[Characteristics and prognosis in adult patients with early T-cell precursor acute lymphoblastic leukemia]

Objective: To analyze the clinical, laboratory characteristics and prognosis of adult early T-cell precursor acute lymphoblastic leukemia (ETP-ALL). Methods: The clinical data of 13 adult ETP-ALL patients from January 2009 to March 2017 were retrospectively analyzed and compared with non-ETP ALL patients. Results: 13 ETP-ALL patients (17.3%) were identified in 75 adult T-ALL patients, the median age of the patients was 35 years old (15 to 49 years) and 10 patients were male (76.9%). ETP-ALL patients had lower WBC count, LDH level, blasts in peripheral blood, lower incidence of thymic mass and higher PLT count compared to non-ETP ALL patients. The CR rate after one course induction chemotherapy for ETP-ALL and non-ETP ALL patients was 33.3% and 90.1%, respectively (χ(2)=26.521, P<0.001). The median overall survival(OS) was 11.33 (95%CI 0-28.46) and 25.69 (95%CI 11.98-39.41) months, respectively. The 3-year OS was 41.7% and 40.7%, respectively (P=0.699). The median event free survival (EFS) was 1.51 (95%CI 1.23-1.79) and 21.36 (95%CI 4.67-38.04) months, respectively. The 3-year EFS was 16.7% and 39.5%, respectively (P=0.002). The 3-year relapse free survival (RFS) was 53.0% and 52.0%, respectively (P=0.797). Multivariate analysis revealed that CNSL and allo-HSCT were independent risk factors affecting OS of T-ALL and ETP-ALL didn't affect the prognosis of T-ALL. Conclusion: To our knowledge, this study is the first report on characteristics and prognosis of adult ETP-ALL patients in China. At total of 13 T-ALL patients (17.3%) were classified as having ETP-ALL. These patients had a lower leukemia burden and lower CR rate after one course induction compared to non-ETP ALL patients. Allo-HSCT can improve the prognosis of ETP-ALL.