Precursor B-Cell Acute Lymphoblastic Leukemia With PICALM∶∶MLLT10 Fusion Gene Positivity:Report of One Case and Literature Review.

PICALM∶∶MLLT10 fusion gene-positive precursor B-cell acute lymphoblastic leukemia(pro-B-ALL)is clinically rare.This article reports the case of a 29-year-old female patient who presented a mediastinal mass.Diagnostic investigations confirmed PICALM∶∶MLLT10 fusion gene-positive pro-B-ALL.The patient sequentially received radiotherapy and multiple lines of chemotherapy but developed short-term drug resistance and lineage change,progressing to mixed-phenotype acute leukemia.A review of relevant literature was conducted to analyze its pathogenesis and molecular characteristics,aiming to provide references for clinical diagnosis and treatment.