Résumé
BACKGROUND: Because specific chromosomal abnormalities are associated with certain hematologic disorders, cytogenetic studies can help classifing the diseases, providing the clues of disease progression and being used to monitor remission after chemotherapy. In this study, cytogenetic analysis was performed. In acute and chronic leukemic patients in Korea and the results were compared with foreign cytogenetic reports, and the typical acute lymphocytic leukemia (ALL) and acute myelocytic leukemia (AML) associated chromosome aberrations were analysed by some calculated parameters to clarify if the specific chromosomal abberations in the specific types or subtypes of leukemias had diagnostic value or not. METHOD: Chromosome studies were done in bone marrow or peripheral blood samples by high resolution banding technique. Sensitivity, specificity, and positive and negative predictive values of finding or not finding a given aberration were calculated for followings : for the differential diagnosis between ALL and AML when a patient is known to have acute leukemia, for the differential diagnosis among AML and ALL FAB subtypes in a patient with known AML and ALL. RESULTS: The high positive predictive values (1.0) in the AML versus ALL comparison were found for -7, del(7) (q11-34q22-36), +8s, t(8;21) (q22;q22), t(15;17) (q22;q11), inv (16) (q13;q22) and -Y. Among the AML subtypes, the highest sensitivity, positive and negative predictive values were 0.85, 0.97, 0.94 for t(15;17) (q22;q11) in M3, respectively. The high positive predictive values and specificity in the ALL versus AML comparison were found for t(1;19) (q23;p13) ,t(4;11) (q21 ;23) and t(8; 14) (q24;q32) Among the ALL subtypes, the highest negative predictive value was 0.99 for t (8;14) (q24;q32) in L3. Among 398 CML cases, Philadelphia chromosome positive CML were shown in 81.9% that were classic t(9;22) (q34;all) (94.5%), complex variant traslocation(1.8%) and additional secondary chromosome aberrations (3.7%) . CONCLUSION: Total chromosomal aberration rate in acute and chronic leukemia in Korea was lower than that in foreign reports, but the patterns of chromosome aberrations were similar except for t(15;17) (q22;q11) in AML patients. Quantitativly calculated data of sensitivity, specificity and positive and negative predictive values in the specific chromosomal aberration might be used for diagnostic markers of acute leukemia.