[Outcome of 126 adolescent and adult T-cell acute leukemia/lymphoma patients and the prognostic significance of early T-cell precursor leukemia subtype].

Objective: To evaluate the clinical characteristics of T-cell acute leukemia/lymphoma (T-ALL) and explore the prognosis significance of early T-cell precursor leukemia/lymphoma. Methods: A cohort of 126 patients diagnosed with T-ALL from 2008 to 2014 in West China Hospital, Sichuan University were enrolled in this study. They were further categorized by immunophenotype according to the expression of T-cell lineage markers CD1a, CD8, CD5 and one or more stem cell or myeloid markers. The laboratory indicators and prognosis factors were also statistically analyzed. Results: Of all patients, the ratio of male to female was 2.5∶1, with the median age of 25 years old (range 14 to 77) . The percentage of ETP-ALL was up to 47.6%. T-ALL patients showed higher ratio in first clinical remission rate (CR(1)) than T-LBL ones (64.4% vs 30.8%, P=0.032) . Group with WBC count higher than 50×10(9)/L at presentation showed higher ration of achieving CR(1) than those lower than 50×10(9)/L (78.4% vs 50.9%, P=0.010) . In comparison with the non-ETP-ALL, ETP-ALL patients had older age of onset (P<0.001) , lower WBC count (P<0.001) , lower risk of CNS involvement (10.0% vs 30.2%, P=0.009) and slightly inferior overall survival (P=0.073) . T-cell lineage markers CD1a(-), CD8(-) and CD4(-) positive patients had higher CR(1) than their corresponding negative ones (P=0.002, P=0.000, P=0.001) , while CD33(-) and CD56(-) positive patients had lower ratio of achieving CR(1) than their negative ones, respectively (P=0.035, P=0.035) . Conclusion: Flow cytometry and associated markers for immunophenotyping was of significance in the diagnosis and prognosis monitoring of T-ALL/LBL. The percentage of ETP-ALL/LBL subtype was high in Chinese adolescent and adult T-ALL patients. ETP-ALL/LBL was a high risk subtype, which needs more precise standard for diagnosis and advanced therapies for better outcome.