A 79-year-old woman was admitted with submandibular lymphadenopathy and was diagnosed as having bacterial and fungal lymphadenitis by lymph nodal biopsy. Laboratory examination demonstrated leukopenia with 7% blasts. The bone marrow was infiltrated with about 90% blasts and surface antigen analysis of these blasts demonstrated expression of cyCD3, TdT and MPO. The diagnosis was Mixed phenotype acute leukemia, T/myeloid, NOS. The patient was treated with prednisone (10 mg/day) for fever and subsequently CAM (800 mg/day) for pneumonia. Three months later, leukemic cells had disappeared on both bone marrow aspiration and peripheral blood smear. This clinical course suggests CAM is effective for this leukemia.