syndrome under Eculizumab and Palbociclib Therapies

Thrombotic microangiopathy (TMA) is most of the time caused by thrombotic thrombocytopenic purpura or hemolytic uremic syndrome. A 60-year-old female was diagnosed in 2014 with mammary breast adenocarcinoma treated by several-line therapy: mastectomy, docetaxel, cyclophosphamide, radiotherapy, doxorubicine, and capecitabine. By mid-November, the patient was admitted to the hospital with regenerative, mechanical, and hemolytic anemia, schistocytes at 3%, and thrombopenia (99 G/L), associated with high blood transfusion requirement. After 9 sessions of plasmapheresis, there was no significant improvement in the biological parameters, nor after 2 cycles of paclitaxel. The patient was then treated with eculizumab during 4 weeks, with a slight reduction in blood requirement, and simultaneously with palbociclib. Since being treated with palpociclib, she had a great reduction in blood requirement and a good clinical condition. To conclude, we reported an initial moderate improvement of paraneoplasm-related TMA syndrome under eculizumab therapy with a slight reduction in red blood cell requirement; however, palbociclib therapy achieved a very good response with a dramatic reduction in red blood cell requirement.