The prognosis of
non-Hodgkin's lymphoma (NHL) in childhood has improved steadily in the last 2 decades. This is primarily the result of increasingly effective
chemotherapy regimens tailored to defined and relatively homogeneous prognostic categories and tested in prospective clinical trials. Surgical excision remains of prognostic benefit only when near-total resection can be performed without delay of
chemotherapy. The role of
radiation therapy is now limited to the treatment of overt central nervous system (CNS)
lymphoma, disease unresponsive to
chemotherapy, and certain emergencies. Effective 'prophylactic' treatment of the CNS has been achieved in most series by intrathecal and systemic
chemotherapy alone. The most relevant modality of treatment is
chemotherapy and a very large number of protocols have been published. The origins of current multi-agent regimens stem both from early experience with
cyclophosphamide in endemic
Burkitt's lymphoma and from therapeutic studies of acute lymphoblastic leukaemia. Sub-stratification of non-localized NHL has produced protocols designed for either lymphoblastic (mostly T cell) or non-lymphoblastic (mostly B cell) categories. While the cure rate for
lymphoblastic lymphoma now exceed 70%, the non-localized non-lymphoblastic disease remains a major obstacle to cure. These patients frequently present with large abdominal primaries and are prone to regional as well as hematogenous dissemination. In particular, involvement of the CNS is now considered to be the most adverse prognostic variable in this group. Recently, highly intensive regimens are addressing these obstacles. On the other hand, NHL defined as localized has been shown to be curable in up to 95% of children with the use of simple
chemotherapy regimens as short
as 6 months in duration. Salvage of patients who relapse during or after
chemotherapy remains bleak but cures are possible with regimens incorporating
bone marrow transplantation from either an autologous or allogeneic source. Experimental methods, including
biologic and immune response modifiers may also offer future promise.