Mixed phenotype acute leukemia: Biological profile, clinical characteristic and treatment outcomes: Report of the population‐based study

• Published in: European journal of haematology Vol. 105; no. 1; pp. 85 - 93
• Main Authors: Zając‐Spychała, Olga, Irga‐Jaworska, Ninela, Drożyńska, Elżbieta, Muszyńska‐Rosłan, Katarzyna, Krawczuk‐Rybak, Maryna, Zawitkowska, Joanna, Kowalczyk, Jerzy, Ćwiklińska, Magdalena, Balwierz, Walentyna, Mizia‐Malarz, Agnieszka, Badowska, Wanda, Kamieńska, Elżbieta, Urasiński, Tomasz, Kaczorowska, Aneta, Kazanowska, Bernarda, Chybicka, Alicja, Wysocki, Mariusz, Sędek, Łukasz, Szczepański, Tomasz, Woszczyk, Mariola, Matysiak, Michał, Młynarski, Wojciech, Karolczyk, Grażyna, Chaber, Radosław, Wachowiak, Jacek
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01-07-2020
• Subjects: Acute myeloid leukemia; Chemotherapy; Children; Cytogenetics; diagnosis; hematopoietic stem cell transplantation; Leukemia; Medical prognosis; mixed phenotype acute leukemia; Oncology; Patients; Phenotypes; Population studies; Population-based studies; prognosis; Stem cell transplantation; hematopoietic stem cell transplantation; diagnosis; mixed phenotype acute leukemia; chemotherapy; prognosis
• ISSN: 0902-4441; 1600-0609
• DOI: 10.1111/ejh.13413

Objectives
The aim of this population‐based, retrospective study was to analyze biological and clinical features and treatment results in children diagnosed with MPAL in all Polish pediatric oncology centers between 2007 and 2018.
Methods
Among 2893 children and adolescents diagnosed and treated for acute leukemia, 39 (1.35%) patients fulfilled the WHO criteria of MPAL. The T/myeloid phenotype was most prevalent.
Results
Cytogenetics findings were seen in 2 (5.1%), while chromosomal abnormalities were found in 14 (35.9%) patients. Thirty‐two patients achieved CR‐1, including 23 (92.0%) treated with ALL‐directed chemotherapy and 9 (64.3%) treated with AML‐type induction regimens. Within these patients, 4 (12.5%) died due to treatment‐related complications and 11 (34.4%) relapsed. Nineteen (63.3%) patients underwent allo‐HSCT in CR‐1 and 14 (73.7%) of them have been in CR‐1. In total, 17 (43.6%) patients remain in CR‐1 for 1‐12 years, including 14 (58.3%) with T/myeloid MPAL. The 5‐year pOS and pEFS were 51.8% and 44.2%, respectively. The overall survival for ALL‐directed therapy was significantly better than the one for AML‐type chemotherapy (P = .001). It was also better for patients who underwent HSCT in CR‐1 (P = .001).
Conclusions
The prognosis of MPAL is unsatisfactory, but initial treatment with ALL‐directed chemotherapy consolidated with allo‐HSCT improves the outcomes in MPAL.