Pb2294: dose-adjusted edoch as first-line therapy improved prognosis of adult t-cell leukemia/lymphoma: a 11-year multicenter retrospective study in china

Topic: 19. Aggressive Non-Hodgkin lymphoma - Clinical Background: Adult T-cell leukemia/lymphoma (ATLL) is a rare malignancy of mature CD4(+) T-cells caused by human T-cell lymphotropic virus-1 (HTLV-1) with poor prognosis. There is no widely accepted standard treatment for aggressive ATLL, although doxorubicin-based chemotherapy remains the most common treatment. Much of the clinical data on ATLL derived from Japanese population and little was published about Chinese. Aims: This multi-center study aimed to analyze the clinical characteristics and prognosis based on different treatment regimens of ATLL in China. Methods: We retrospectively analyzed the clinical characteristics and prognosis based on different treatment regimens of 102 patients diagnosed with ATLL between June 2011 and December 2022 from 4 hospitals in Fujian provinces. Results: All of 102 patients came from coastal cities of Fujian province where a HTLV-1 epidemic area locates. 58 patients (56.9%) were male and 44 patients (43.1%) were female. The median age at diagnosis for all patients was 52 (range 23-80) years old. Among the 102 patients, 93 patients (91.2%) were confirmedly diagnosed as ATLL through HTLV-1 provirus genes detection by PCR and the diagnosis of other 9 cases were made based on seropositivity for HTLV-1. In the subtype classification of these 102 ATLL, 68 patients were classified as acute type and 34 cases as lymphoma type ATLL. 88 out of 102 patients underwent bone marrow aspiration, and “flower-like”, with typical or atypical morphology had been observed in a high rate (65/88, 73.9%). Elevated LDH was noted commonly (87/98, 88.8%), data were missing for 4 cases. Serum LDH elevated (P=0.003), bone marrow involvement (P<0.001), liver infiltration (P=0.012) were associated with acute ATLL. Most of the ATLL cells exhibited a typical immunophenotype with CD4+ CD8- (80.5%). Confection of hepatitis B virus was detected in 28 patients (28.9%). 81 patients received chemotherapy, the overall response rate (ORR) rates for lymphoma (n=30) and acute (n=51) after first-line chemotherapy alone was 77% (complete response [CR] 57%) vs 42% (CR 19%), respectively, of which 8 cases in complete remission after chemotherapy received hematopoietic stem cell transplantation (HSCT) (allo-HSCT: n=6; auto-HSCT: n=2) and 3 cases received salvage allo-HSCT during disease progression. At the end of the follow-up, 48 cases died, 54 cases survived, the 1-year and 3-year overall survival (OS) rate were 32.4% and 28.2%, respectively, and the median survival was 8 months. The 3-year survival rates (the median survival time, days) for acute and lymphoma type ATLL were 20.2% (66) and 40.3% (363), respectively (P＜0.0001). The ORR rates after the first-line multiagent chemotherapy using etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin (EDOCH) regimen (n=50, including 32 cases with dose-adjusted EDOCH) and other regimens (n=31) were 70% (CR 46%) vs 30% (CR 11%), respectively. The 3-year survival rates (the median survival time, days) for EDOCH regimen (n=39), HSCT post EDOCH regimen (n=11) and other regimens (n=31) were 38.5% (453), 45.7% (333) and 0% (68), respectively (P=0.0025). Leukocytosis (P<0.0001), lymphocytosis (P<0.0001), hypoalbuminemia (P=0.023), serum LDH elevated (P=0.044) and hypercalcemia (P=0.015) were associated with poor prognosis. Summary/Conclusion: These data demonstrate characteristics of those ATLL encountered in the coastal area of Fujian province are typical and prognosis is unsatisfactory, especially for the acute type. Initial treatment with EDOCH regimens showed superior ORR and OS compared to the other regimen for patients with aggressive ATLL, up-front allo-HSCT should be considered for all suitable patients with aggressive ATLL. Keywords: Prognosis, ATL, Clinical data