The role of trisomy 8 in the pathogenesis of chronic eosinophilic leukemia.
A case of chronic eosinophilic leukemia (CEL) manifesting as spinal cord compression by an extradural eosinophilic chloroma in a 32-year-old Chinese man was presented, who subsequently developed extramedullary transformation at the skin and then peritoneal cavity. Cytogenetic study of bone marrow cells at diagnosis showed a clonal karyotypic abnormality of trisomy 8 (+8), which on fluorescence in situ hybridization (FISH) was shown to be present in a clone of abnormal eosinophils, hence showing the neoplastic nature of the eosinophilic proliferation. There was another population of abnormal eosinophils that did not show +8. At blastic transformation, all blast cells in ascitic fluid were shown by FISH to harbor +8. These findings suggest that +8 in this case may have arisen from clonal evolution and is not the primary genetic event in leukemogenesis, but +8 most probably imparts a further survival advantage to the clone responsible for subsequent blastic transformation.
Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Hong Kong.
S K
SK
Ma
Y L
YL
Kwong
T W
TW
Shek
T S
TS
Wan
E Y
EY
Chow
J C
JC
Chan
L C
LC
Chan
D000328:Adult; D001201:Ascites / Q000235:genetics / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism; D002898:Chromosomes, Human, Pair 8; D002908:Chronic Disease; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000000981:diagnostic imaging / Q000235:genetics* / Q000378:metabolism; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D010532:Peritoneal Diseases / Q000378:metabolism / Q000473:pathology; D012871:Skin Diseases / Q000378:metabolism / Q000473:pathology; D014057:Tomography, X-Ray Computed; D014314:Trisomy
D014408:Biomarkers, Tumor