A pregnant woman with thymoma-associated pure red cell aplasia

Background

Pure red cell aplasia (PRCA) is a hematological disorder characterized by anemia with severe reticulocytopenia caused by a marked reduction in erythroid precursors in the bone marrow. PRCA is known to be associated with pregnancy, but thymoma-associated PRCA during pregnancy is very rare, and its successful management has not been reported.

Case presentation

A 37-year-old primiparous woman with severe anemia was referred to our center at 27 weeks’ gestation. She was diagnosed with PRCA based on bone aspiration findings at 33 weeks’ gestation. Magnetic resonance imaging (MRI) revealed an anterior mediastinal mass 4 cm in size suspected of being thymoma. She was therefore diagnosed with thymoma-associated PRCA during pregnancy. Surgery for thymoma was planned after delivery, since the imaging findings were suggestive of early-stage thymoma (Masaoka stage I or II). With transfusion of a total 3,360 ml of red blood cells (RBCs) during pregnancy, the patient gave birth to a baby girl weighing 2,548 g at 40 weeks’ gestation. The baby showed transient congenital cutaneous candidiasis. The placental pathology revealed subamniotic inflammation with a fungal structure. Treatment with topical anti-fungal cream immediately ameliorated the baby’s skin lesion. Maternal anemia did not improve after delivery; however, the thymoma did not increase in size. At five months after delivery, the mother underwent thymectomy with oral cyclosporine A. A pathological examination revealed Masaoka stage II-a thymoma. She completely had recovered from anemia at six months after surgery. Cyclosporine A treatment was discontinued three years after surgery. Remission has been sustained for four years since surgery.

Conclusions

A very rare case of thymoma-associated PRCA during pregnancy was diagnosed without any subjective symptoms and was expectantly managed, resulting in a good prognosis. Although bone marrow aspiration during pregnancy is an invasive test, it is important to confirm the diagnosis. Conservative management with blood transfusion was possible for early-stage thymoma-associated PRCA during pregnancy. Active surveys, including MRI, for PRCA during pregnancy led to the detection of thymoma at an early stage and the achievement of a preferable pregnancy outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05145-5.

Clinical conditions and risk factors for inhibitor-development in patients with haemophilia: A decade-long prospective cohort study in Japan, J-HIS2 (Japan Hemophilia Inhibitor Study 2)

BACKGROUND

Inhibitor-development is a serious complication in patients with haemophilia (PwH). Previous studies reported that therapeutic and genetic factors could be associated with these alloantibodies. Relevant clinical features such as genetic-background and different treatment regimens in Japan remain unclear, however.

AIMS

To analyse a nation-wide Japanese registry for PwH, and to examine risk factors for inhibitor-development.

METHODS AND RESULTS

Newly diagnosed patients with haemophilia A (PwHA) or haemophilia B (PwHB) without inhibitors after 2007, and with treatment records traceable from 0 to 75 exposure days (ED), were enrolled in the Japan Hemophilia Inhibitor Study 2 (J-HIS2) initiated in 2008. Of 417 patients (340 PwHA, 77 PwHB) from 46 facilities, 83 (76 PwHA, 7 PwHB) were recorded with inhibitors by July 2020. Inhibitors were observed in 31.0% of severe PwHA, 8.0% moderate and 1.6% mild and in 17.1% of severe PwHB. The majority of inhibitors (89.7% in severe PwHA and 71.4% in severe PwHB) were detected on or before 25ED (median 12ED in PwHA and 19ED in PwHB). Genotyping in these severe patients identified an association between inhibitor-development and null variants of F8 (P < .01) or F9 (P < .05). A lower incidence of inhibitors was recorded in severe PwHA treated with prophylaxis than in those treated on-demand (P < .01). A past-history of intracranial-haemorrhage appeared to be associated with inhibitor-development, while FVIII-concentrates infusion and routine vaccination on the same day was not related to inhibitor-development.

CONCLUSION

The J-HIS2 study has identified significant clinical variables associated with inhibitor-development in Japanese PwH, consistent with other global studies.

Frequent breakpoints of focal deletion and uniparental disomy in 22q11.1 or 11.2 segmental duplication region reveal distinct tumorigenesis in rhabdoid tumor of the kidney

SMARCB1 is mutated in most rhabdoid tumors (RTs) developing in the kidney (RTK) and various other organs. Focal deletions found in patients with 22q11.2 deletion syndrome show breakpoints within clusters of segmental duplications (SDs), and those in some RTs show breakpoints in the 22q11-q12 region. SDs are known to cause focal deletion mediated by non-allelic homologous recombination. The present study identified SMARCB1 alterations in all 30 RTKs, using SNP array CGH, MLPA, and sequence analyses. Twenty-eight tumors had a total of 51 breakpoints forming focal 22q deletion and/or uniparental disomy (22qUPD), and the other two had compound mutation with no breakpoints in 22q. Twenty-four (47.1%) of the 51 breakpoints were within SDs, and occurred in 16 (53.3%) of the 30 tumors. The association of breakpoints with SDs was found not only in focal deletion, but also in 22qUPD, indicating that SDs mediate the first and second hits (focal deletion) and the second hit (22qUPD) of SMARCB1 alteration. Of the 51 breakpoints, 14 were recurrent, and 10 of the 14 were within SDs, suggesting the presence of hotspots in the 22q11.2 region. One recurrent breakpoint outside SDs resided in SMARCB1, suggesting inactivation of the gene by out-of-frame fusion. The association between SDs and focal deletion has been reported in two other types of cancer. RTKs may be the third example of SD-associated tumors. Thus, the present study indicated that RTKs exploit genomic instability in the 22q11.1-11.2 SDs region, and 22qUPD caused by mitotic recombination may also be mediated by SDs.

Lupus anticoagulant hypoprothrombinemia syndrome associated with bilateral adrenal haemorrhage in a child: early diagnosis and intervention

BACKGROUND

Lupus anticoagulant-hypoprothrombinemia syndrome (LAHPS) is characterized by bleeding and thrombosis in patients with autoimmune diseases or infections. Paediatric LAHPS exhibits various degrees of bleeding, ranging from mild to severe; however, adrenal haemorrhage due to LAHPS and its long-term clinical course have not been sufficiently described.

CASE PRESENTATION

A 9-year-old boy presented with prolonged abdominal pain and abnormal coagulation screening tests. The laboratory tests showed prolonged activated partial thromboplastin time and subsequently revealed the presence of lupus anticoagulant, anti-nuclear antibodies, and hypoprothrombinemia, leading to diagnosis of LAHPS. An enhanced computed tomogram demonstrated nodular lesions in the adrenal glands bilaterally, suggestive of adrenal haemorrhage. Laboratory and clinical manifestations exhibited life-threatening adrenal insufficiency that required hydrocortisone administration. The patient developed systemic lupus erythematosus, diagnosed 12 months later.

CONCLUSIONS

This patient with LAHPS developed rare adrenal failure due to adrenal haemorrhage, a life-threatening event that should be recognized and treated early. In our case, renal dysfunction was also observed when systemic lupus erythematosus was diagnosed 1 year after LAHPS. Our case emphasizes that early recognition of adrenal failure and careful long-term observation is required in patients with autoantibodies.

[Dislodgement of a long-term inserted catheter from the connecting parts of an implantable central venous port in a child with hemophilia]

A central venous access device (CVAD) was implanted in a child with hemophilia for long-term replacement therapy with factor VIII. Four years and eight months after its insertion, malfunction was observed. Further study revealed migration of the transected catheter to both the pulmonary arteries. The retrieved catheter displayed a tear and dislodgement at the anastomosis between the port and catheter. To the best of our knowledge, no case of extensive CVAD damage in children with hemophilia has been reported. Patients with CVAD malfunction are often asymptomatic; however, this condition could lead to a fatal outcome. Therefore, clinicians need to be aware of this complication.

Clinical Prognostic Factors in Pediatric Patients With Orthostatic Intolerance

Midodrine is widely used for orthostatic intolerance (OI); however, little is known about the prognostic factors of OI after midodrine treatment. We retrospectively reviewed electronic medical charts to investigate clinical prognostic factors of OI on 159 OI patients aged 7 to 18 years who were treated with midodrine at a children's hospital. Logistic regression was conducted to clarify predictors for improving symptoms at the first month of the treatment. Patients with orthostatic uncomfortable feeling or fainting were significantly more likely to improve symptoms at the first month of the treatment (odds ratio [OR], 3.48; 95% confidence interval [95%CI], 1.36-8.89), but patients with underweight were significantly less likely to improve symptoms (OR, 0.19; 95%CI, 0.06-0.56). Our results suggest that predictive factors for OI by midodrine treatments are orthostatic symptoms and underweight in pediatric patients. These findings are useful to develop further studies for OI treatments.

[Successful treatment by switching from activated prothrombin complex concentrate to emicizumab therapy in a hemophilia A patient with inhibitors]

A 7-month-old male infant with severe hemophilia A who received on-demand therapy with recombinant factor VIII (rFVIII) vomited because of acute intracranial bleeding. With rFVIII treatment for suppressing bleeding, there was development of high-titer (≤673 BU/ml) inhibitors. The patient was administered bypassing agents followed by immune tolerance induction therapy (ITI) with 50 U/kg of FVIII thrice weekly. In addition, he was treated with weekly and thrice weekly prophylaxis with 50 U/kg of activated prothrombin complex concentrate (aPCC). Despite ITI and aPCC prophylaxis treatments, it was difficult to control the hemorrhage, and the annualized bleeding ratio (ABR) remained high (5-13 bleeding episodes per year). We started emicizumab 2 weeks after completing the administration of aPCC. Weekly subdermal injections of 1.5 mg/kg emicizumab after loading dramatically decreased ABR (one bleeding episode per year), although biweekly injections of 3 mg/kg emicizumab for several months were associated with one joint hemorrhage. Compared to regular aPCC administration, our observations suggest that weekly emicizumab treatments can improve the ABR in a hemophilia patient with inhibitors and improve the quality of life of patient without limitations in terms of school events.

A Japanese Family with the Unstable Hb Sydney (HBB: c.203T>C) Variant and Persistent Low Hemoglobin Oxygen Saturation

Patients with unstable hemoglobin (Hb), caused by a qualitative abnormality in α- and β-globin genes, are often asymptomatic or mildly symptomatic. It is often difficult to diagnose unstable Hb patients with only mild hemolysis or low oxygen saturation. We herein report a case of a family with an unstable Hb, specifically, Hb Sydney (HBB: c.203T>C), an abnormal β-globin chain. A 5-year-old boy was referred to our hospital for low percutaneous oxygen saturation (SpO₂) in the setting of bronchitis. During hospitalization, low SpO₂ persisted despite the improvement in respiratory distress symptoms. As he had mild hemolysis and splenomegaly, his disease was diagnosed to carry Hb Sydney based on gene analysis. His mother and brother also carried Hb Sydney. In this case, bronchial asthma had been treated, but unstable Hb was not assessed. Low SpO₂ may be tolerated and overlooked in cases of asthma and it took time to diagnose this patient. The present case suggests that unstable Hb should be considered in patients with bronchial asthma and prolonged low SpO₂.

Slow Elevation in Protein C Activity without a PROC Mutation in a Neonate with Intracranial Hemorrhage

Severe protein C (PC) deficiency leads to purpura fulminans and stroke in newborns. However, the clinical impact of plasma PC activity on the development of neonatal cerebral disease remains elusive. We report a case of hemorrhagic stroke associated with neonatal asphyxia and severe PC deficiency. Plasma PC and protein S activity 7 days after birth was 12% and 43%, respectively. No PROC mutation was found. PC levels did not exceed 20% until 2 months of age, even in the absence of consumption coagulopathy or vitamin K deficiency. Neither thromboembolic nor hemorrhagic events occurred during the infusion of activated PC concentrate (twice weekly, up to 68 days after birth). The PC activity levels gradually increased to the standard value for age by 9 months of age. The present case showed that neonatal PC deficiency without a PROC mutation caused an intracranial hemorrhage before a slow increase in PC activity.

Acquired idiopathic thrombotic thrombocytopenic purpura successfully treated with intravenous immunoglobulin and glucocorticoid: A case report

RATIONALE

Plasma exchange is the principal treatment for acquired thrombotic thrombocytopenic purpura (TTP) but is invasive and may have adverse effects. Reports of immunoglobulin therapy for acquired TTP without plasma exchange are rare.

PATIENT CONCERNS

A 14-year-old girl was admitted because of hemolytic anemia and thrombocytopenia.

DIAGNOSIS

Acquired TTP was diagnosed based on low ADAMTS13 (a disintegrin-like and metalloproteinase with thrombospondin type 1 motif, 13) activity and a high ADAMTS13 inhibitor level.

INTERVENTIONS & OUTCOMES

Fresh frozen plasma was initially effective. Prednisolone and immunoglobulin resolved the condition with no adverse effects and rendered plasma exchange unnecessary.

LESSONS

Compared with biological agents, immunoglobulin is cost-effective, readily available, and has a proven long-term safety record, making it a possible treatment option for acquired thrombotic thrombocytopenic purpura.

Pediatric Thromboembolism in Japan

OBJECTIVES

To investigate the clinical and epidemiologic characteristics of thromboembolism in Japanese children.

METHODS

Clinical data of 77 patients with thromboembolism from a national tertiary pediatric care center were reviewed.

RESULTS

Incidence of thromboembolism was calculated to be 15 per 10,000 hospital admissions. Infants younger than one year of age made up the largest age group (25 patients, including nine neonates younger than 30 d). The occurrence of thromboembolism increased over the years in the index population. Thromboembolism was diagnosed as follows: portal vein thrombosis (n = 15), obstruction of central venous catheter (n = 13) and cerebral infarction (n = 9). Among the 77 patients, there were eight mortalities and six significant sequelae.

CONCLUSIONS

In pediatric care, especially in intensive care, we should pay more attention to thromboembolism in order to detect it promptly.

Successful living domino liver transplantation in a child with protein C deficiency

PC is produced in the liver and inhibits blood coagulation by catalyzing active factors V and VIII. PC deficiency causes abnormal blood clotting that is difficult to regulate by anticoagulative treatments. Four reports of PC deficiency treated with LTx have been published; however, no report of DLT as a therapy for PC deficiency is available. We describe a case of a 23-month-old girl who received DLT for compound heterozygous PC deficiency. Her PC activity was below 5%. She developed intracranial lesion and frequent refractory purpura fulminans. Both her parents had heterozygous mutations of PC genes and were excluded as living donors. Furthermore, she was a low priority on the waiting list of deceased-donor transplantation. We performed living DLT using the liver from a patient with MSUD. Activated PC concentrate safely supported the perioperative period. After DLT, she maintained normal PC activities and BCAA levels. This is the first case of PC deficiency successfully treated by living DLT with MSUD. We propose that DLT using liver from patients with MSUD is a treatment option for PC deficiency.

Pain management during bone marrow aspiration and biopsy in pediatric cancer patients

BACKGROUND

The pain associated with bone marrow aspiration and biopsy (BMAB) has an enormous impact on pediatric cancer patients and their families, but no specific reference standards for sedation and analgesia have been developed in Japan. To determine the problems associated with pain management during BMAB, a cross-sectional investigation was conducted.

METHODS

A survey was sent in October 2011 to data managers in institutions belonging to the Tokyo Children's Cancer Study Group, addressing the non-pharmacological and pharmacological pain management for BMAB performed on pediatric cancer inpatients between January 2010 and December 2010.

RESULTS

The eligible response rate was 41 of 57 institutions (71.9%). Non-pharmacological pain intervention was provided in 68% of surveyed institutions. All institutions provided pharmacological pain management. In most institutions, sedation/analgesia was performed by pediatric oncologists in a treatment room in the ward. Standards for pain management were developed and utilized in only four institutions. Other means of pain management were provided in various settings. Twelve institutions reported insufficient sedation/analgesia. In total, 80% of institutions reported some adverse events. Two serious adverse events were reported in cases of underlying or complicated conditions. No serious long-term consequences were reported.

CONCLUSIONS

Significant issues were identified regarding the efficacy and safety of pain management. Adverse events can occur in any institution. Children with underlying or complicated conditions are at high risk for serious adverse events. Therefore, adequate and systematic assessment, patient monitoring, preparation and treatment for adverse events, and cooperation with skilled specialists of pediatric oncology, anesthesiology, and intensive care are essential.

Long-term follow-up of children with refractory immune thrombocytopenia treated with rituximab

Data on long-term outcomes of children with refractory immune thrombocytopenia (ITP) treated with rituximab are limited. We retrospectively analyzed the long-term effect of rituximab on 22 pediatric ITP patients (11 boys and 11 girls). Compete response (CR) (platelet count ≥100 × 10(9)/L) and partial response (PR) (platelet count 30-99 × 10(9)/L) were achieved in nine (41 %) and two (9 %) patients, respectively. Of the 11 responders, eight subsequently relapsed 2-26 months after initial rituximab treatment. The 5-year relapse-free rate was 14 % (3/22, 95 % confidence interval: 0-27 %) with a median follow-up period of 6.4 years. Five initial responders with subsequent relapse and one non-responder received multiple rituximab treatments of nine courses; all patients responded to the second rituximab therapy without any significant toxicity. All eight patients who relapsed after an initial response and six of 11 non-responders achieved CR or PR with subsequent treatment, including repeated courses of rituximab, splenectomy, steroids, and other immunomodulating agents. Our findings indicated that the sustained effect of rituximab on children with refractory ITP is low, but that the long-term outcome of ITP itself is not poor. Furthermore, repeated rituximab administration may be a promising therapy for those who relapse after an initial response.

Methylenetetrahydrofolate reductase gene haplotypes affect toxicity during maintenance therapy for childhood acute lymphoblastic leukemia in Japanese patients

Abstract The aim of this study was to investigate the influence of daily 6-mercaptopurine (6-MP) and low-dose weekly methotrexate (MTX) combination treatment and methylenetetrahydrofolate reductase (MTHFR) haplotypes on toxicity during maintenance therapy in Japanese childhood acute lymphoblastic leukemia (ALL). We retrospectively analyzed the MTHFR C677T and A1298C polymorphisms and influence of haplotypes on toxicity in 73 patients. Patients with the MTHFR 677TT and 677CT + 1298AC were associated with severe liver toxicity (p = 0.014, odds ratio [OR] = 3.82, 95% confidence interval [CI] = 1.27-11.46) and more rapid onset of liver toxicity (p = 0.010). Patients with MTHFR 677TT and 677CT + 1298AC were associated with lower frequency of 6-MP and MTX dose reduction due to leukopenia (p < 0.05). No difference was observed in average drug doses in the MTHFR genotypes. In conclusion, the MTHFR C677T and A1298C haplotypes might be useful for monitoring adverse effects in childhood ALL maintenance therapy in Japanese patients.

Wiskott-Aldrich syndrome presenting with a clinical picture mimicking juvenile myelomonocytic leukaemia

BACKGROUND

Wiskott-Aldrich syndrome (WAS) is a rare X-linked immunodeficiency caused by defects of the WAS protein (WASP) gene. Patients with WAS typically demonstrate micro-thrombocytopenia.

PROCEDURES

The report describes seven male infants with WAS that initially presented with leukocytosis, monocytosis, and myeloid and erythroid precursors in the peripheral blood (PB) and dysplasia in the bone marrow (BM), which was initially indistinguishable from juvenile myelomonocytic leukaemia (JMML).

RESULTS

The median age of affected patients was 1 month (range, 1-4 months). Splenomegaly was absent in four of these patients, which was unusual for JMML. A mutation analysis of genes in the RAS-signalling pathway did not support a diagnosis of JMML. Non-haematological features, such as eczema (n = 7) and bloody stools (n = 6), ultimately led to the diagnosis of WAS at a median age of 4 months (range, 3-8 months), which was confirmed by absent (n = 6) or reduced (n = 1) WASP expression in lymphocytes by flow cytometry (FCM) and a WASP gene mutation. Interestingly, mean platelet volume (MPV) was normal in three of five patients and six of seven patients demonstrated occasional giant platelets, which was not compatible with WAS.

CONCLUSIONS

These data suggest that WAS should be considered in male infants presenting with JMML-like features if no molecular markers of JMML can be detected.

[Successful management of neurosurgical procedures with continuous infusion of recombinant factor IX in a child with hemophilia B]

This report describes the successful management of neurosurgical procedures with continuous infusion of recombinant factor IX (rFIX). A 1-year-old boy with severe hemophilia B was administered prophylactic therapy with rFIX after intracranial bleeding. We found the enlargement of an arachnoid cyst in a follow-up CT scan. He underwent marsupialization of the cyst under the continuous infusion of rFIX. FIX levels were examined in our hospital and the rFIX infusion rate was adjusted in an attempt to keep FIX levels above 90% intraoperatively, and 70% until his 7th post-operative day. We studied the pharmacokinetic profile of rFIX and found a half-time of 25 hours and mean in vivo recovery of 0.69 IU/dl/IU/kg. Reconstituted rFIX also retained at least 95% activity after 72 hours at room temperature. This is the first report of the perioperative management of a child undergoing a neurosurgical procedure under the continuous infusion of rFIX in Japan. Further studies are required before the routine use of this product for continuous infusion.

Methylation of the RASSF1A promoter is predictive of poor outcome among patients with Wilms tumor

BACKGROUND

Wilms tumor (WT) has a survival rate of 90% following multimodality therapy. Nevertheless, there are some groups of patients with event-free survival rates less than 75%. In addition to clinical prognostic factors, loss of heterozygosity at 1p and/or 16q has been used to determine treatment intensity. However, the incidence of this abnormality is low, and new biomarkers are still needed.

PROCEDURE

We analyzed methylation status of three tumor suppressor genes; Ras-association domain family 1 protein, isoform A (RASSF1A), DCR2, and CASP8, in 84 WTs using conventional methylation-specific PCR (cMSP), and the results were correlated with outcome. Furthermore, we analyzed the methylation status of RASSF1A by quantitative MSP (qMSP) in 171 WTs, and evaluated clinical and genetic differences between the methylated and unmethylated tumors.

RESULTS

RASSF1A was the most frequently methylated gene identified by cMSP, and associated with a poor outcome. Patients with a RASSF1A-methylated tumor had shorter overall and event-free survival periods (P = 0.043 and 0.018, respectively), when a cut-off value of 7% by qMSP was used. The methylation was more frequent in tumors of older children than younger children (P < 0.001), and in advanced-stage tumors than early stage tumors (P = 0.001). However, multivariate analysis could not confirm the prognostic significance of RASSF1A methylation, possibly because of a small number of advanced stage tumors examined. RASSF1A methylation was correlated with LOH at 1p and/or 16q (P = 0.017), but not with WT1 abnormality, suggesting the methylation and LOH to involve the same tumorigenic pathway.

CONCLUSIONS

The methylation status of RASSF1A might be a novel biomarker to predict outcome of WT patients.

Different incidences of epigenetic but not genetic abnormalities between Wilms tumors in Japanese and Caucasian children

Epidemiological studies show that the incidence of Wilms tumor (WT) in East-Asian children is half of that in Caucasian children. Abnormalities of WT1, CTNNB1, WTX, and IGF2 were reported to be involved in Wilms tumorigenesis in Caucasians, although none of the studies simultaneously evaluated the four genes. WTX forms the β-catenin degradation complex; however, the relationship between WTX abnormality and CTNNB1 mutation was uncertain in WTs. We examined abnormalities of the four genes in 114 Japanese with WTs to clarify the relationship between genetic and epigenetic factors and the incidence of WTs. We found that abnormalities of WTX and CTNNB1 were mutually exclusive, and that although CTNNB1 mutation was frequent in WTs with WT1 abnormality, but rare in WTs without, the incidences of WTX abnormality were similar between WTs with or without WT1 abnormality. These findings were consistent with those reported in Caucasian populations, and indicate multiple roles of WTX abnormality. Abnormalities of WT1, WTX and CTNNB1, and loss of IGF2 imprinting (LOI) were detected in 31.6%, 22.8%, 26.3%, and 21.1% of the 114 WTs, respectively. When we selected 101 sporadic WTs, the incidences of WT1, CTNNB1, or WTX abnormality were generally comparable between the two populations, whereas the incidence of IGF2 LOI was lower in Japanese than that of IGF2 LOI reported in Caucasians (P = 0.04). This is the first comprehensive study of the four genes, and the results supported the hypothesis that the lower incidence of IGF2 LOI contributes to the lower incidence of WTs in Japanese children.

The activity of the inosine triphosphate pyrophosphatase affects toxicity of 6-mercaptopurine during maintenance therapy for acute lymphoblastic leukemia in Japanese children

The association between inosine triphosphate pyrophosphatase (ITPA) activity and toxicity of 6-mercaptopurine (6-MP) was retrospectively evaluated in 65 Japanese children with acute lymphoblastic leukemia (ALL). Patients with an ITPA activity of less than 126 μmol/h/gHb presented with hepatotoxicity more frequently than those with higher ITPA activity (p<0.01). The average 6-MP dose during maintenance therapy administered to two patients with the ITPA deficiency was lower than that given to the other patients. Measuring ITPA activity is important for ensuring the safety of maintenance therapy for Asians with ALL because thiopurine S-methyl transferase mutations are rare in the Asian population.

Validation of the Japanese version of the Pediatric Quality of Life Inventory (PedsQL) Cancer Module

Background

The PedsQL 3.0 Cancer Module is a widely used instrument to measure pediatric cancer specific health-related quality of life (HRQOL) for children aged 2 to 18 years. We developed the Japanese version of the PedsQL Cancer Module and investigated its reliability and validity among Japanese children and their parents.

Methods

Participants were 212 children with cancer and 253 of their parents. Reliability was determined by internal consistency using Cronbach's coefficient alpha and test-retest reliability using intra-class correlation coefficient (ICC). Validity was assessed through factor validity, convergent and discriminant validity, concurrent validity, and clinical validity. Factor validity was examined by exploratory factor analysis. Convergent and discriminant validity were examined by multitrait scaling analysis. Concurrent validity was assessed using Spearman's correlation coefficients between the Cancer Module and Generic Core Scales, and the comparison of the scores of child self-reports with those of other self-rating depression scales for children. Clinical validity was assessed by comparing the on- and off- treatment scores using Kruskal-Wallis and Mann-Whitney U tests.

Results

Cronbach's coefficient alpha was over 0.70 for the total scale and over 0.60 for each subscale by age except for the 'pain and hurt' subscale for children aged 5 to 7 years. For test-retest reliability, the ICC exceeded 0.70 for the total scale for each age. Exploratory factor analysis demonstrated sufficient factorial validity. Multitrait scaling analysis showed high success rates. Strong correlations were found between the reports by children and their parents, and the scores of the Cancer Module and the Generic Core Scales except for 'treatment anxiety' subscales for child reports. The Depression Self-Rating Scale for Children (DSRS-C) scores were significantly correlated with emotional domains and the total score of the cancer module. Children who had been off treatment over 12 months demonstrated significantly higher scores than those on treatment.

Conclusions

The results demonstrate the reliability and validity of the Japanese version of the PedsQL Cancer Module among Japanese children.

Nationwide survey of bisphosphonate therapy for children with reactivated Langerhans cell histiocytosis in Japan

BACKGROUND

Several studies have suggested that Langerhans cell histiocytosis (LCH) is responsive to treatment with bisphosphonates (BPs). However the efficacy and safety of BPs therapy for childhood LCH is unknown.

PROCEDURE

Data on children with LCH who had received BPs therapy were collected retrospectively from hospitals participating in the Japanese Pediatric Leukemia/Lymphoma Study Group.

RESULTS

Twenty-one children with histologically proven LCH were identified. Of these, the case histories of 16 children who had been treated with pamidronate (PAM) for disease reactivation were analyzed in detail. The median post-PAM therapy follow-up period was 2.8 years (range: 0.9-9.3 years). The median age at commencement of PAM therapy was 9.4 years (range: 2.3-15.0 years). All children had one or more bone lesions but none had risk organ (RO) involvement. In the majority of the children, six courses of PAM were administered at a dose of 1.0 mg/kg/course at 4-week intervals. In 12 of the 16 children, all active lesions including lesions of the skin (n = 3) and soft tissues (n = 3) resolved. Of these children, eight children had no active disease for a median of 3.3 years post-PAM therapy (range: 1.8-9.3 years). Progression-free survival (PFS) was 56.3 ± 12.4% at 3 years. PFS was significantly higher in children with a first reactivation compared with children experiencing a second or subsequent reactivation.

CONCLUSIONS

PAM may be an effective treatment for reactivated LCH with bone lesions. A prospective trial of the efficacy of PAM in recurrent pediatric LCH is warranted.

Outcome of pediatric renal tumor treated using the Japan Wilms Tumor Study-1 (JWiTS-1) protocol: a report from the JWiTS group

PURPOSE

In 1996, the Japan Wilms Tumor Study (JWiTS) group was founded to elucidate the efficacy and safety of the regimen established by the National Wilms Tumor Study (NWTS) group in the USA, and a multicenter cooperative study (JWiTS-1) was started in Japan. This report reviews the results of JWiTS-1.

METHODS

A total of 307 patients with malignant renal tumor were enrolled in the JWiTS-1 study between 1996 and 2005. Central pathological diagnosis and follow-up data were available in 210 cases. The protocol regimens were similar to the NWTS-5 regimens. Clinical stage was classified according to the Japanese Staging System.

RESULTS

Five-year overall survival (OS) rate was 91.1% for nephroblastoma, 72.9% for clear cell sarcoma of the kidney (CCSK), and 22.2% for rhabdoid tumor of the kidney (RTK). In the nephroblastoma patients, 5-year OS was 90.5% for stage I disease, 92.2% for stage II, 90.9% for stage III, 86.7% for stage IV, and 78.7% for stage V.

CONCLUSIONS

The OS of patients in the JWiTS-1 study were comparable with the results of other multicenter studies in the USA and Europe. The outcome for patients with nephroblastoma and CCSK was fair. In contrast, the cure rate for those with RTK was not satisfactory. New treatment strategies are needed for patients with RTK.

Yolk sac tumor but not seminoma or teratoma is associated with abnormal epigenetic reprogramming pathway and shows frequent hypermethylation of various tumor suppressor genes

Germ cell tumors (GCTs) are thought to arise from primordial germ cells (PGCs) that undergo epigenetic reprogramming: erasure of the somatic imprint in the genital ridge, and re-establishment of the sex-specific imprint at gametogenesis in the developing gonad. Previous studies suggested that GCTs show epigenetic patterns reflecting the reprogramming process of PGCs; however, epigenetic alterations of imprinted genes and their relationship with the methylation status of tumor suppressor genes (TSGs) have not been comprehensively studied. We analyzed the methylation status of the H19 and SNRPN differential methylated regions (DMRs) and the promoter region of 17 TSGs, and the expression status of H19, IGF2 and SNRPN in 45 GCTs, and found that 25 and 20 were in the normal and abnormal reprogramming pathways, respectively, defined on the basis of the methylation status of the two DMRs and the anatomical tumor site. The methylation pattern of the H19 and SNRPN DMRs was total erasure in seminomas, mostly physiological in teratomas, and various in yolk sac tumors. There were no correlations between the methylation status of the H19 DMR and mono- or biallelic expression of H19 or IGF2. Furthermore, we found that yolk sac tumors had a higher number of methylated TSGs than seminomas (P < 0.001) teratomas (P = 0.004) or other childhood tumors. While TSG methylation was known to have prognostic implications in various cancers, it did not affect the outcomes of patients with yolk sac tumor, suggesting that mechanisms of TSG methylation may be different between yolk sac tumor and other cancers.

Duplication of paternal IGF2 or loss of maternal IGF2 imprinting occurs in half of Wilms tumors with various structural WT1 abnormalities

The WT1 gene essential for the embryonic kidney development is mutated in 15-25% of Wilms tumors (WTs). To clarify whether genetic subtypes of WT1 abnormalities are correlated with IGF2 or CTNNB1 alterations or clinicopathological characteristics, we performed comprehensive WT1, IGF2, and CTNNB1 analyses of 36 WTs with WT1 abnormalities using single nucleotide polymorphism arrays, and methylation analysis of the IGF2-H19 differentially methylated region. The tumors were classified into three subtypes based on WT1 abnormalities: 13 with WT1 deletion, 12 with WT1 mutation, and 11 with both deletion and mutation. IGF2 alterations were found in 50% (18/36), paternal uniparental disomy (UPD) of 11p13-11p15 in 13 tumors, UPD limited to 11p15 in 3, and loss of IGF2 imprinting in 2. Quantitative RT-PCR analysis showed that tumors with IGF2 alteration had higher levels of IGF2 mRNA than tumors without IGF2 alteration (P = 0.02). WT1 mRNA levels were very low in six of eight WTs with WT1 deletion, whereas four of eight WTs with WT1 mutation or both deletion and mutation showed higher levels of WT1 mRNA than fetal kidneys. WTs with WT1 mutations occurred in younger patients (P < 0.01), and WTs with mutations or both deletion and mutation (12/23) were more frequent in syndromic patients than WTs (1/13) with the deletion (P = 0.02). WTs with WT1 mutations or both deletion and mutation had the triphasic histological-type (15/23; P = 0.03) and CTNNB1 mutation (17/23; P = 0.03) more frequently than WTs with the deletion (2/13 and 4/13). Thus, three WT1 subtypes were correlated with certain genetic and clinicopathological characteristics.

Duplication of the paternal IGF2 allele in trisomy 11 and elevated expression levels of IGF2 mRNA in congenital mesoblastic nephroma of the cellular or mixed type

In a metaphase comparative genomic hybridization and fluorescence in situ hybridization study of 13 congenital mesoblastic nephroma (CMN) tumors, trisomy 11 was found in seven cellular or mixed type tumors, disomy 11 with other chromosome changes in two cellular type tumors, and no chromosome changes in four classical type tumors. Reverse-transcription (RT)-PCR analysis detected the ETV6-NTRK3 fusion transcript in all eight cellular or mixed type tumors examined, but not in four classical type tumors. All seven tumors with trisomy 11 showed duplication of the paternal IGF2 allele, and six cellular or classical type tumors with disomy 11 showed one paternal and one maternal allele of IGF2, analyzing the methylation status of the sixth CTCF site of the H19-differentially methylated region. Allelic expression study using the ApaI/AvaII polymorphism site at exon 9 of IGF2 showed retention of imprinting in all seven tumors examined. Quantitative real-time RT-PCR analysis showed higher expression levels of IGF2 mRNA in three of three cellular type tumors with trisomy 11, in one cellular type tumor with disomy 11, and in three of four classical tumors than in fetal kidneys or normal kidney tissues. Thus, duplicated paternal IGF2 resulted in elevated IGF2 mRNA levels, and may provide CMN or its precursor cells with a proliferative advantage. The mechanism explaining that some cellular or classical type tumors with disomy 11 also showed elevated IGF2 mRNA levels remains unresolved. IGF2 clearly plays an important role in the tumorigenic process of CMN, although it is difficult to assess its exact role.

Genetic and epigenetic alterations on the short arm of chromosome 11 are involved in a majority of sporadic Wilms' tumours

Wilms' tumour is one of the most common solid tumours of childhood. 11p13 (WT1 locus) and 11p15.5 (WT2 locus) are known to have genetic or epigenetic aberrations in these tumours. In Wilms' tumours, mutation of the Wilms tumour 1 (WT1) gene at the WT1 locus has been reported, and the WT2 locus, comprising the two independent imprinted domains IGF2/H19 and KIP2/LIT1, can undergo maternal deletion or alterations associated with imprinting. Although these alterations have been identified in many studies, it is still not clear how frequently combined genetic and epigenetic alterations of these loci are involved in Wilms' tumours or how these alterations occur. To answer both questions, we performed genetic and epigenetic analyses of these loci, together with an additional gene, CTNNB1, in 35 sporadic Wilms' tumours. Loss of heterozygosity of 11p15.5 and loss of imprinting of IGF2 were the most frequent genetic (29%) and epigenetic (40%) alterations in Wilms' tumours, respectively. In total, 83% of the tumours had at least one alteration at 11p15.5 and/or 11p13. One-third of the tumours had alterations at multiple loci. Our results suggest that chromosome 11p is not only genetically but also epigenetically critical for the majority of Wilms' tumours.

Association of 11q loss, trisomy 12, and possible 16q loss with loss of imprinting of insulin-like growth factor–II in Wilms tumor

We evaluated the WT1 and IGF2 status and performed chromosome and/or comparative genomic hybridization analysis in 43 tumor samples from patients with Wilms tumor. On this basis, we classified them into 4 groups: WT1 abnormality, loss of heterozygosity (LOH) of IGF2, loss of imprinting (LOI) of IGF2, and retention of imprinting (ROI) of IGF2, which were seen in 12%, 30%, 16%, and 42% of the tumors, respectively. Patients in the LOI group were older than those in other groups (P < 0.01), and tumors in the WT1 group had fewer cytogenetic changes than did those in the other groups (P < 0.01). It was found that 11q- and +12 were more frequent in the LOI group than in the WT1+LOH+ROI group (P < 0.01 and P < 0.01). There was no difference in the incidence of 16q- between the LOI group and the other groups; however, when we excluded 16 tumors with LOH on 11p15, 16q- tended to be more frequent in the LOI group than in the WT1+ROI group (P = 0.06). The association of 11q- or +12 with LOI of IGF2 found in the present study suggests that many tumors with no WT1 abnormalities need overexpression of IGF2 together with biallelic inactivation of the tumor-suppressor gene on 11q and/or overexpression of growth-promoting genes on chromosome 12. The 11q gene may code for one of the proteins that constitute a CTCF insulator complex, and its mutation, deletion, or haploinsufficiency may cause insulator abnormalities that might lead to LOI of IGF2.

Telangiectatic focal nodular hyperplasia of the liver in the perinatal period: case report

We report a case of congenital telangiectatic focal nodular hyperplasia, a rare variant form of the disease. The patient was a 2-month-old boy whose parents noticed abdominal distention about 2 weeks after birth, and ultrasonogram revealed a large mass in the liver. He underwent right lobectomy, and gross findings showed an ill-defined mass without any central scar. Histologic findings demonstrated proliferating hepatocytes without atypia arranged in cords of 1- or 2-cell thickness with marked sinusoidal dilatation and extramedullary hematopoiesis. In addition, a significantly increased Ki-67 labeling index in the tumor compared with non-tumor liver cells, and cytogenetic analysis of 23 G-banded metaphase preparations revealed 3 abnormal karyotypes, suggesting hyperplastic or neoplastic features. To the best of our knowledge, the present case is only the third documented case of congenital telangiectatic focal nodular hyperplasia.

Domain-specific function of ShcC docking protein in neuroblastoma cells

ShcC is a family member of the Shc docking proteins that possess two different phosphotyrosine-binding motifs and conduct signals as Grb2-binding substrates of various receptor tyrosine kinases. We have recently shown that some neuroblastoma cell lines, such as NB-39-nu cells, express a protein complex of hyperphosphorylated ShcC and anaplastic lymphoma kinase (ALK), which is self-activated by gene amplification. Here, we demonstrate that the expression of a mutant ShcC lacking Grb2-binding sites, 3YF-ShcC, significantly impaired the survival, differentiation and motility of NB-39-nu cells by blocking the ERK and Akt pathways. On the other hand, cells overexpressing ShcC or 3YF-ShcC, but not a mutant ShcC that lacks SH2, showed decreased anchorage independency and in vivo tumorigenicity, suggesting a novel ShcC-specific suppressive effect through its SH2 domain on cell transformation. Notably, overexpression of ShcC suppressed the sustained phosphorylation of Src family kinase after cell detachment, which might be independent of phosphorylation of Grb2-binding site. It was indicated that the Src/Fyn-Cas pathway is modulated as a target of these suppressive effects by ShcC. Reciprocal change of ShcC expression and phosphorylation observed in malignant neuroblastoma cell lines might be explained by these phosphotyrosine-dependent and -independent functions of ShcC.

Cryptic insertion and translocation or nondividing leukemic cells disclosed by FISH analysis in infant acute leukemia with discrepant molecular and cytogenetic findings

Of 51 infants with acute leukemia, 13 (25%) had contradictory findings on 11q23/MLL rearrangements that were analyzed by cytogenetic and Southern blot methods: seven had rearranged MLL and normal karyotype, four had rearranged MLL and abnormal karyotype with no 11q23 translocation, and two had germline MLL and 11q23 translocations. Fluorescent in situ hybridization (FISH) analysis using an MLL probe that was performed to elucidate the discrepancy disclosed the presence of normal dividing cells and nondividing leukemic cells in the same bone marrow in five patients, and cryptic insertion or translocation in another five. Subsequent FISH and reverse transcription-polymerase chain reaction analysis identified the MLL-AF10, MLL-AF4, or MLL-AF1q fusions that were produced by the cryptic rearrangements in four of the five patients. In the remaining three patients, the breakpoint of 11q23 translocation was located distal to the MLL locus in one, and the discrepancy was unresolved in two. Thus, FISH should complement cytogenetic analysis when cytogenetic and molecular genetic findings are contradictory in infant leukemia, and when infant leukemia does not show 11q23 translocations or other specific translocations including t(7;12), t(1;22), etc that are recurrently found in infant leukemia.

Significant reduction of WT1 gene expression, possibly due to epigenetic alteration in Wilms' tumor

WT1 at 11p13 is a tumor suppressor gene, an aberration of which causes Wilms' tumor (WT). Since WT1 expression is reduced in a certain proportion of WTs and its mutation is found only in 10-20% of WTs, we examined WT1 gene silencing due to epigenetic alteration in a total of 22 WTs. WT1 expression was significantly reduced in half of WTs without any mutation in the WT1 gene itself, suggesting that the reduction of expression was possibly epigenetic. We found promoter hypermethylation in one WT with loss of heterozygosity (LOH) and showed that promoter methylation reduced reporter gene activity by a reporter assay. These data suggested that methylation was an epigenetic mechanism leading to WT1 silencing and that the expression-reduced allele by hypermethylation combined with LOH was consistent with the revised two-hit model. In addition, as the beta-catenin mutation is frequently associated with the WT1 mutation, the association of WT1 silencing with the beta-catenin mutation was also investigated. beta-catenin mutated in only one WT without WT1 silencing, suggesting that the beta-catenin mutation was not associated with the reduction of WT1 expression.

Low natural killer activity and central nervous system disease as a high-risk prognostic indicator in young patients with hemophagocytic lymphohistiocytosis

BACKGROUND

Familial hemophagocytic lymphohistiocytosis HLH (FHL) is fatal, unless patients are rescued with hematopoietic stem cell transplantation (SCT). Although the molecular identification of FHL now is possible at least in part from perforin gene study, many cases escape detection or never are tested due to the lack of specific hallmarks, making diagnosis difficult. To the authors' knowledge, it remains to be determined whether persistently low natural killer cell (NK) activity and a high incidence of central nervous system (CNS) disease increase the probability of FHL.

METHODS

The authors analyzed 42 HLH patients age < 2 years, 13 of whom developed overt CNS disease and 5 of whom demonstrated persistently deficient NK activity (Group 1). The remaining 24 patients had no CNS disease and had NK activity of moderate decrease to within the normal range (Group 2).

RESULTS

In Group 1, CNS symptoms were detected in 6 cases within 1 month and between 4.5-9 months in 6 other patients. In these cases, spotty lesions demonstrating a high T2 signal in the white matter were noted on brain magnetic resonance imaging. The survival was significantly poor for patients in Group 1 unless they were rescued with SCT, which was performed in 5 of the 13 patients with CNS disease and in all 5 patients with persistent NK activity deficiency. SCT was successful in 9 patients, with no CNS sequelae reported after the transplantation. Conversely, the prognosis of the 24 patients in Group 2 was better and only 1 patient required SCT.

CONCLUSIONS

Very young HLH patients (age < 2 years) who are at high risk of fatal FHL with persistently deficient NK activity and/or overt CNS disease require appropriate SCT to reverse CNS disease and achieve a complete cure.

Mutations/deletions of the WT1 gene, loss of heterozygosity on chromosome arms 11p and 11q, chromosome ploidy and histology in Wilms' tumors in Japan

Incidence rates of Wilms' tumor (WT) markedly differ in East Asian and Caucasian children. In the present study, we examined WT1 deletions/mutations and loss of heterozygosity (LOH) on 11p and 11q in a large number of WTs and compared our findings with those from 4 series of Caucasian WTs. Incidence rates of the subtle WT1 mutation in 3 of the 5 series of sporadic and unilateral WTs including ours were 4.3-6.2% and similar. However, gross homozygous WT1 deletion was more frequent in our series than in some others. In addition, our series tended to show a higher incidence of LOH limited to 11p13 and a lower incidence of LOH including 11p15 than the Caucasian one. These findings indicate some genetic differences in WT between the 2 regions. One of the 4 Caucasian series reported a correlation of germinal WT1 mutation with the predominantly stromal histology. The present study not only confirms the correlation of germinal WT1 deletion/mutation with predominant stromal histology but also establishes a correlation with somatic WT1 deletion/mutations with predominant stromal histology. While WTs with WT1 abnormalities usually showed pseudodiploidy and predominant stromal histology, those without WT1 abnormalities showed various chromosome numbers and histologic subtypes.

Correlation of chromosome abnormalities with presence or absence of WT1 deletions/mutations in Wilms tumor

Of 40 Wilms tumors with chromosome abnormalities, 6 were hypodiploid, 10 were pseudodiploid, 7 were hyperdiploid with 47 to 49 chromosomes, and 17 were hyperdiploid with 50 or more chromosomes, mostly including +12. WT1 deletions/mutations were found in one hypodiploid, eight pseudodiploid, and one hyperdiploid (47-49 chromosomes) tumor, but in none of the hyperdiploid (> or =50 chromosomes) tumors. Of the 10 tumors with WT1 abnormalities, 6 had a homozygous WT1 deletion, 1 had a nonsense WT1 mutation and loss of heterozygosity at 11p, 1 had an intragenic hemizygous WT1 deletion without detectable WT1 mutation, and 2, which occurred in Wilms tumor-aniridia-genitourinary abnormalities-mental retardation syndrome patients, had a hemizygous deletion and a missense or frameshift mutation of WT1. Six of the nine tumors with homozygous or hemizygous WT1 deletions had chromosome aberrations involving chromosome band 11p13 in one of the two chromosomes 11. While one hypodiploid and one pseudodiploid patient died of the disease, and one hyperdiploid (47-49 chromosomes) patient was alive in nonremission, all hyperdiploid (> or =50 chromosomes) patients had no evidence of disease at the last follow-up. Our data show that chromosome aberrations are closely correlated to WT1 abnormalities and suggest that hyperdiploid (> or =50 chromosomes) Wilms tumors may be characterized by the absence of WT1 abnormalities and possibly also by a favorable prognosis.

Long survivors with Ki-1 lymphoma having t(2;5) (p23;q35). Does the presence or absence of t(2;5) influence the prognosis of patients with Ki-1 lymphoma?

We experienced three patients with CD30+ diffuse large cell lymphoma having chromosomal abnormalities. The first patient was an 8-year-old girl with bilateral cervical lymphadenopathy. A biopsy of a cervical lymph node revealed diffuse large cell lymphoma (stage III), positive for CD30 and a chromosomal abnormality, t(2;5). She attained a remission and is now in complete remission 108 months after diagnosis, despite frequent relapses. The second patient was a 13-year-old boy with right axillar and supraclavicular lymph-node adenopathy. A biopsy of a cervical lymph node revealed diffuse large cell lymphoma (stage III), positive for CD30 and a chromosomal abnormality, t(2;5). He attained remission and was in continuous first remission 112 months after diagnosis. The third patient was an 11-year-old boy with fever and bilateral cervical lymph node revealed diffuse large cell lymphoma (stage III), positive for CD30 and chromosomal abnormality without t(2;5). He showed a very aggressive clinical course. Only the patients with Ki-1 lymphoma having t(2;5) survived over 100 months from the diagnosis, despite the advanced stage of the disease. These findings and a review of the literature showed that the presence or absence of t(2;5) may influence the outcome of Ki-1 lymphoma.

[Childhood acute promyelocytic leukemia treated with all-trans retinoic acid]

We treated two children with acute promyelocytic leukemia (APL) in whom complete remission was successfully induced by oral administration of all-trans retinoic acid (ATRA). We followed these patients with conventional chemotherapy. The first patient has remained in continuous complete remission. However, the other patient relapsed during the maintenance therapy and died of progressive disease in spite of a second treatment with ATRA and chemotherapy. From a clinical point of view, the latter case had a hyperleukocytosis on admission. Also morphologically speaking, this patient had a different M3 variant than the first case. There are two major isoforms of PML/RAR alpha transcripts, so called short and long type transcripts, according to the breakpoints in the PML genes. In the first case the "long type' isoform was detected by reverse transcriptase polymerase chain reaction (RT/PCR) amplification. On the other hand the "short type' isoform was observed in the latter case. Also the second case became PCR positive at relapse, although the detectable isoform was negative during remission. The "short type' isoform may be related to the poor prognosis and RT/PCR analyses may be a powerful to detect early relapse.

Acute lymphoblastic leukemia and non-Hodgkin's lymphoma with mediastinal mass--a study of 23 children; different disorders or different stages?

Mediastinal tumor was found in both acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). Most cases showed the T-cell phenotype. We query whether these two diseases are in fact different disorders or merely different stages of the same disease. Twelve ALL patients with a mediastinal mass and eleven NHL patients with a mediastinal mass under 15 years of age were studied with respect to cytogenetics, immunophenotype, genotype and clinical features. Clonal chromosome abnormalities were found in 75% (9/12) of the ALL patients and 100% (11/11) of the NHL patients. Of the 20 patients with chromosome abnormalities, 12 (60%) had translocations involving 14q11-13 and 7q35 (8 ALL, 4 NHL). t(9;17)(q34;q23) was found only in 3 patients with NHL. All showed the T-cell phenotype except two, who had none of the chromosomal abnormalities frequently detected in T cell ALL/NHL. In T-cell patients, immunophenotypical staging of ALL showed a predominance of early and common thymocyte phenotypes while that of NHL showed a predominance of common thymocyte phenotypes. All 7 of the T-cell patients examined showed rearrangements of the T-cell receptor beta chain gene. On the other hand, two non-T-cell, non-B-cell patients showed no rearrangement. There were no apparent clinical differences between ALL and NHL patients in age (median 8.6 vs 8.9 years), sex ratio (F/M 9/3 vs 7/4) or in the rate of complete remission (90% vs 100%). Our study demonstrated no relevant clinical, prognostic, or immunophenotypic differences between ALL and NHL with mediastinal mass.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical characteristics and treatment results of acute promyelocytic leukemia in children (Children's Cancer and Leukemia Study Group)]

The clinical characteristics and treatment outcome in 40 children with acute promyelocytic leukemia (APL) treated at institutions participating in the Children's Cancer and Leukemia Study Group (CCLSG) were studied retrospectively. The median age at diagnosis was 8 years old. Bleeding diathesis was the predominant presenting symptom (90%), associated with laboratory findings of disseminated intravascular coagulation. Hepatomegaly, splenomegaly and lymphadenopathy were observed in 35%, 10%, and 15% of the cases, respectively. The median WBC count was 4.25 x 10(9)/l. Anemia (hemoglobin < 8 g/dl) and thrombocytopenia (< 30 x 10(9)/l) were present in more than half of the patients. Cytogenetic studies demonstrated the characteristic 15; 17 translocation in about 90% of the patients analyzed. Induction therapy consisted of cytosine arabinoside and an anthracycline, with or without other agents. Twenty-nine patients (73%) achieved complete remission (CR) while early fatal hemorrhage was the predominant cause of induction failure. The survival rates continued to decrease (28% at 3 years, 24% at 5 years, and 7.9% at 10 years) due to late marrow relapses. Anthracycline cardiotoxicity was fatal in three patients in remission. These clinical features of childhood APL should be taken into account in the development of new protocols.

[Primary myelofibrosis in an infant--a case report and review of the literature]

Primary myelofibrosis (PMF) is regarded as a chronic myeloproliferative disorder. It is characterized by marrow fibrosis, leukoerythroblastosis, tear drop erythrocytes and extramedullary hematopoiesis. Most patients are in their late 50s when first diagnosed. Pediatric PMF is said to be quite rare. Here describe a female infant with PMF. The patient was born on Aug. 7, 1991. The pregnancy and delivery were uneventful. Hepatomegaly was noted soon after birth. Combined blood counts showed polycythemia and leukocytosis. It was thought to be extramedullary hematopoiesis due to intrauterine infection. She was followed up in another hospital, but since her condition was unchanged she was admitted to our hospital for further medical examinations at age 7 months. On the peripheral blood smear, there were tear drop erythrocytes, normoblasts and early myeloid elements. Repeated bone marrow aspirations were dry taps. This case presented the classical findings of fibrosis of the bone marrow on bone marrow biopsy. She is in good health without any therapy until now. A review of 7 cases of PMF, including our case, in Japanese children was made and discussed in comparison to adult cases.

[A multi-institutional study on the efficacy and toxicity of imipenem/cilastatin sodium in severe infections complicating hematological diseases and cancers in children. Study Group of Infectious Diseases in Pediatric Hematology/Oncology in Hokkaido]

A multi-institutional study was conducted between September 1990 and April 1992 to evaluate the efficacy and toxicity of imipenem/cilastatin sodium (IPM/CS) in severe infections in cases of granulocytopenia in children with hematological diseases and cancers. A total of 60 episodes of infection were treated with the drug, and an overall efficacy rate of 80% (48/60) was obtained. The efficacy rate in patients who were positive for Endospecy test was 90.0%. A group of patients who had previously received other antibiotics showed an efficacy rate of 79.2%, while the patients who had not received previous antibiotic treatment showed an efficacy rate of 80.6%. The difference between the 2 groups was statistically insignificant, however. Granulocyte counts appeared to have influence on the efficacy of the drug, but the influence was not strong. Three patients had nausea, vomiting and/or diarrhea, and 2 other patients showed abnormal liver function test parameters though they recovered soon after the cessation of the drug treatment. From these results, we have concluded that IPM/CS is an effective antibiotic for treatment of severe infections with hematological diseases and cancers in children.

[Analysis of cytoplasmic antigens in acute leukemia by flow cytometry]

The expression of cytoplasmic antigens in 77 cases of acute leukemia were analyzed by flow cytometry using the following monoclonal antibodies: CD3, CD22, anti-myeloperoxidase (MPO-7) and anti-mu-heavy chain. CD22 antigen was detected in the cytoplasm of all non-T-ALL patients excluding one not-tested patient. In two patients with unclassified ALL, surface CD22 antigen was not expressed but cytoplasmic CD22 antigen was strongly expressed. Three out of 9 patients with common ALL were cytoplasmic mu-heavy chain-positive, so these patients were diagnosed as Pre-B ALL. In four out of 8 patients with T-ALL, CD3 antigen was not expressed on the cell surface membrane. However all of T-ALL patients excluding one non-tested patient were cytoplasmic CD3-positive. The cytoplasmic expression of myeloperoxidase antigen was detected in twenty out of 21 patients with acute non-lymphoblastic leukemia (ANLL). One megakaryocytic leukemia patient was MPO-negative. In two ANLL patients, the percentage of MPO for conventional cytochemical staining was undetectable or low, but MPO antigens were positive (77% and 70%) for flow cytometric analysis. All of 46 non-T ALL patients were cytoplasmic MPO-negative, however 4 out of 10 T-ALL patients were cytoplasmic MPO-positive. The study proved that the analysis of cytoplasmic CD3, CD22, mu-chain and MPO antigens were very useful to define the cell lineage of leukemia and to classify ALL and ANLL. It is necessary to study further whether the expression of MPO in the cytoplasm of T-ALL was non-specific reaction or whether MPO precursors are expressed in the cytoplasm of T-ALL.

Cytogenetic characteristics of childhood non-Hodgkin lymphoma

Cytogenetic studies were performed successfully on 24 patients with non-Hodgkin lymphoma (NHL) who were younger than 15 years of age. Of these, 22 patients (92%) had abnormal clones. With respect to histologic findings, 3 (25%) of the 12 patients with lymphoblastic lymphoma had 14q11 translocations and 2 (17%) had t(9;17) (q34;q23). Four (80%) of the five patients with small non-cleaved cell lymphoma had t(8;14)(q24;q32). With respect to immunologic findings, four (44%) of the nine patients with T-cell lymphoma had abnormalities consisting of 14q11 and 7q36 translocations, in which the T-cell receptor genes resided. Three (33%) of the patients with T-cell lymphoma had t(9;17)(q34;q23). However, three (43%) of the seven patients with B-cell lymphoma had t(8;14) (q23;q32), and two (29%) of the patients with B-cell lymphoma had an extra i(11q) chromosome with a resultant 11q tetrasomy. Non-T-cell non-B-cell lymphomas, which occurred in 21% of all patients, showed various chromosomal abnormalities. This study demonstrated that, in childhood NHL, karyotype correlates closely with immunophenotype, clinical features, and histologic findings.

Analysis of 13 postmortem examinations with regard to the effect of chemotherapy on neuroblastoma patients

Thirteen postmortem examinations on neuroblastoma patients were reviewed clinicopathologically. Commonly found metastatic sites were bone, liver and lung. The introduction of massive doses of cyclophosphamide and cisplatinum into chemotherapy protocol markedly reduced the tumor burden: no tumor focus in liver or lung, small tumor burden in bone. Lymph node metastasis remained, however, and was refractory to the chemotherapy. The intensive chemotherapy caused severe side effects: interstitial or bacterial pneumonia and intrathecal bleeding, which sometimes proved fatal. Such side effects must, therefore, be carefully controlled in order to maximize the survival rate.