Photomicrograph of Burkitt's lymphoma.
HE-stained to the left and upper right. Ki67 staining lower right
The primary manifestation in most cases of Burkitt's lymphoma is an abdominal tumor in the iliocoecal region. Bone marrow involvement is relatively rare and is considered Burkitt's leukemia when more than 25% of nuclei-containing cells in marrow are tumor cells. A chromosomal translocation involving the c-MYC oncogene occurs in 100% of cases. Therefore, tumor should always be examined for one of the three c-MYC translocations by cytogenetics or FISH. Immunophenotypical data show that tumor is derived from germinal centers (CD10+, BCL6+). The cell profile is monomorphic with blastic nuclei.
The median age is about 30 years. Variants of Burkitt's lymphoma (plasmacytoid differentiation, Burkitt's-like) also have Myc translocations.
Burkitt's is the most rapid growing tumor with almost 100% Ki67-positive tumor cells. This means the disease progresses rapidly and treatment should be started immediately.
Treatment for this disease follows the same guidelines regardless of bone marrow involvement. Modern treatment given by university hospitals has improved the prognosis significantly. HDT with SCS, or similar regimens, given as consolidation treatment in the first remission does not appear to improve prognosis.
When treatment is started, tumor lysis syndrome occurs regularly and preventative measures must be taken. The treatment schedule in Norway has followed German guidelines (BFM variations) over the years with good results. The schedule is now changed. Rituximab is included and the GMALL-B-ALL/NHL 2002 protocol is followed. There is a specific schedule for patients over 55 years.