"Smouldering" and symptomatic forms of central nervous system involvement in the course of non-Hodgkin's lymphoma in children.

34 children with Non-Hodgkin's lymphoma (NHL) were treated with LSA2L2 protocol from 1978 to 1981. In 12 cases (31.4%) the central nervous system (CNS) was involved, including 3 cases at the onset of the disease. CNS involvement was always diagnosed by the presence of blast cells in cerebro-spinal fluid, also in cases with normal pleocytosis and no neurological symptoms. Such cases were called "smouldering" CNS involvement. Four children had a smouldering form of CNS involvement. 3 of them are in continuous complete remission with cessation of therapy, while all those 6 patients with symptomatic CNS involvement died. "Smouldering" CNS involvement seems to have a better prognosis than the symptomatic one.