Remission from central nervous system involvement in adults with acute leukemia. Effect of intensive therapy and prognostic factors.

Eighty-seven adult patients who had achieved bone marrow remission of leukemia developed one or more episodes of meningeal leukemia. Multiple patient characteristics were examined for their effect on probability of achieving complete remission from meningeal disease and for their effect on duration of meningeal remission. Presence of obtundation (P less than 0.01) or other symptoms of meningeal disease (P = 0.02) were associated with a low remission induction rate. Other factors which tended (P = 0.06-0.20) to be associated with low remission induction rates included high cerebrospinal fluid (CSF) opening pressure, absence of splenomegaly at initial diagnosis, high peripheral blood leukocyte count (WBC) at the episode of marrow disease most recently preceding the meningeal disease, and use of only one as opposed to two or more intrathecal drugs as treatment. Factors associated with long duration of meningeal remissions included diagnosis (AML greater than acute undifferentiated leukemia greater than ALL, P = 0.05), absence of symptoms (P = 0.04), low CSF WBC (P = 0.01), rapid attainment of meningeal remission (P = 0.01), rapid attainment of initial bone marrow remission (P = 0.02), and long duration of initial bone marrow remission (P less than 0.01). Absence of cranial or peripheral neuropathies, low CSF protein and opening pressure, and short time interval between diagnosis of marrow and meningeal disease also tended (P = 0.06-0.20) to be associated with long meningeal remissions. Patients treated according to an intensive protocol utilizing cranial irradiation and triple drug treatment via an Ommaya reservoir had substantially longer meningeal remissions than did patients treated with less intensive therapy (P = 0.01). Relapse-free survival curves suggest that some patients are cured of their meningeal disease.