Outcome of adult T-lymphoblastic lymphoma depends on ALL-type chemotherapy, prognostic factors, and performance of allogeneic hematopoietic stem cell transplantation

To study the prognostic factors of adult patients with T-lymphoblastic lymphoma (T-LBL) and to evaluate therapeutic effects of acute lymphoblastic leukemia (ALL)-type chemotherapy in combination with allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients who achieved overall response (OR) with first line ALL-type chemotherapy. This was a retrospective study of 59 adult patients with T-LBL treated with hyper-fractionated administration of cyclophosphamide, vincristine, doxorubicin and dexamethasone/methotrexate (hyper-CVAD/MA) chemotherapy alone or in combination with allo-HSCT between June 2008 and October 2015. Complete response (CR) and OR rates were evaluated after the initial chemotherapy. Clinical characteristics and the risk factors associated with prognosis and overall survival (OS) were analyzed in all patients and the effects of allo-HSCT on OS were evaluated in patients who had achieved OR after initial chemotherapy. Forty-eight patients (81.4%) achieved OR by hyper-CVAD chemotherapy, among which, 22 patients (45.8%) further received allo-HSCT. The median follow-up was 31.5 months, ranging from 11 to 97 months. The 3-year OS and progression-free survival (PFS) were 45.7% and 45.0% for patients who achieved OR after chemotherapy and both 0 for patients who did not achieve OR (both P < .001). Three year OS and PFS were higher in patients who received chemotherapy + allo-HSCT than in patients who received chemotherapy alone (3-year OS: 72.8% vs 17.5%, P = .008; PFS: 65.1% vs 27.8%, P = 0.007). Shorter survival was independently associated with elevated lactic dehydrogenase (LDH), Ki-67≥75%, pleural effusion and no OR (all P < .05) in all patients. But shorter survival was only associated with elevated LDH level, leukocytosis (>10 G/L), and chemotherapy alone in patients who achieved OR (all P < .05). The mid-term outcomes of adult patients with T-LBL are associated with response to chemotherapy (in all patients) and performance of allo-HSCT (in patients who achieved OR). Allo-HSCT could be a feasible and effective consolidation therapy for adult T-LBL.