Abstract Out of 153 newly referred human T-lymphotropic virus type I infected patients 42 (27%) had ≥5% abnormal lymphocytes, consistent with the diagnosis of smouldering adult T-cell leukaemia/lymphoma. The abnormal lymphocyte percentage was higher in patients with human T-lymphotropic virus type I associated inflammatory disease compared with asymptomatic carriers (p=0.006). Over 4.5 years
... [Show full abstract] median follow up four patients, all with ≥10 human T-lymphotropic virus type I DNA copies/100 peripheral blood mononuclear cells at presentation, but only one with ≥5% abnormal lymphocytes at presentation, developed adult T-cell leukaemia/lymphoma. Thus high pre-morbid human T-lymphotropic virus type I proviral load, rather than fulfilment of the classification criteria for smouldering adult T-cell leukaemia/lymphoma, was associated with an increased risk of developing aggressive adult T-cell leukaemia/lymphoma.