No abstract

We analyzed tandem duplication in the juxtamembrane (JM) domain of the FLT3 (FMS-like tyrosine kinase 3/FLK2, CD135) gene in 94 children with acute myeloid leukemia (AML) and evaluated its correlation with clinical features. Longer polymerase chain reaction (PCR) products were observed in five patients; 1/3 of M0, 1/9 of M1, 1/39 of M2, 1/9 of M3 and 1/12 of M5. The sequence analyses of abnormal PCR products showed that all the abnormal products were derived from tandem duplications involving the JM domain and that all the lengthened sequences were in-frame as we previously reported. Statistical analyses revealed a significantly lower incidence of the tandem duplication in childhood AML patients than in adult patients (P Ͻ 0.05), and significantly shorter disease-free survival in patients with mutant FLT3 than in patients with wild-type FLT3 (P Ͻ 0.05). Our results suggest that the tandem duplication in the JM domain of the FLT3 gene is not a frequent phenomenon but might be a factor of poor prognosis in childhood patients with AML.

Summary Transient leukaemia (TL) in neonates with Down syndrome (DS) is characterized by the transient appearance of blast cells in the peripheral blood that resolves spontaneously. Some TL patients die at an early age due to organ failure. Seventy DS patients with TL were studied retrospectively to identify clinical and laboratory characteristics associated with early death (<6 months of age). Sixteen of 70 patients (22·9%) died early. The main causes of death were organ failure, particularly hepatic and cardiopulmonary failure. On univariate analysis, early gestational age (EGA), high white blood cell (WBC) count (≥100 × 109/l), percentage of peripheral blasts, elevated aspartate transaminase (AST), elevated direct bilirubin (DB), and low Apgar score were significantly associated with poor survival. On multivariate analysis, EGA, WBC count, and DB were independent predictors of poor outcome. A simple risk stratification system combining EGA and WBC count was devised to predict poor outcome. Term infants (EGA ≥ 37 weeks) whose WBC count was lower than 100 × 109/l had the best outcome [7·7% (3/39) died early], while preterm infants (EGA < 37 weeks) whose WBC count was higher than 100 × 109/l had the worst outcome [54·5% (6/11) died early]. This stratification system may be useful for identifying high‐risk patients who need early therapeutic interventions.

We performed continuous hyperthermic peritoneal perfusion (CHPP) or continuous normothermic peritoneal perfusion (CNPP) combined with cisplatin (CDDP) 300 mg/kg and mitomycin C (MMC) 30 mg/kg in an attempt to prevent peritoneal recurrence after surgery for gastric cancer. Twenty-two patients were treated with perfusion using about 10 liters of saline heated to 41 degrees to 42 degrees C (CNPP group); 18 patients were treated with saline heated to 37 degrees to 38 degrees C (CNPP group); and 18 patients underwent only gastric surgery without perfusion (control group) in a randomized control study. There were two deaths (9%) due to peritoneal recurrence in the CHPP group, four (22%) in the CNPP group, and four (22%) in the control group. The 1-, 2-, and 3-year survival rates were 95%, 89%, and 68%, in the CHPP group; 81%, 75%, and 51%, in the CNPP group; and 43%, 23%, and 23%, in the control group, respectively. There was a significant difference between the three survival curves by the log-rank test (p < 0.01). This difference showed that CNPP and CHPP are both effective procedures for preventing peritoneal recurrence. The maximum concentrations in the perfusate of total and free CDDP with 300 mg administration were 12.2 and 10.1 micrograms/ml, respectively, at the end of the perfusion, and the maximum concentrations of total and free CDDP in plasma were 2.1 and 1.0 micrograms/ml, respectively. The maximum concentrations of MMC in perfusate and plasma with 30 mg administration were 1.00 and 0.05 micrograms/ml, respectively, which are intraperitoneally cytotoxic but systemically safe concentrations.

We examined amplification of the c-met, c-erbB-2, and epidermal growth factor receptor (EGFR) gene in the patients with primary gastric cancer, and compared the data with clinical features in order to clarify the relationship between oncogenic abnormality and clinical features. Oncogene amplifications were examined by slot blot hybridization using DNAs extracted from formalin-fixed and paraffin-embedded tissues of primary gastric cancers. Seven of the seventy cancers (10.0%) had c-met gene amplification, nine (12.9%) had c-erbB-2 gene amplification, and six (8.6%) had EGFR gene amplification, respectively. Eighteen cases (25.7%) exhibited one or multiple oncogene amplification, and two cases (2.9%) exhibited simultaneous amplification of the three genes. The cases with c-met gene amplification tend to show invasive character and were related to peritoneal dissemination. The cases with c-erbB-2 gene amplification were related to lymph node metastasis. The cases with EGFR gene amplification had large tumors and were in highly advanced stage. The survival rate in patients with oncogene amplification was significantly lower than that in patients without amplification. Our data indicated that these genes were related to growth and metastasis of gastric cancer. Furthermore, this study about the three genes suggested that the type of activated gene might decide on the type of metastasis and clinical features.