Angioimmunoblastic T-Cell Lymphoma: A Large Series Outcome Analysis.
Authors: Kyriakou Charalampia , Attygalle Ayoma , Linch David , Goldstone Anthony , Smith Paul , Dogan Ahmet 
Published: April 2020

Abstract
Angioimmunoblastic T-cell Lymphoma (AITL) is a rare Peripheral T-cell lymphoma that primarily affects the elderly, presenting as advanced disease characterized by aggressive behaviour and very poor outcome. Despite the unfavourable prognosis, the best approach for treating patients with AITL is still unknown. We report a retrospective multicentre study of 64 AITL patients (37 male, 27 female) who were diagnosed as AITL in our institution based on typical histology and molecular clonality analysis between 1995 and 2004. The median age at diagnosis was 60 years (range 25 to 87). Fifty-two patients (81%) presented with advanced stage III–IV disease, 41 (64%) had B symptoms and 49 (76%) elevated LDH. ECOG performance status was 1 for 40%, 2 for 53% and 3 for 9% of the patients. Based on IPI risk factors 12% of the patients were classified as low risk, 17% low intermediate, 29% high intermediate and 42% as high risk. Six patients developed autoimmune haemolytic anaemia. Therapeutic approach varied from no treatment to high dose therapy (HDT). The majority of the patients had received CHOP chemotherapy. Overall 19 patients (30%) had received 1 treatment line, 20 (31%) had 2, 19 (30%) 3, 4 patients (6%) were treated with ≥4 and 2 (3%) were not eligible for any treatment. Twenty patients (31%) proceeded to an autologous and 2 to allogeneic transplantation after achieving CR (n=12), PR (n=7) while 3 had progressive disease. Following first line therapy 37 patients (58%) achieved CR, 15 (23%) PR and 10 (16%) had primary refractory disease. Median time to relapse or progression was 6 months (1 to 89). Interestingly three patients relapsed as EBV driven DLBCL, 1as DLBCL and 2 as EBV driven Hodgkin’s lymphoma. With a median follow-up of 19 months (1 to 119) twenty-six patients (41%) were alive. Eighteen (28%) of these patients were in CR, and 8 in PR (13%). Thirty-seven patients (58%) died, 29 (45%) from disease progression. Twelve patients developed toxic complications -infectious complications (n=8), haemorrhage (n=1), thrombosis (n=1) myocardial infarction (n=2). The estimated PFS rates at 1 and 2 years were 33% and 27% respectively. Overall survival rates were estimated at 55% and 28% at 2 and 4 years. By univariate and multivariate analyses, no response to first line therapy (p=0.035) and male sex (p=0.0161), were significantly associated with higher relapse rate. Application of HDT resulted to significantly superior PFS (p=0.002). Poor performance status at presentation was the only factor found to be significant for the OS (p= 0.0317). In conclusion analysis of the results of this large cohort of AITL patients showed that although the initial overall response rate was 73% this was short lived. It is estimated that less than 30% of the patients will survive and remain disease free at 4 years. Considering the dismal outcome with current therapeutic approaches, new strategies using novel agents to improve further and most importantly maintain initial response are needed. The role of frontline HDT either autologous or allogeneic for eligible AITL patients is worth exploring in prospective collaborative studies.