Arsenic trioxyde in the treatment of HTLV1 associated ATLL

Abstract

Background The prognosis of Adult T-cell leukemia/lymphoma (ATLL) associated with HTLV1 is dismal. The response to conventional chemotherapy ranges between 20 and 70% and relaspe is constant. Median survival is 8 to 13 months. Chronic and smouldering ATLL have a longer survival, ranging from 18 to 72 months at 5 years. Interferon alpha (IFNa) and AZT combination therapy is effective in acute, chronic and smouldering ATLL, sometimes leading to complete response and has a better prognosis than conventional chemotherapy (5 year survival of 82% in acute and 100% in chronic and smouldering forms reaching a complete response). Patients with ATLL/lymphoma do not benefit from IFNa+AZT combination and despite initial response to chemotherapy, all patients eventually relapse. Arsenic trioxyde (AsO3) in combination with IFNa has in vitro activity with a negative regulation of the Tax oncoprotein and leads to apoptosis of HTLV1 transformed lymphocytes. A recent study has showed a benefit in chronic forms of ATLL.