Abstract:

Case 1 is a 6-year-old boy, who was admitted to hospital in April, 2020 due to ??the left scrotal painless tumor found more than 1 year ago, with enlargement for16 d ''. The testicular tumor was removed by orchiectomy, and pathological examination suggested myeloid sarcoma, but the family members refused chemotherapy. Three months after the orchiectomy, the patient had fever and anemia. The bone marrow smears showed bone marrow necrosis. After 1 week of anti-infection treatment, bone marrow smears showed tumor cells while bone marrow biopsies suggested bone marrow metastasis of myeloid sarcoma. The patient had bone marrow remission after chemotherapy. Case 2 is a 11-year-old girl. She was admitted for ??weakness, poor appetite for 1 month, fever for 3 d'' in December 2012. Abdominal CT showed retroperitoneal malignant tumor with multiple bone metastasis. Bone marrow smear showed bone marrow necrosis. The diagnosis was neuroblastoma, and the patient was in remission after treatment. In May 2020, she was admitted for ??bone pain with fever for 3 d''. Bone marrow smear showed tumor recurrence. Anti-infection and chemotherapy were given, and bone marrow reexamination showed bone marrow necrosis. After aggressive anti-infection treatment, the bone marrow showed remission. She had hematopoietic stem cell transplantation, and now is on a post-transplant follow-up.The cause of bone marrow necrosis is complicated and malignant tumor is a common cause. For tumor cells, bone marrow biopsy can diagnose the disease more effectively than bone marrow smears. Prompt diagnosis and active treatment of the primary disease, which can cause bone marrow necrosis, can improve the prognosis.

Key words: bone marrow necrosis (BMN), bone marrow metastasis, bone marrow biopsy, malignant tumor