Clinical and genetic characteristics of Japanese Burkitt lymphomas with or without leukemic presentation.

To clarify the clinical and genetic features of Burkitt lymphoma with or without leukemic presentation, we have conducted clinical, cytogenetic, and genetic studies. Of 40 Japanese patients with Burkitt lymphoma examined by cytogenetic and/or fluorescence in situ hybridization analysis or Southern blot analysis using MYC probes, 35 patients had t(8;14) translocations, and 5 had t(8;22). Breakpoints were located far upstream of MYC in 4 (12%) of 33 tumors with t(8;14), and Epstein-Barr virus infection was found in 3 (8%) of 40 tumors. These findings are similar to those reported for non-Japanese patients with the sporadic form of Burkitt lymphoma. Clinical and genetic characteristic were compared for 30 patients presenting with lymphoma and 10 presenting with leukemia. The overall survival was shorter in aggressively treated leukemia patients than in aggressively treated lymphoma patients (P = .003); however, the incidence rates of TP53 mutation, p16INK4a deletion, and p15INK4b deletion that were found in 6 (15%) of 40,3 (9%) of 35, and 2 (6%) of 35 tumors, respectively, were similar between the 2 subtypes. Thus, the present study has shown the different prognoses for the 2 subtypes of Burkitt lymphoma but has failed to clarify the genetic backgrounds that may explain the different outcomes.

[Lineage switch on recurrence from minimally differentiated acute leukemia (M0) to acute megakaryocytic leukemia (M7)].

Phenotypic switch in acute leukemia is a rare phenomenon. We report on a female infant with minimally differentiated acute leukemia (M 0) which underwent a lineage switch on relapse. In March 1997, a 1-year-8-month old girl was admitted to our hospital with a high-grade fever and generalized purpura. Bone marrow showed 84% blasts. The blasts were negative for peroxidase, periodic acid-Schiff and alpha-naphthyl butyrate esterase. Immunophenotypic analyses of the blast cells were positive for CD 13, CD 33 antigens, as well as CD 34. Lymphoid markers all were negative. Though some blasts morphologically demonstrated cytoplasmic blebs, CD 41 was negative and ultrastructural platelet peroxidase was absent. Based on these hematological features, the patient was diagnosed as having AML-M 0. She was treated according to the Children's Cancer and Leukemia Study Group schedule and a complete remission was achieved 1.5 months after starting induction therapy. However, she relapsed in spite of continued chemotherapy in July 1997, when the cytomorphological pattern changed and the patient was diagnosed both morphologically and immunologically as having M 7. Electron microscopy revealed platelet peroxidase (+) and CD 41 (+). Cytogenetic studies on relapse demonstrated inv(3) (q 21 p 25). We attempted aggressive reinduction therapy, but without effect. The patient simultaneously developed severe pneumonia and died in February, 1998. A lineage switch on relapse and resistance to chemotherapy may be associated with the occurrence of genetic aberration.

[A study of allergological examination in infants and young children at first expiratory wheezing episode].

We investigated whether, in 117 infants and young children who experienced their first episode of wheezing, abnormal findings of allergological examination is present and can predict the development of asthma. The patients showed the significantly large number of peripheral eosinophils and the significantly high serum ECP and total IgE levels, as compared to those in controls. Specific IgE antibody was also positive at a high frequency in these patients. During the follow-up period of one year and 9 months on average, the incidence of wheezing episodes were significantly higher in the patients with high levels of ECP, total IgE and specific IgE in serum than in those with normal levels of these parameters. These results suggest that it is significant to conduct allergological examination even in infants and young children, who have had wheezing episode for the first time, for the purpose of providing against the subsequent occurrence of asthma.

[Clinical evaluation of urinary leukotriene e4 levels in children with respiratory syncytial virus infection].

The levels of leukotriene E4 (LTE4) of the urine were determined in 24 pediatric patients with infectious diseases due to respiratory syncytial virus (RSV), i.e., bronchitis, pneumonia, and bronchiolitis, and compared with those in controls without allergic disease. The level for LTE4 of the acute-phase urine was 620+/-562 pg/mg. cr in the pediatric patients infected with RSV, being significantly higher than 190+/-67 pg/mg. cr in controls (P<0.005). The levels for LTE4 of the urine in the recovery phase showed a tendency toward decrease, as compared to those in the acute phase. However, there was no significant difference in the level for LTE4 of the acute-phase urine between the presence and the absence of each of the following conditions: expiratory wheezing; the association of pneumonia; family history of allergic diseases; the association of atopic dermatitis; and a past history of expiratory wheezing. An allergological study also revealed that there was no significant difference in LTE4 level between the presence and the absence of peripheral eosinophilia or between the presence and the absence of the high total level for IgE of the serum or positivity for the specific IgE level in the serum. These results suggest that LT is involved with the pathological conditions of RSV infection, but there are no direct relation between atopic diathesis or expiratory wheezing and the amounts of LT production.