Comparison of clinical and biologic features between myeloid and lymphoid transformation of Philadelphia chromosome positive chronic myeloid leukemia.
Analysis of clinical and biologic features of chronic myeloid leukemia (CML) in blast crisis (BC) was performed on 36 patients: 25 had myeloid and 11 had lymphoid transformation. The median duration from diagnosis to onset of BC was significantly shorter in patients with lymphoid BC (6 months) than in those with myeloid BC (41 months). Patients in lymphoid transformation showed better response to therapy and had a significantly longer median survival time after BC than patients with myeloid transformation (56% vs 0% and 10 months vs 4 months, respectively). The leukemic cells from all the patients with lymphoid BC showed B-cell immunophenotype, confirmed by the presence of immunoglobulin (Ig) heavy chain gene rearrangements in the five patients studied. Two of the eight patients with complete marker study expressed myeloid-associated antigens on the blasts. A high incidence of CD7 expression (7/17 or 41%) was found in patients with myeloid BC, but none of the patients who had DNA analysis showed rearrangement of T-cell receptor beta chain gene. Chromosomal abnormalities +8, +19, +21, and i(17q) were detected only in the patients with myeloid BC but not in those with lymphoid BC. Combined analysis of the patients in this series and those reported previously has revealed a statistically significant difference in the distribution of bcr breakpoints between myeloid and lymphoid BC: the bcr breakpoints in more than half of the patients with myeloid crisis were mapped to Zone 2 while those in patients with lymphoid crisis occurred most frequently in Zone 3.
Ch'ang
H J
HJ
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Republic of China.
Tien
H F
HF
Wang
C H
CH
Chuang
S M
SM
Chen
Y C
YC
Shen
M C
MC
Lin
D T
DT
Lin
K H
KH
D000293:Adolescent; D000328:Adult; D000368:Aged; D001752:Blast Crisis / Q000235:genetics / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D015321:Gene Rearrangement; D006801:Humans; D016130:Immunophenotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000473:pathology*; D008875:Middle Aged; D015183:Restriction Mapping