Details
Enlarging cheek mass.
Burkitt lymphoma is a fast-growing and aggressive B-cell lymphoma. Sections show a tumour comprised of intermediate sized lymphoid cells with scanty cytoplasm. The nuclei show coarse to focally vesicular chromatin and 1-2 basophilic nucleoli. Mitoses and karyorrhectic debris are abundant. Numerous tingible body macrophages are present creating a 'starry-sky' appearance. Entrapped fat is located within the neoplasm focally as well as the peripheral edge of one section. No normal lymph node tissue is noted. The atypical lymphoid cells express CD20, CD79a, CD10 (weak), and BCL-6. The MIB1 index is close to 100% in the neoplastic cells. Studies shows ~70% of cells are B lymphocytes positive for CD10, CD19 and CD20, CD22 and CD79a, showing lambda light chain restriction. The findings support a mature B cell lymphoma such as Burkitt lymphoma. Interphase FISH analysis with a dual colour breakapart probe for the MYC gene (8q24.1) showed a MYC gene rearrangement in ~75% of cells examined.