can be reached, several problems need to be solved. As to the concept of atypical leukemia, there are no true objective criteria. Historically it has undergone various changes, but there is as yet no established system of treatment for this disease. Five speakers will touch on these subjects. As regards non- Hodgkin's lymphoma, its classification is still in a flexible stage. Following Rappaport's classification, new classifications based on the Working Formulation have been proposed. In this country the LSG classification has almost taken root, and is used extensively because it is close to the Working Formulation. On the other hand, classification based on surface markers have also taken root. Two speakers will talk about the relationship between the classification of non-hodgkin's lymphoma and the therapeutic effects. Lastly, discussions will be held on the specific features of T-cell leukemia and lymphoma both of which are quite common in this country. Studies on the new approaches to classification of these diseases are ongoing, hand in hand, with the new advances in therapeutic methods for these diseases. CLINICAL FINDINGS AND CHROMOSOME ABNORMALITIES IN 120 ADULT CASES WITH ACUTE LEUKEMIA ACCORDING TO FAB CLASSIFICATION Keiko AIKAWA, Koki YOSHIDA and Chikara MIKUNI (Sapporo National Hospital, Hokkaido) The clinical findings and the chromosome abnormalities of acute leukemia according to FAB classification were evaluated. This study included 120 cases from Aug.1965 to May 1982 and these cases were 108 cases of acute myeloid leukemia and 12 cases of lymphoblastic leukemia. The classification of the 108 cases with acute myeloid leukemia was as follows. M1:25 cases, M2:53 cases, M3:17 cases, M4:7 cases, M5:6 cases and M6:none. The male/female ratio was 1.4. The mean age wsa as follows.39.4 years of age: M1, 42.6:M2, 34.1:M3, 45.6:M4, and 57.6;MS. There was a tendency to younger patients with M3 and older than 40 with most of M4, M5. Though there were no differences for RBC, hemoglobin among subgroups, in M 5, platelet was higher than others. The differences were not seen either for WBC, its leukemia cell ratio, and nucleated cell count in the bone marrow. Many cases in M 2, showed lower percentage of leukmia cell in the bone marrow. There was no differences for LDH and uric acid. Hepatomegaly was less common in both M3 and M5 than others, splenomegaly was not seen in M3, M4 and M5. Lymphadenopathy was seen in over 50% of both M4 and M5. Meningeal leukemia was seen in 36% of Ml. Gum hypertrophy was highly seen in
both M4 and M5, and skin infiltration was on M5. Chromosome abnormalities were observed in 43 out of 71 cases(60.6%) in which chromosome analysis was done. Abnormalities on each group were 13 out of 19 cases (68.4%) in M1, 18 out of 35 (51.4%) in M2, 11 out of 12 (91.7%) in M3, one out of 3 in M4 and none out of 2 in M5. The t (9;22) were found in 7 cases with M1 and one with M2, t (8;21) in 11 with M2, in which 4 cases were lack of sex chromosome, and t (1517) were in 11 cases with M3.50% survival time for each group were 9 months for M1, 6 months for M2, I month for M3, 6.3 months for M4, and 2 months for M5 respectively. Compaired to M1, when the complete remission (CR) was once established, M2 showed prolonged duration of CR. After the DCMP two step therapy was introduced in April 1977 the 50 o survival time were 12 months for M2 and 9 months for M1. Among 12 cases of acute lymphoblastic leukemia, 5 cases were L1, 7 were L2 and no L3 was observed. Most of the L1 cases had higher rate in leukemia cell of the bone marrow, hepatomegaly, splenomegaly and lymphadenopathy than L2. There was no significant differences between L1 and L2 as to the surface markers and survival time. FAB CLASSIFICATION AND RESPONSE TO CHEMOTHERAPY IN ADULT ACUTE NON-LYMPHOCYTIC LEUKEMIAS Hiromu OKADA and Toru MORIMOTO (Kyoto National Hospital, Kyoto) Response to chemotherapy in two groups of adult acute non-lymphocytic leukemias was analysed according to FAB classification. One group consisted of our 59 cases and another was national hospital co-operative group of 69 cases. The mean age of patients was higher in M4+5 type. Distributions of number in subtypes of FAB classification were about 30% in M1 and M2, 20% in M4+5, 10% in M3 and M6. Remission rates and mean survival periods of each group were 51.5% and 12.5 months in our group, and 62.9% and 10.8 months in co-operative group respectively. Remission rate was highest in M2, followed by M1 and M4+5, and lowest in M3. Days for remission were shortest in M4+5, and longest in M6. Mean survival period was significantly longer in M2 of our group, and shorter in M3 type. Several long-term survivers were found in M2. Above data suggest that the response to chemotherapy was better in M2. More effective chemotherapy for acute leukemias according to FAB classification should be established.
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