Figure 1 Time course of PLT count over the clinical course of the patient. Following a diagnosis of ITP, the patient initially received IVIG and steroid therapy. As the disease was refractory to the initial treatment, splenectomy was performed, resulting in a transient increase in PLT count. She was subsequently diagnosed with HS and underwent CHOEP chemotherapy. Despite the initial treatment response, the disease relapsed and the platelet count declined again. She then received high-dose chemotherapy followed by auto-SCT. However, BM relapse was detected, and she was treated with ICE salvage chemotherapy. PLT – platelet; ITP – immune thrombocytopenia; IVIG – intravenous immunoglobulin; HS – histiocytic sarcoma; CHOEP – cyclophosphamide, doxorubicin, vincristine, etoposide, and prednisone; SCT – stem cell transplantation; BM – bone marrow; CR – complete remission; PR – partial response; ICE – ifosfamide, carboplatin, and etoposide.