ABSTRACT
Objective To investigate the clinical and laboratory features of acute promyelocytic leukemia (APL).Methotis 513 APL patients in the last two decades were retrospectively analyzed in this research.We investigated the clinical features including age,sex,abnormality of peripheral hemogram before treatment.therapeutic effect and follow-up and laboratory data such as morphology,immunology,cytogenetics and molecular biology(MICM).Results The median age of the APL patients was 33 years old and the ratio of male and female was 1.21:1.Before treatment,the median level of WBC was 4.3×109/L and the deteetion rate of abnormal promyelocyte on blood film was 85.8%;with immunophenotypie detection,the expression levels of CD117、CD34、HLA-DR、CD7、CD14 and CD19 in APL were found to be lower and the expression 1evels of CD2、CD33 and MPO higher than those in other subtypes of acute myelocytie leukemia(AML)(beth P<0.01).Specific abnormal chromosome t(15;17)was detected in 91.7%of the patients,of whom 75.9%had standard translocation of t(15;17),being the most common one and 15.8% of the patients had t(15;17)with additional abnormal chromosome.There was only 7.5%of the patients with nolnlal karyotype.However,the presence of both simple translocation and complex translocation was seldom seen.With molecular biological detection.PML/RARα fusion gene positive rate was 99.6%.In a relativelv long clinical follow-up,we found that the complete remission(CR)rate in APL patients was 84.7%.incidence of DIC was 13.4%and five-year survival rate was 30.7%.111e median count of WBC in CR group was lower than that non-remission group(P<0.01).There were no significant differences on expressions of CD34 and CD2 and changes of cytogenetics between the two groups(P>0.05).Conclusions Comprehensive evaluation of MICM could be of important significance in the diagnosis and prognosis iudgrnent for APL patients.The CR rate in these patients with high WBC eount was considerable low.
ABSTRACT
<p><b>OBJECTIVE</b>To present a special case with the karyotype and molecular marker of acute myeloid leukemia (AML)-M2 who was induced to complete remission by all-trans retinoic acid (ATRA) alone.</p><p><b>METHODS</b>A recently hospitalized young female patient with acute leukemia was initially diagnosed as M3 subtype based on morphological French-American-British (FAB) classification. Karyotype analysis using standard G and R banding techniques and RT-PCR were applied to further define the diagnosis. After primarily cultured bone marrow cells from the iliac aspiration were tested for in vitro induced differentiation, the patient was treated with oral all-trans retinoic acid alone, 60 mg per day until complete remission was achieved. Peripheral blood and bone marrow changes were monitored over the whole treatment course.</p><p><b>RESULTS</b>The characteristic chromosomal aberration for M3, the t(15;17) reciprocal translocation, was not found while a t(8;21) translocation was verified. Furthermore, an amplified product of the AML-1/ETO fusion gene instead of the PML/RAR alpha fusion gene was detected by RT-PCR and the diagnosis was corrected from M3 to M2. Primary cultured bone marrow cells can be fully induced to terminal differentiation after 4 days exposure to ATRA. A hematological complete remission was achieved after 40 days treatment with ATRA as a single therapeutic agent, suggesting an alternative pathway mediating ATRA-induced myeloid differentiation.</p><p><b>CONCLUSION</b>A leukemia patient with a subtype other than M3, such as M2 in this case, may also be induced to complete remission by the mechanism of ATRA-induced terminal differentiation. This implies that there may be a pathway other than PML/RAR alpha fusion gene product which mediates ATRA-induced myeloid maturation in leukemia cells.</p>