Tetrasomy 8 in acute monoblastic leukemia (AML-M5a) with myelosarcomatosis of the skin.
We report a new case with isolated tetrasomy 8, an 82-year-old female patient in whom multiple disseminated nodular skin infiltrations up to 5 cm in diameter preceded acute monoblastic leukemia (AML-M5a). Despite an initial response to chemotherapy and radiotherapy, the patient died 1 year after diagnosis of relapsed leukemia. To assess the size of the tetrasomic clone, fluorescence in situ hybridization (FISH) analysis with a centromere-specific chromosome 8 probe was performed. Seventy percent of interphase cells showed four signals and 22% showed three signals. Because this trisomic clone was not detected by conventional cytogenetics, tetrasomic cells may have a proliferation advantage in vitro. Whether tetrasomy 8 arises from a simultaneous mitotic nondisjunction of both chromosomes 8 during one cell division or evolves secondarily from trisomy 8 through a second mitotic error is not known. Alternatively, trisomy 8 may originate from tetrasomy 8 by loss of one chromosome 8.
Marosi
C
C
Department of Internal Medicine I, University of Vienna, Austria.
Muhm
M
M
Argyriou-Tirita
A
A
Pehamberger
H
H
Pirc-Danoewinata
H
H
Geissler
K
K
Locker
G
G
Grois
N
N
Haas
O A
OA
D000368:Aged; D000369:Aged, 80 and over; D002869:Chromosome Aberrations; D002898:Chromosomes, Human, Pair 8; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D007948:Leukemia, Monocytic, Acute / Q000235:genetics* / Q000473:pathology; D007951:Leukemia, Myeloid / Q000235:genetics / Q000473:pathology; D017254:Leukemic Infiltration / Q000235:genetics* / Q000473:pathology; D012867:Skin / Q000473:pathology*