Histology Course A IV 24 Department of Pathology, University of Zurich Histokurs

A IV 24 burkitt lymphoma (WHO 2001) HE further information (German) on HiPaKu 
  ICD-10: C83.7; ICD-O: 9687/3
 
   
46-year-old male underwent excision of an enlarged, indolent lymph node at the jaw.
 
- The lymph node architecture is destroyed by a monotonous population of loosely arranged intermediate-sized cells (between small lymphocytes and immunoblasts) in a capillary network.
- The cells display round to oval somewhat irregular nuclei with a fine to coarse chromatin and 2-5 prominent nucleoli.
- A moderate amount of weakly basophilic to amphophilic cytoplasm is observed.
- The high mitotic rate is characteristic of this tumor.
- Death of single or groups of cells leads to the concomitant presence of tissue macrophages containing cellular debris. At lower magnification, the so-called “starry sky” pattern can be appreciated which is created by the lightly stained macrophages surrounded by clear spaces.


Etiology:
Three distinct clinical forms of Burkitt lymphoma are distinguished.
1) Endemic Burkitt lymphoma: Burkitt lymphoma is endemic especially in malarious parts of Africa. Typically, tumor cells in virtually all patients harbor the EBV genome.
2) Sporadic Burkitt lymphoma: In the US, Burkitt lymphoma accounts for less than 1% of non-Hodgkin lymphomas in adults, but for about 30% of non-Hodgkin lymphomas in children.
3) Immunodeficiency-associated Burkitt lymphoma: Burkitt Lymphoma accounts for about 20% of all lymphomas in patients with AIDS. It is rarely seen in the setting of other immunodeficiencies. Only 50% of HIV-associated Burkitt lymphomas are positive for EBV.

Localization:
Extranodal sites are frequently affected (ovaries, bone marrow, GI-tract).

Cytogenetic abnormality:
Translocation of the MYC locus on chromosome 8 to the IgH gene on chromosome 14.

Burkitt lymphoma is a high-grade lymphoma.