Objective: To evaluate the safety and efficacy of mitoxantrone liposome (MIT-LIP) combined chemotherapy in treating mixed phenotype acute leukemia (MPAL) . Methods: December 2021 to November 2024, MPAL patients who underwent the MAED (MIT-LIP + cytarabine + etoposide + dexamethasone) regimen were retrospectively analyzed. Data on clinical characteristics, adverse reactions, therapeutic outcomes, and long-term prognoses were collected. Results: A total of 7 MPAL patients who received MAED regimen were admitted. Among them, two patients were initially diagnosed with T-ALL or B-ALL, respectively, and transformed into AML after treatment. Three patients were initially diagnosed as MPAL (B/myeloid), one as MPAL (T/myeloid), and one with MPAL (myeloid/plasmacytoid dendritic cell). Among the 7 patients, there were 3 males and 4 females, 1 chromosome abnormalities and 6 gene abnormalities, including 1 case with BCR∷ABL fusion gene. The median age was 38 years (range: 16-58 years). There was no clear related drug allergy and organ toxicity during MAED regimen, and the main adverse effect was hematological toxicity. After induced chemotherapy, all patients achieved complete remission (CR), 2 maintained MRD-negative CR and 1 maintained MRD-positive CR. The other 4 patients underwent allogeneic hematopoietic stem cell transplantation, 2 maintained MRD-negative CR, and 2 relapsed. The current median follow-up time was 12 months, the overall survival (OS) rate was 100%, the relapse-free survival (RFS) rate was 60%, and the median OS time and median RFS time were not reached. Conclusion: The MAED regimen demonstrates high safety and a favorable CR rate in MPAL treatment.

Mixed-phenotype acute leukemia (MPAL) is characterized by acute undifferentiated leukemia with blasts co-expressing myeloid and lymphoid antigens. However, consensus regarding the ideal management strategy for MPAL is yet to be established, owing to its rarity.

A 55-year-old male was diagnosed with T/myeloid MPAL. Vincristine, prednisolone, daunorubicin, and L-asparaginase were administered as induction chemotherapy. Septic shock occurred 10 days after induction, and bone marrow examination following recovery from sepsis revealed refractory disease. Venetoclax and decitabine were administered as chemotherapy-free induction therapy to reduce the infection risk. There were no serious infections, including febrile neutropenia, at the end of the treatment. After receiving two additional cycles of venetoclax/decitabine, the patient underwent haploidentical peripheral blood stem-cell transplantation and achieved complete response (CR) to treatment.

CR was maintained in a patient with MPAL who underwent haploidentical peripheral blood stem-cell transplantation after additional venetoclax/decitabine cycles.