Diagnosing and treating mixed phenotype acute leukemia: a multicenter 10-year experience in México

Mixed phenotype acute leukemia (MPAL) in adults represents nearly 2 to 5 % of all acute leukemia cases. There are two large studies throughout the world and only case reports and small series have been reported in Latin America. This study retrospectively analyses the clinical characteristics and survival of 27 patients with MPAL evaluated in three medical institutions of Mexico. All cases meet World Health Organization 2008 criteria; 70.3 % of patients had B lymphoid/myeloid lineage MPAL. Induction chemotherapy protocols included 7 + 3 hyper-CVAD, high-density schedules, and pediatric-like regimens such as New York II and total XI. Complete remission was achieved in 23/27 patients (85.2 %). Only one patient died due to chemotherapy-induced aplasia during remission induction (5.2 %). In 68 % of cases, we were able to administer maintenance therapy as a regimen in lymphoblastic leukemia. At the time of analysis, 70.4 % of the patients in the entire cohort had died mainly as result of disease progression (73.6 %). Disease-free survival was 13 months (95 % CI, 9.6-16.3 months) and overall survival was 14.8 months (95 % CI 13.4-16.27). Survival rates are low and standardized therapy for the management of this type of leukemia is still lacking. This is the largest series reported in Mexico and to the best of our knowledge in Latin America.