Recognized classification scheme for non-Hodgkin's lymphoma in childhood and adolescence, St. Jude's modification:
Stage I: a single nodal or extranodal tumor manifestation without local spread (not: mediastinal and abdominal or epidural localizations - see stage III).
Stage II: multiple nodal and/or extranodal manifestations on the same side of the diaphragm with or without local spread(not: mediastinal, epidural or extensive non-resectable abdominal localizations - see stage III)
stage III: localizations on both sides of the diaphragm
- all manifestations in the thorax like mediastinum, thymus, pleura
- all extensive, non-operable (respectable) manifestations in the abdominal cavity (abdomen)
- affection of the outer meninges (epidural affection)
- multilocular bone involvement (not bone marrow involvement)
StageV: involvement of the bone marrow and/or the central nervous system (brain and spinal cord).
Note: Bone marrow involvement is defined as a blast percentage greater than 5% and less than 25% in the cytological examination of the bone marrow (bone marrow smear). If 25% or more blasts are present in the bone marrow, it is Burkitt's leukemia (L3-ALL). Any evidence of blasts in the cerebrospinal fluid (CSF) is considered an attack of the central nervous system. An infestation of the central nervous system is also given if any mass in the central nervous system with confirmed Burkitt's lymphoma in another location such as the chest, lower jaw and abdomen cannot be attributed to another cause.