T-cell acute lymphoblastic leukaemia in adults.

Of 27 consecutive adult patients with acute lymphoblastic leukaemia (ALL), 7 had T-cell variants on the basis of sheep erythrocyte (E) rosette formation; in 5, a characteristic thymic phenotype was demonstrated by the use of appropriate monoclonal antibodies. All patients were treated with prednisone, vincristine, 1-asparaginase and adriamycin and the peripheral blood cleared of circulating lymphoblasts in a median of 8 days (range 6 - 45 days), a figure which does not differ significantly from that of 7 days (range 3 - 59 days) in those with the common ALL (P greater than 0,5). The complete remission rates were 71% for the patients with T-cell leukaemia and 75% for the E rosette-negative patients; median durations of remission were 35 and 26 weeks respectively and the actuarially predicted median durations of survival were 49 and 39 weeks respectively. Therefore the presence of T-cell markers in adult ALL does not seem to affect the prognosis in the same way that it does in children, and this is likely to be the result of the more aggressive clinical course of ALL of all phenotypes in adults.