PB1806 TREATMENT OF RELAPSED AND REFRACTORY T‐CELL LYMPHOMAS: FIRST PAVLOV STATE MEDICAL UNIVERSITY OF SAINT‐PETERSBURG EXPERIENCE

Background:T‐cell lymphomas represent rare and heterogeneous group of aggressive non Hodgkin lymphomas. There are currently no standards for the treatment of relapsed/refractory T‐cell lymphomas (r/r PTCL). A number of novel therapy approaches are aimed for improvement of outcomes in patients with r/r PTCL.Aims:This report summarizes the First Pavlov State medical University experience in the treatment of patients with T‐cell lymphomas.Methods:We analyzed data of 34 patients with r/r PTCL eligible for stem cells transplantation treated in First Saint‐Petersburg state medical University from 2005 to 2018. Among them n8 with anaplastic large cell lymphoma (ALK+), n3 with anaplastic large cell lymphoma (ALK‐), n4 with angioimmunoblastic T‐cell lymphoma, n5 with hepatosplenic T‐cell lymphoma, n1 with γδ T cell lymphoma and n13 with PTCL not otherwise specified (PTCL‐NOS). The median age was 46 years (range 11 – 73 years).Median time from initial diagnosis to relapse or progression after primary therapy was 6.7 months (1,8‐41). Among all patients n18 (53%) had a primary chemoresistant disease, while the rest n14 (47%) had a relapse after initial treatment. All patients received at least one line of salvage chemotherapy. The treatment was tailored according to biological factors presented in patients. In 7 patients with CD30+ PTCL the brentuximab vedotine was used. One patient with ALK+ anaplastic lymphoma received ALK inhibitor crizotinib. One patient with γδ TCL and PD‐L1 hyperexpression was treatment with nivolumab. Responses were consolidated with hematopoietic stem cells transplantation. Overall 16 patients undergo SCT: high dose chemotherapy with autologous stem cells transplantation was performed in 10 patients, 11 patients underwent allogeneic hematopoietic stem cells transplantation (among them 5 patients with relapses after auto‐SCT).Results:At the time of analysis, 25 patients remain alive. The median follow up of alive patients was 29 months (1,5‐101 mo). The median overall survival was not reached and 2‐year survival rate was 82%. The disease status at the last follow up was CR in 15 patients, PR in 3 patients and PD in 16. Among factors significantly associated with adverse prognosis was lower ECOG performance status at the time of diagnosis (p = 0,03). Patients that had underwent salvage SCT showed significantly better disease status at the moment of last follow up: 12/16 (75%) were in CR, versus 3/18 (17%) in patients who did not undergo SCT. No difference was found in OS between relapsed and primary refractory patients (p = 0,73).Summary/Conclusion:The results of analysis show that introduction of novel agents and consolidation with high dose chemotherapy and autologous stem cells transplantation or allogeneic stem cells transplantation in selected cases may improve outcomes in patients with relapsed and refractory peripheral T‐cell lymphomas. Brentuximab vedotine based regimens may be successfully used as a bridge therapy before stem cells transplantation.