A Case of Therapy-Related Acute Myeloid Leukemia Associated with Adjuvant Temozolomide Chemotherapy for Anaplastic Astrocytoma

Background Temozolomide (TMZ) is now standard adjuvant therapy in combination with radiotherapy for patients with newly diagnosed malignant glioma. Treatment-related myelodysplastic syndrome and acute treatment-related leukemia (t-AML) associated with TMZ chemotherapy for patients with glioma is quite a rare complication. Case Description A 43-year-old man with an anaplastic astrocytoma received radiation therapy synchronized with ranimustine and adjuvant TMZ chemotherapy for 15 cycles. Close follow-up magnetic resonance imaging of the head during TMZ chemotherapy showed no evidence of tumor progression. One year after the completion of TMZ chemotherapy, a bone-marrow aspiration was performed because the patient's white blood cell count decreased. He was diagnosed with t-AML based on the bone marrow examination, and then he was referred to the cancer center for the treatment of t-AML. Conclusions In this case study, we continued adjuvant TMZ therapy beyond the recommended 6 cycles. Currently, there is no consensus as to how long the adjuvant TMZ therapy should be continued for the treatment of residual tumor showing no apparent interval change. A new decision-making tool to assess the clinical benefits against the side effects for long-term adjuvant TMZ therapy is needed.