Objective:
To explore the clinical features and
diagnosis methods of
atypical chronic myeloid leukemia (aCML).
Methods:
The clinical data,
bone marrow morphology,
immunology,
genetics and
molecular biology characteristics of a young aCML
patient in Nan'an Branch of the Second People's
Hospital of Yibin City in Sichuan Province were analyzed.
Results:
The
bone marrow smear showed that 0.875 of the
granulocyte system showed obvious proliferation, accompanied by significant dysplasia and immature granulocytosis; blasts accounted for 0.170, and the intracytoplasmic granules of mature
granulocytes were significantly increased and thickened.
Bone marrow puncture biopsy showed
bone marrow hyperplasia was extremely active, immature
granulocytes were increased, and
reticular fiber was extensively proliferated (
marrow fibrosis grade 2-3);
biopsy pathology results of left inguinal
lymph node showed
lymph node structure was destroyed,
megakaryocytes and immature
granulocytes could be seen in the background of
histiocytes, in line with the
marrow external
hematopoiesis;
bone marrow flow cytometry immunophenotype showed
granulocyte population accounted for 81.6% of nuclear
cells, abnormal expression of CD56 and CD14dim, abnormal
growth pattern of
granulocyte system; 30 common fusion
genes in
leukemia screening were negative.
Polymerase chain reaction (
PCR)
method showed BCR-ABL1 fusion
gene p210 type, BCR-ABL1 fusion
gene p190 type, BCR-ABL1 fusion
gene p230 type, CALR
gene exon 9, JAK2
gene V617F
mutation were all negative. Sanger sequencing showed MPL-W515
gene mutation, CSF3R
gene exons 14 and 17, BRAF
gene mutation, SRSF2 were all negative. Second-generation sequencing showed ASXL1
gene mutation was positive, NM_015338.5 c.2077C>T (p.R693*) and
mutation frequency was 47.7%; U2AF1
gene mutation was positive NM_006758.2 c.101C>A (p.S34V) and
mutation frequency was 51%; PDGFRA,
PDGFRB, SETBP1, SF3B1, STAT3, STAT5B were all negative.
Karyotype analysis showed 47, XX, add(5)(q33), +8, -10, +mar[8]. The integrated examination was diagnosed as aCML with negative BCR-ABL1.
Conclusions:
The
diagnosis of aCML with negative BCR-ABL1 depends on the comprehensive
diagnosis of morphology,
immunology,
genetics and
molecular biology. Second-generation sequencing is particularly important in the
differential diagnosis and targeted
drug therapy.
Early diagnosis and
treatment of young
patients is extremely challenging and should be paid more
attention for clinicians.