Characteristics of Li-Fraumeni Syndrome in Japan; A Review Study by the Special Committee of JSHT.

Li-Fraumeni syndrome (LFS) is a hereditary cancer predisposition syndrome, and the majority of patients with LFS have been identified with germline variants in the p53 tumor suppressor (TP53) gene. In the past three decades, considerable case reports of TP53 germline variants have been published in Japan. To the best of our knowledge, there have been no large-scale studies of Japanese patients with LFS. In this study, we aimed to identify Japanese patients with TP53 germline variants and to reveal the characteristics of LFS in Japan. We collected reported cases by reviewing the medical literature and cases diagnosed at the institutions of the authors. We identified 68 individuals from 48 families with TP53 germline pathogenic or likely pathogenic variants. Of the 48 families, 35 (72.9%) had missense variants, most of which were located within the DNA-binding loop. A total of 128 tumors were identified in the 68 affected individuals. The 128 tumor sites were as follows: breast, 25; bones, 16; brain, 12; hematological, 11; soft tissues, 10; stomach, 10; lung, 10; colorectum, 10; adrenal gland, 9; liver, 4; and others, 11. Unique phenotype patterns of LFS were shown in Japan in comparison to those in a large national LFS cohort study in France. Above all, a higher frequency of patients with stomach cancer was observed in Japanese TP53 germline variant carriers. These results may provide useful information for the clinical management of LFS in Japan.

Medical guidelines for Li-Fraumeni syndrome 2019, version 1.1.

Li-Fraumeni syndrome (LFS) is a hereditary tumor that exhibits autosomal dominant inheritance. LFS develops in individuals with a pathogenic germline variant of the cancer-suppressor gene, TP53 (individuals with TP53 pathogenic variant). The number of individuals with TP53 pathogenic variant among the general population is said to be 1 in 500 to 20,000. Meanwhile, it is found in 1.6% (median value, range of 0-6.7%) of patients with pediatric cancer and 0.2% of adult patients with cancer. LFS is diagnosed by the presence of germline TP53 pathogenic variants. However, patients can still be diagnosed with LFS even in the absence of a TP53 pathogenic variant if the familial history of cancers fit the classic LFS diagnostic criteria. It is recommended that TP53 genetic testing be promptly performed if LFS is suspected. Chompret criteria are widely used for the TP53 genetic test. However, as there are a certain number of cases of LFS that do not fit the criteria, if LFS is suspected, TP53 genetic testing should be performed regardless of the criteria. The probability of individuals with TP53 pathogenic variant developing cancer in their lifetime (penetrance) is 75% for men and almost 100% for women. The LFS core tumors (breast cancer, osteosarcoma, soft tissue sarcoma, brain tumor, and adrenocortical cancer) constitute the majority of cases; however, various types of cancers, such as hematological malignancy, epithelial cancer, and pediatric cancers, such as neuroblastoma, can also develop. Furthermore, approximately half of the cases develop simultaneous or metachronous multiple cancers. The types of TP53 pathogenic variants and factors that modify the functions of TP53 have an impact on the clinical presentation, although there are currently no definitive findings. There is currently no cancer preventive agent for individuals with TP53 pathogenic variant. Surgical treatments, such as risk-reducing bilateral mastectomy warrant further investigation. Theoretically, exposure to radiation could induce the onset of secondary cancer; therefore, imaging and treatments that use radiation should be avoided as much as possible. As a method to follow-up LFS, routine cancer surveillance comprising whole-body MRI scan, brain MRI scan, breast MRI scan, and abdominal ultrasonography (US) should be performed immediately after the diagnosis. However, the effectiveness of this surveillance is unknown, and there are problems, such as adverse events associated with a high rate of false positives, overdiagnosis, and sedation used during imaging as well as negative psychological impact. The detection rate of cancer through cancer surveillance is extremely high. Many cases are detected at an early stage, and treatments are low intensity; thus, cancer surveillance could contribute to an improvement in QOL, or at least, a reduction in complications associated with treatment. With the widespread use of genomic medicine, the diagnosis of LFS is unavoidable, and a comprehensive medical care system for LFS is necessary. Therefore, clinical trials that verify the feasibility and effectiveness of the program, comprising LFS registry, genetic counseling, and cancer surveillance, need to be prepared.

Roles of AML1/RUNX1 in T-cell malignancy induced by loss of p53.

AML1/RUNX1 is a frequent target of chromosome translocations and mutations in myeloid and B-cell leukemias, and upregulation of AML1 is also observed in some cases of T-cell leukemias and lymphomas. This study shows that the incidence of thymic lymphoma in p53-null mice is less frequent in the Aml1(+/-) than in the Aml1(+/+) background. AML1 is upregulated in p53-null mouse bone-marrow cells and embryonic fibroblasts. In the steady state, p53 binds to and inhibits the distal AML1 promoter. When the cells are exposed to stresses, p53 is released from the distal AML1 promoter, resulting in upregulation of AML1. Overexpression of AML1 stimulates T-lymphocyte proliferation. These results suggest that upregulation of AML1 induced by loss of p53 promotes lymphoid-cell proliferation, thereby inducing lymphoma development.

Evaluation of the safety and efficacy of liposomal amphotericin B (L-AMB) in children.

A multicenter, uncontrolled clinical study has been conducted to evaluate the safety, efficacy, and pharmacokinetics of liposomal amphotericin B (L-AMB) in children. In this article, the safety and efficacy of L-AMB are discussed. Subjects were diagnosed with invasive fungal infection (definitely diagnosed cases), possible fungal infection (clinically diagnosed cases), and febrile neutropenia with suspected fungal infection (febrile neutropenia cases). Of the 39 subjects treated with L-AMB, 18 received a definite (11) or clinical (7) diagnosis of invasive fungal infection. In these subjects, excluding one unevaluable subject, L-AMB was effective in nine out of 17 subjects(52.9%). Of 12 febrile neutropenia cases, improvement in clinical symptoms, etc., was observed for six but these were excluded from the efficacy analysis because they concomitantly used medications that may have affected efficacy. The causative fungus was identified in four out of 39 subjects and confirmed to be eliminated by treatment with L-AMB in one subject. Adverse events possibly related to L-AMB (adverse drug reactions) were reported in 36 out of 39 subjects (92.3%). The most commonad verse drug reaction was decreased potassium in 20 out of 39 subjects (51.3%), but all these subjects recovered with appropriate treatment, for example potassium supplementation.In a Japanese Phase II clinical study of adult patients, the incidence of adverse drug reactions was 95.3%(82/86 subjects) and the efficacy was 63.6% (42/66). Taken together, these data indicate that the safety and efficacy of L-AMB are almost the same in pediatric and adult patients.

A 9-month-old infant with acquired idiopathic thrombotic thrombocytopenic purpura caused by inhibitory IgG-autoantibody to ADAMTS13.

Although acquired idiopathic thrombotic thrombocytopenic purpura (ai-TTP) is rare in children, the authors present the case of a 9-month-old boy with ai-TTP showing severe deficiency of ADAMTS13 activity by its inhibitory IgG-autoantibody (4.8 Bethesda units/mL). Plasma exchange therapy was clinically effective but transient. Deficient activity of ADAMTS13 with the presence of its inhibitor persisted for 7 months after the initial diagnosis. However, other laboratory findings improved gradually with steroid (pulse) therapy. The hitherto insufficiently characterized clinical settings of ai-TTP during early childhood underscore the importance of measuring ADAMTS13 activity and its inhibitors for differential diagnosis in patients with thrombocytopenia of unknown etiology.

Nationwide retrospective review of hematopoietic stem cell transplantation in children with refractory Langerhans cell histiocytosis.

The efficacy of and indications for hematopoietic stem cell transplantation (HSCT) in pediatric Langerhans cell histiocytosis (LCH) remain undetermined. This retrospective study analyzed 30 children with refractory LCH who underwent HSCT in Japan between 1996 and 2014. Eleven patients received a myeloablative conditioning (MAC) regimen, while 19 patients received a reduced-intensity conditioning (RIC) regimen. Among the 26 patients with complete data, 23 patients had risk organ (RO) involvement during clinical course. Disease status at HSCT was no active disease (NAD) (4), active disease-regression (AD-r) (2), active disease-stable (AD-s) (4), and active disease-progressive (AD-p) (16). Seventeen of the 30 patients (57%) were alive with a median follow-up of 433 days (range 9-5307) after HSCT. Death occurred within 3 months after HSCT in eight of 13 patients. RIC and MAC patients were similar in both overall survival (OS) (56.8% vs. 63.6%, respectively, p = 0.789) and failure-free survival (56.8% vs. 54.6%, respectively, p = 0.938). Regarding disease status at HSCT, the six patients with NAD/AD-r experienced better outcomes than the 20 with AD-s/AD-p (5-year OS, 100% vs. 54.5%, respectively, p = 0.040). Disease state at the time of HSCT was the most important prognostic factor.

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.

Neurodegenerative central nervous system disease as late sequelae of Langerhans cell histiocytosis. Report from the Japan LCH Study Group.

Clinical features, brain magnetic resonance imaging findings and EDSS scores of 11 patients with neurodegenerative central nervous system Langerhans cell histiocytosis were analyzed in Japan. All patients initially had multi-system-type Langerhans cell histiocytosis; 8 at 1-2 years of age and 3 at a later age. Neurodegenerative central nervous system Langerhans cell histiocytosis disease developed after a median time interval of 3.9 years from initial diagnosis. With a median follow-up of 4.5 years, 6 patients showed progression of disease with an EDSS score >3. This study demonstrates the importance of early detection of neurodegenerative central nervous system Langerhans cell histiocytosis by brain magnetic resonance imaging, particularly in the follow-up of patients who developed multi-system-type Langerhans cell histiocytosis in early infancy.

Intensification of induction therapy and prolongation of maintenance therapy did not improve the outcome of pediatric Langerhans cell histiocytosis with single-system multifocal bone lesions: results of the Japan Langerhans Cell Histiocytosis Study Group-02 Protocol Study.

Langerhans cell histiocytosis (LCH) with single-system (SS) multifocal bone (MFB) lesions is rarely fatal, but patients may experience relapses and develop LCH-associated sequelae. To evaluate effect on outcomes of pediatric multifocal LCH, we tested a treatment protocol modified from the Japan Langerhans Cell Histiocytosis Study Group (JLSG)-96 study. We assessed the outcomes of all consecutive newly diagnosed pediatric patients with LCH with SS-MFB lesions who were treated with JLSG-02 protocol in 2002-2009. JLSG-02 was modified from JLSG-96 as follows: increased prednisolone dosage at the induction phase and extension of maintenance therapy duration from 24 to 48 weeks. In total, 82 patients with a median follow-up duration of 8.0 years were eligible for analysis. At 6 weeks, 92.7% responded to induction; however, 27.6% of responders experienced relapses. In total, 4.8% developed central nervous system-related sequelae, including central diabetes insipidus and neurodegeneration, which were associated with relapse. None of the patients died. The 5-year event-free survival rates were not different between JLSG-02 and -96 cohort (66.7 vs. 65.1%; p = 0.697). Modification of previous treatment protocol did not contribute to improvement of outcomes in LCH with SS-MFB lesions.

Use of recombinant activated factor VII to control bleeding in a young child with qualitative platelet disorder: a case report.

Defects of platelet adhesion, aggregation, secretion, or procoagulant activities can lead to bleeding diathesis of variable severity. We used recombinant activated factor VII (rFVIIa) in the treatment of uncontrolled epistaxis in a patient with a qualitative platelet disorder. We aimed to assess the efficacy of a single rFVIIa dose (100 microg/kg) in the control of mild and severe refractory epistaxis, and evaluate the influence of rFVIIa on markers of platelet adhesion and aggregation during a period of hematological stability (i.e. non-bleeding, no medication). The efficacy study showed mild episodes of epistaxis could be successfully managed using a single rFVIIa (100 microg/kg) dose; however, severe bleedings were not well controlled, and platelet transfusion was required to achieve hemostasis. Hematological investigations showed ADP-induced and collagen-induced platelet aggregation increases from 20 to 34% and 16 to 30%, respectively, following rFVIIa administration. There were no differences between pre-dose and post-dose concentrations of membrane glycoproteins. rFVIIa may therefore induce platelet aggregation by activating a glycoprotein-independent aggregation pathway. rFVIIa may have a role in managing mild bleeding episodes not controlled using conventional measures in patients with a qualitative platelet disorder. Further research is needed to determine the mechanism of action, efficacy, and safety of rFVIIa in this population.

Intensified and prolonged therapy comprising cytarabine, vincristine and prednisolone improves outcome in patients with multisystem Langerhans cell histiocytosis: results of the Japan Langerhans Cell Histiocytosis Study Group-02 Protocol Study.

The JLSG-96 study reported very low mortality rates for children newly diagnosed with multifocal Langerhans cell histiocytosis (LCH). The JLSG-02 study was performed to further improve the prognosis from 2002 to 2009. The present study compared the therapeutic results of these two studies in terms of multisystem disease. All patients were treated with 6 weeks of the Induction A regimen, comprising cytarabine, vincristine and prednisolone, followed by maintenance therapy. Poor responders to Induction A were switched to Induction B. JLSG-02 has been revised from JLSG-96 in the following respects: prednisolone dosage during Induction A increased; duration of maintenance therapy extended from 24 to 48 weeks; cyclosporine introduced to Induction B for progressive disease. One hundred forty-seven children with multisystem LCH were evaluated. Of these, 84 were positive for risk of organ involvement (RO) and 63 were RO-negative. At the 6-week point, 76.2 % of RO+ and 93.7 % of RO- patients responded to Induction A. Five-year event-free survival (EFS) was 46.2 % [95 % confidence (CI), 35.5-56.9] for RO+ and 69.7 % (58.4-81.1) for RO-, which was significantly superior to that in JLSG-96 [26.8 % (13.3-40.4) and 38.9 % (16.4-61.4), respectively]. The intensified induction and prolonged maintenance regimens in JLSG-02 improved EFS in patients with multisystem LCH.

Unusual chromaffin cell differentiation of a neuroblastoma after chemotherapy and radiotherapy: report of an autopsy case with immunohistochemical evaluations.

Neuroblastomas are derived from neural crest cells that are capable of multilineage differentiation. Ganglionic neuronal differentiation of childhood neuroblastoma is seen with increasing age, leading to more differentiated tumors called ganglioneuroblastomas or ganglioneuromas. Despite the fact that neuroblastomas most often arise from the adrenal medulla, chromaffin-cell differentiation in neuroblastomas is not widely recognized. Tumor cells with a chromaffin-cell nature have only been detected using histochemical techniques in neuroblastoma cell lines or focal areas of certain in vivo tumors. We describe a neuroblastoma that exhibited an unusual differentiation toward chromaffin cells in a patient that had been treated with surgery, intensive chemotherapy, and radiotherapy. Although a biopsy specimen of the retroperitoneal primary tumor was extensively necrotic, possibly because of a previous chemotherapy regimen, surgically resected metastatic tumors of bilateral ovaries were viable and diagnosed as poorly differentiated neuroblastomas according to the International Neuroblastoma Pathology Classification system. However, metastatic tumors of bilateral lungs examined at the time of autopsy exhibited histologic features similar to those of a pheochromocytoma/paraganglioma, and immunohistochemical examinations demonstrated that these tumors were composed of extra-adrenal chromaffin cells. This case confirms that neuroblastomas in childhood can transform into pheochromocytoma/paraganglioma-like tumors under special conditions.

Langerhans cell histiocytosis with multifocal bone lesions: comparative clinical features between single and multi-systems.

Langerhans cell histiocytosis (LCH) can be a single system or multi-system disease. Both disease types can be associated with multi-focal bone lesions, but their bone involvement patterns have not been compared systematically. Of the new pediatric LCH cases enrolled into the JLSG-02 study during 2002-2007, 67 cases of single system multifocal bone (SMFB) LCH and 97 cases of multi-system bone (MSB) LCH were analyzed to determine if the bone involvement patterns differ in these two types, and whether these differences correlate with outcome. Statistical analysis was performed with Mann-Whitney U test, Fisher's exact test, and other measures. Onset ages were higher for SMFB (P < 0.001), but the two types did not differ in the number of bone lesions per patient. The skull was most frequently affected in both types, followed by the spine. Lesions in the temporal bone (P = 0.002), ear-petrous bone (P < 0.001), orbita (P = 0.003), and zygomatic bone (P = 0.016) were significantly more common in MSB. The two types did not differ in response to treatment, but MSB was associated with a significantly higher incidence of diabetes insipidus (DI) (P < 0.001). Novel measures are required in preventing the development of DI in MSB-type LCH patients with "risk" bone lesions.

Centrosome amplification is correlated with ploidy divergence, but not with MYCN amplification, in neuroblastoma tumors.

Ploidy is an important biologic feature defining heterogeneous neuroblastoma. To clarify whether centrosome amplification is correlated with ploidy status or MYCN amplification, we examined centrosomes by immunostaining, and ploidy and MYCN copy numbers by fluorescence in situ hybridization in 27 neuroblastomas. There were 8 infant triploid, 9 infant diploid, and 10 childhood diploid tumors. Ploidy divergence, defined as a mixed population of cells with trisomy 1, cells with tetrasomy 1, and/or cells with pentasomy 1 in diploid tumors and that of cells with tetrasomy 1 and cells with pentasomy 1 in triploid tumors, each occupying more than 5% of cells, was found in 78% of infant diploid tumors, but not in triploid and childhood diploid tumors (P<0.0001). Childhood and infant diploid tumors had higher incidences of centrosome amplification than infant triploid tumors (P=0.0001 and 0.07, respectively). While both infant and childhood diploid tumors share a high incidence of centrosome amplification, only infant diploid tumors showed ploidy divergence, implying the presence of cytokinesis failure. These findings suggest that centrosome amplification found in cells of infant diploid tumors and that found in cells of childhood diploid tumors may be generated by different mechanisms. MYCN amplification was not correlated with centrosome amplification in sporadic neuroblastomas.

Promoter hypermethylation of the RASSF1A gene predicts the poor outcome of patients with hepatoblastoma.

BACKGROUND: Despite the progress of therapy, about 25% of patients with hepatoblastoma succumb to the disease. Prognostic factors, as well as improved therapies, are needed for these patients. We investigated the incidence and clinical significance of genetic and epigenetic aberrations in hepatoblastoma. PROCEDURE: beta-catenin mutation was analyzed by sequencing and promoter hypermethylation of the RASSF1A and SFRP genes by methylation-specific PCR after bisulfate treatment of DNA samples from 39 hepatoblastomas. Association of the clinical and biological features, including sex, age of patients, stage of the disease, the histological type, and the beta-catenin and RASSF1A status with overall survival was evaluated using univariate and multivariate analysis. RESULTS: beta-catenin mutation and RASSF1A methylation were found in 22 (56.4%) and 15 (38.5%) of 39 hepatoblastomas, respectively, but SFRPs methylation was not found in any of them. RASSF1A and SFRPs were unmethylated in five adjacent normal liver tissues. Patients with a RASSF1A methylated tumor were older in age (>or=2 years, P=0.036), at more advanced stages (P=0.009), and had more frequent beta-catenin mutation (P<0.001) and poorer outcome (P<0.001) than those with a RASSF1A unmethylated tumor. While univariate analysis showed the prognostic significance of age, stage, the histological type, and the beta-catenin and RASSF1A status, multivariate analysis showed only the RASSF1A methylation status as an independent factor predicting outcome (relative risk, 10.51; 95% CI, 1.21 approximately 90.97; P=0.033). CONCLUSIONS: RASSF1A methylation may be a novel molecular-genetic marker for treatment outcome in hepatoblastoma if confirmed by studies examining a larger number of hepatoblastomas.

Improved outcome in the treatment of pediatric multifocal Langerhans cell histiocytosis: Results from the Japan Langerhans Cell Histiocytosis Study Group-96 protocol study.

BACKGROUND: The treatment outcome of multifocal childhood Langerhans cell histiocytosis (LCH) has not been satisfactory and has resulted in poor therapeutic responses with high mortality and a high incidence of reactivation with late sequelae. To overcome these issues, the Japan LCH Study Group-96 (JLSG-96) protocol was conducted prospectively from 1996 to 2001 in Japan. METHODS: Newly diagnosed children with multifocal LCH were classified into 2 groups: a single-system multisite (SS-m) group and a multisystem (MS) group. All patients initially were treated on Protocol A, which consisted of 6 weeks of induction therapy with combined cytosine arabinoside, vincristine (VCR), and prednisolone (PSL) followed by 6 months of maintenance therapy. Patients who had a poor response to the induction of Protocol A were switched to a salvage regimen (Protocol B), which consisted of an intensive combination of doxorubicin, cyclophosphamide, VCR, and PSL. RESULTS: In total, 91 patients were treated, including 32 patients in the SS-m group and 59 patients in the MS group. At the median 5-year follow-up, 96.9% of patients in the SS-m group and 78.0% of patients in the MS group had good response status. Diabetes insipidus developed in 3.1% of patients in the SS-m group and in 8.9% of patients in the MS group. The overall survival rate at 5 years for the SS-m and MS groups was 100% and 94.4% +/- 3.2%, respectively. CONCLUSIONS: The JLSG-96 protocol attained very low mortality for pediatric patients with multifocal LCH.