Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 19-2004. A 12-year-old boy with fatigue and eosinophilia

Cutaneous B-lymphoblastic lymphoma with IL3/IgH translocation presenting with hypereosinophilia and acute endocarditis

Hypereosinophilia is a rare phenomenon associated with childhood malignancy, predominantly acute lymphoblastic leukaemia. Causation is unclear and likely to have multiple mechanisms. We report a six year old boy presenting with hypereosinophilia and associated Loeffler endocarditis. Three months following his initial hypereosinophilia he developed cutaneous B-lymphoblastic lymphoma. Re-analysis of apparently uninvolved bone marrow, taken at initial presentation, revealed a single, previously unidentified, t(5;14)(q31;q32) positive cell. Using fluorescent in situ hybridisation, we demonstrate IL3/IgH@ fusion in cutaneous lymphoma cells. Our case confirms the association of hypereosinophilia and B-lymphoblastic lymphoma and strengthens the association between IL3 hypersecretion and hypereosinophilia.

Cardiac disease in a case of precursor B acute lymphoblastic leukaemia with eosinophilia(ALL/Eo)

Acute lymphoblastic leukaemia (ALL) is the most common paediatric malignancy. However, it may rarely associate with eosinophilia. Patients with ALL associated with eosinophilia (ALL/ Eo) have a grave prognosis and higher incidence of cardiac complications compared to standard lymphoblastic leukaemia. Reports of ALL/Eo disclosed a few case with cardiac involvement early in the course of leukaemia. Here, the authors report a case of 13-year-old boy who presented with peripheral eosinophilia, chest pain and a large left ventricular mass early in the course of precursor B- cell ALL associated with eosinophilia. He received multi-agent chemotherapy but succumbed to death 25 days after chemotherapy due to a refractory cardio respiratory failure.

Immunoglobulin heavy chain locus chromosomal translocations in B-cell precursor acute lymphoblastic leukemia: rare clinical curios or potent genetic drivers?

Chromosomal translocations involving the immunoglobulin heavy chain (IGH) locus define common subgroups of B-cell lymphoma but are rare in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Recent fluorescent in situ hybridization and molecular cloning studies have identified several novel IGH translocations involving genes that play important roles in normal hemopoiesis, including the cytokine receptor genes CRLF2 and EPOR, all members of the CCAAT enhancer-binding protein gene family, as well as genes not normally expressed in hemopoietic cells including inhibitor of DNA binding 4. IGH translocation results in deregulated target gene expression because of juxtaposition with IGH transcriptional enhancers. However, many genes targeted by IGH translocations are also more commonly deregulated in BCP-ALL as a consequence of other genetic or epigenetic mechanisms. For example, interstitial genomic deletions also result in deregulated CRLF2 expression, whereas EPOR expression is deregulated as a consequence of the ETV6-RUNX1 fusion. The possible clinical importance of many of the various IGH translocations in BCP-ALL remains to be determined from prospective studies, but CRLF2 expression is associated with a poor prognosis. Despite their rarity, IGH chromosomal translocations in BCP-ALL therefore define not only new mechanisms of B-cell transformation but also clinically important subgroups of disease and suggest new targeted therapeutic approaches.