Dedifferentiated liposarcoma in the extremity and trunk wall: A multi-institutional study of 132 cases by the Japanese Musculoskeletal Oncology Group (JMOG).

BACKGROUND: Dedifferentiated liposarcoma occurs predominantly in the retroperitoneum. Given the paucity of cases, information on the clinical characteristics of this entity in the extremities and trunk wall is quite limited. In particular, the significance of preoperative evaluation and principles of intraoperative management of the different components, i.e., well-differentiated and dedifferentiated areas, are still to be defined. METHODS: Clinical characteristics, treatment outcomes, and risk factors for poor oncological outcomes in cases of dedifferentiated liposarcoma in the extremity or trunk wall were analyzed by a retrospective, multicentric study. RESULTS: A total of 132 patients were included. The mean duration from the initial presentation to dedifferentiation was 101 months in dedifferentiation-type cases. The 5-year local recurrence-free survival, metastasis-free survival, and disease-specific survival rates were 71.6%, 75.7%, and 84.7%, respectively. Among 32 patients with metastasis, 15 presented with extrapulmonary metastasis. A percentage of dedifferentiated area over 87.5%, marginal/intralesional margin, and R1/2 resection in the dedifferentiated area were independent risk factors for local recurrence. Dedifferentiated areas over 36 cm2, French Federation of Cancer Centers Sarcoma Group grade III, and intralesional or marginal resection were independent risk factors for metastasis. A dedifferentiated area over 77 cm2 and lung metastasis were independent risk factors for disease-specific mortality. CONCLUSIONS: The typical clinical characteristics of dedifferentiated liposarcoma in the extremity and trunk wall were reconfirmed in the largest cohort ever. The evaluation of the dedifferentiated area in terms of grade, extension, and pathological margin, together with securing adequate surgical margins, was critical in the management of this entity.

Impact of comorbidities on oncological outcomes of Japanese patients with high grade soft tissue sarcomas.

BACKGROUND: Considering the invasiveness of standard multidisciplinary approaches used for the treatment of soft tissue sarcoma, including surgery with wide margins, intensive chemotherapy, and radiotherapy, evaluation of comorbidities in high-grade soft tissue sarcoma patients is essential. Several previous studies have reported the impact of comorbidities on the survival of soft tissue sarcoma patients. Patient health status differs between nationalities or ethnic groups and only limited data has been reported with respect to the impact of comorbidities on Japanese soft tissue sarcoma patients. METHODS: The incidence of each comorbidity, relationship between comorbidities and underlying clinicopathological factors, relationship between treatment status and comorbidities, and impact of comorbidities on disease-specific death in 136 patients with high-grade soft tissue sarcoma at the authors' institution were analyzed. For the evaluation of comorbidities, the updated Charlson comorbidity index was applied. RESULTS: Of the patients, 25% presented with more than one comorbidity. Elderly patients showed a significantly higher incidence of comorbidities (p < 0.0001). Patients with congestive heart failure (p = 0.004), dementia (p < 0.0001), hemiplegia/paraplegia (p < 0.0001), and renal disease (p < 0.0001) showed worse prognosis. Tumor grade (p = 0.01) and updated Charlson comorbidity index (p < 0.0001) were independent risk factors for disease-specific death. CONCLUSIONS: Comorbidity status was a significant risk factor for disease-specific death in Japanese patients with high-grade soft tissue sarcoma. Innovations in comorbidity management may be a means for the improvement of oncological outcomes in soft tissue sarcoma. Given the difficulties in conducting standard randomized control studies in this field, data accumulation from real-world cases appears to be the most practical approach in establishing and applying strategies for the treatment of patients with comorbidities or elderly patients.

Langerhans Cell Histiocytosis of the Clavicle in an Adult: A Case Report and Review of the Literature.

Langerhans cell histiocytosis (LCH) usually occurs in children under the age of 10 years with a predilection for the skull, spine, rib and humerus. Solitary LCH occurring in an adult clavicle is uncommon with limited reports to date. The lesion in our patient was curetted with the intent to make a diagnosis, which subsequently lead to the remission of the symptom and the disease. At the final follow-up after 1 year, no local recurrence or metastasis is observed.

Multiplex PCR/liquid chromatography assay for screening of subtelomeric rearrangements.

In idiopathic or nonspecific mental retardation, the overall rate of cryptic subtelomeric rearrangements is estimated to be about 5%. Development of cost-effective screening for subtelomeric deletions would help clinical geneticists to make specific diagnoses in children with idiopathic mental retardation. Current screening modalities include fluorescence in situ hybridization (FISH) using subtelomeric probes and PCR-based quantitative analyses. Reductions in the cost and turnaround time will make the complete screening of subtelomeric rearrangements more widely used in clinical settings. Recently, a versatile method, called the multiplex PCR/liquid chromatography assay (MP/LC), was developed to assess copy numbers in this assay. Multiple genomic regions are amplified using unlabeled primers, then separated by ion-pair reversed-phase high-performance liquid chromatography. In the present study, we developed an MP/LC-based subtelomeric screening system that involves 21 multiple reactions and validated the protocol by analyzing 16 publicly available cell lines with known cytogenetic abnormalities involving at least one subtelomere per patient. To confirm the validity of the MP/LC method, we analyzed these cell lines concurrently with array-based comparative genomic hybridization (array-CGH), which gives higher resolution than the conventional G-banding technique. Among those 16 samples, the results from MP/LC and array-CGH agreed with each other perfectly. In 2 of the 16 samples, MP/LC correctly revealed subtelomeric duplications that were detected by array-CGH but were undetected by conventional cytogenetics, demonstrating the sensitivity of the MP/LC assay. This system is expected to be useful for making specific diagnoses and in genetic counseling for children with idiopathic mental retardation, a sizable fraction of whom have subtelomeric rearrangements.

Identification of a prosencephalic-specific enhancer of SALL1: comparative genomic approach using the chick embryo.

Comparative genomics is a promising approach for identifying regulatory elements governing the unique spatio-temporal expression patterns of morphogenetic genes. Conserved noncoding genomic sequences are candidate regulatory elements. Here we performed a survey for conserved noncoding elements (CNE) nested within the SALL1 gene; mutations in this gene result in the Townes-Brocks syndrome. A comparison of the genomic sequence between humans and chicken revealed five CNE. Genomic fragments corresponding to each CNE were inserted into reporter cassettes consisting of eGFP cDNA and a minimal promoter. These constructs were electroporated into chick embryos during gastrula, neurula, and pharyngula stages. Among the five CNE that were examined, one 443 bp CNE exhibited tissue-specific enhancer activity. At the neurula stage, the eGFP signal was visualized in the prosencephalon. At the pharyngula stage, the eGFP signal was confined within the anterior neural ridge, which represents one of the morphogenetic centers regulating the patterning of the anterior neural plate. This report identifies, for the first time, an enhancer element of SALL1.

An Alu retrotransposition-mediated deletion of CHD7 in a patient with CHARGE syndrome.

CHD7 mutations account for about 60-65% among more than 200 CHARGE syndrome cases. When rare whole gene deletion cases associated with chromosomal abnormalities are excluded, all mutations of CHD7 reported to date have been point mutations and small deletions and insertions, rather than exonic deletions. To test whether exonic deletions represent a common pathogenic mechanism, we assessed exon copy number by using a recently developed method, the multiplex PCR/liquid chromatography assay (MP/LC). Multiple exons were amplified using unlabeled primers, then separated by ion-pair reversed-phase high-performance liquid chromatography, and quantitated by fluorescence detection using a post-column intercalation dye under the premise that the relative peak intensities for each target directly reflect exon copy number. By using MP/LC, we identified one CHARGE syndrome patient who had a de novo deletion encompassing exons 8-12 among 13 classic CHARGE patients in whom screening by denaturing high-performance liquid chromatography (DHPLC) failed to identify point mutations and small insertions/deletions in CHD7. This is the first CHARGE patient who was documented to have exonic deletion of CHD7. The deletion closely recapitulated the Alu-mediated inactivation of the human CMP-N-acetylneuraminic acid hydroxylase gene (CMP-Neu5Ac hydroxylase), which is regarded as a novel molecular mechanism in the evolution from non-human primates to humans. As demonstrated in this study, MP/LC is a promising method for characterizing exonic deletions, which are largely left unexamined in most routine mutation analysis.

Embryonic expression profile of chicken CHD7, the ortholog of the causative gene for CHARGE syndrome.

BACKGROUND: CHARGE syndrome represents a constellation of malformations: C, coloboma of the iris or retina; H, heart defects; A, atresia of the choanae; R, retardation of growth and/or development; G, genital anomalies; and E, ear abnormalities. Recently, the Chromodomain helicase DNA-binding protein-7 (CHD7) at chromosome 8q12.1 was identified as a causative gene for CHARGE syndrome. Because CHD7 was identified as a causative gene using a positional cloning approach, the role of CHD7 in early embryogenesis needs to be further investigated. METHODS: Fertilized chick eggs were incubated to Hamburger and Hamilton stages 4-20 and were studied using whole mount in situ hybridization. Chicken EST clones corresponding to the chicken CHD7 (cChd7) sequence were identified using the chicken EST sequence database. From the EST clones, a digoxigenin-labeled RNA probe was synthesized and hybridized in situ to the embryonic specimens. RESULTS: The expression of cChd7 was pan-neuronal at stages 8-20. It was expressed throughout the rostral neural ectoderm and along the rostrocaudal axis but was absent from the more lateral, non-neuronal ectoderm. Adjacent to the neural tube, cChd7 transcripts were detected at the optic and otic placodes. At stage 20, cChd7 expression was observed in the branchial arches and olfactory placodes in addition to brain and optic and otic placodes. CONCLUSIONS: cChd7 was expressed in the neural epithelium, the otic placodes, the optic placodes, the branchial arches, and the olfactory placodes, which are the primordial tissues that give rise to organs affected in human CHARGE syndrome patients.

Kallmann syndrome phenotype in a female patient with CHARGE syndrome and CHD7 mutation.

We report on a 14 7/12-year-old Japanese female patient with CHARGE syndrome and CHD7 mutation who also exhibited Kallmann syndrome (KS) phenotype. She had poor pubertal development and apparently impaired sense of smell. A GnRH test showed severely compromised responses of LH (<0.5 --> <0.5 IU/L) and FSH (<0.5 --> 1.2 IU/L), and magnetic resonance imaging delineated hypoplastic olfactory bulbs. Mutation analysis revealed a heterozygous nonsense mutation at exon 33 of CHD7 (7027C>T, Q2343X). The results provide further support for the notion that KS phenotype can be included in the phenotypic spectrum of CHARGE syndrome, and indicate that CHARGE syndrome with KS phenotype is caused by a CHD7 mutation.

Paternal gonadal mosaicism of NIPBL mutation in a father of siblings with Cornelia de Lange syndrome.

OBJECTIVES: We report two siblings, a boy and a girl, with Cornelia de Lange syndrome (CdLS), born to unaffected parents, and attempt to delineate the underlying molecular mechanism leading to familial recurrence. METHODS: Nipped-B-like (NIPBL) gene mutations were screened using in denaturing high-performance liquid chromatography and sequencing in peripheral blood samples, from one of the affected siblings and her parents, as well as from a sperm sample from the father. RESULTS: A heterozygous missense NIPBL mutation, D2433G, was identified in the peripheral blood sample of the affected girl, but not in the peripheral blood samples of her parents. The D2433G mutation was also found in the sperm sample of the father. CONCLUSION: Gonadal mosaicism represents an underappreciated feature of the inheritance pattern of CdLS. To our knowledge, the girl represents the first CdLS patient whose father was documented to have a population of mutant sperm. When a sperm analysis indicates the presence of a mutant allele, it may be reasonable to offer prenatal genetic testing to the family in subsequent pregnancies, given that the sensitivity of fetal ultrasonography is relatively low.

Phenotypic spectrum of CHARGE syndrome with CHD7 mutations.

CHD7 gene mutations were identified in 17 (71%) of 24 children clinically diagnosed to have CHARGE syndrome (C, coloboma of the iris or retina; H, heart defects; A, atresia of the choanae; R, retardation of growth and/or development; G, genital anomalies; and E, ear abnormalities). Colobomata, hearing loss, laryngomalacia, and vestibulo-cochlear defect were prevalent. Molecular testing for CHD7 enables an accurate diagnosis and provides health anticipatory guidance and genetic counseling to families with CHARGE syndrome.

Screening for CHARGE syndrome mutations in the CHD7 gene using denaturing high-performance liquid chromatography.

Mutations in the CHD7 (chromodomain helicase DNA binding protein 7) gene cause CHARGE syndrome. At present, however, genetic testing of the CHD7 gene is not commonly applied in clinical settings because the currently available assays are technically and financially demanding, mainly because of the size of the gene. In the present study, we optimized the highly sensitive and specific mutation scanning method automated denaturing high-performance liquid chromatography (DHPLC) to analyze the entire coding region of CHD7. The coding region was amplified by 39 primer pairs, all of which have the same cycling conditions, aliquoted on a 96-well format polymerase chain reaction (PCR) plate. In this manner, all of the exons were amplified simultaneously using a single block in a thermal cycler. We then wrote a computer script to analyze each segment of the CHD7 gene by DHPLC in a serial manner using conditions that were optimized for each amplicon. The implementation of this screening method for CHD7 will help medical geneticists confirm their clinical impressions and provide accurate genetic counseling to the patients with CHARGE syndrome and their families.

Screening for partial deletions in the CREBBP gene in Rubinstein-Taybi syndrome patients using multiplex PCR/liquid chromatography.

Rubinstein-Taybi syndrome (RTS, MIM 180849) is a multiple malformation syndrome characterized by growth retardation, developmental delay, and dysmorphic features, including down-slanting palpebral fissures, a beaked nose, broad thumbs, and halluces. Mutations in the gene encoding the CREB-binding protein gene (CREBBP, also known as CBP) on chromosome 16p13.3 were identified in 1995. Recently, we developed a mutation analysis protocol using denaturing high-performance liquid chromatography (DHPLC) and identified heterozygous CREBBP mutations in 12 of 21 RTS patients. To test whether exonic deletions represent a common pathogenic mechanism, we assessed the copy number of all the coding exons using a recently developed method, the multiplex PCR/liquid chromatography assay (MP/LC). By using MP/LC, we performed screening for CREBBP exonic deletions among 25 RTS patients in whom no point mutations or small insertions/deletions were identified by DHPLC screening. We identified four classic RTS patients with deletions encompassing multiple exons (14-16, 5-31, 1-16, and 4-26). We conclude that large deletions including several exons are a relatively frequent cause of RTS, and that MP/LC is an effective method for detecting these deletions.

Comprehensive screening of CREB-binding protein gene mutations among patients with Rubinstein-Taybi syndrome using denaturing high-performance liquid chromatography.

Mutations in the CREBBP (CREB-binding protein gene) cause Rubinstein-Taybi syndrome (RSTS). At present, however, genetic testing of CREBBP is not commonly applied in clinical settings because the currently available assays are technically and financially demanding, mainly because of the size of the gene. In the present study, we took advantage of a highly sensitive and specific, automated denaturing high-performance liquid chromatography (DHPLC) technique. First, we developed a DHPLC-based protocol to analyze the entire coding region of CREBBP. Second, we analyzed genetic samples from 21 RSTS patients using DHPLC. The coding region was amplified by 41 primer pairs, all of which have the same cycling conditions, aliquoted on a 96-well format PCR plate. In this manner, all the exons were simultaneously amplified using a single block in a PCR machine. We then wrote a computer script to analyze all the PCR amplicons generated from various portions of the CREBBP gene in a serial manner at optimized conditions determined individually for each amplicon. Heterozygous CREBBP mutations were identified in 12 of the 21 patients: five frameshift mutations, three nonsense mutations, two splice-site mutations, and two missense mutations. The resulting detection rate of 57% was comparable to the outcome of previous studies. The relatively high detection rate in the present study demonstrates the enhanced sensitivity of the DHPLC-based mutation analysis, as exemplified by mutation analyses of other genes. The implementation of similar methodologies for other dysmorphic syndromes will help medical geneticists to confirm their clinical impressions and to provide accurate genetic counseling for patients and their families.

DHPLC in clinical molecular diagnostic services.

A high-capacity low-cost mutation scanning method based on denaturing high-performance liquid chromatography (DHPLC) has been recently introduced. We have implemented an automated and cost-effective strategy using DHPLC. To facilitate the semi-automated analysis of multiple exons, two steps were taken. The first step was the development of a PCR protocol for the amplification of multiple exons under the same conditions. Primer sets, which amplify each exon in the entire gene, were aliquoted to and air-dried on a 96-well format PCR plate. In this way, all the exons in a gene can be simultaneously amplified on a single PCR machine. The second step was the serial DHPLC analysis of multiple amplicons under conditions optimal for each amplicon. We named the 96-well plate containing the primer pairs and the corresponding computer file used to analyze each amplicon under the pre-determined optimal conditions as the "Condition-Oriented-PCR primer-Embedded-Reactor plate," or the COPPER plate. We have developed COPPER plate systems for more than 20 congenital disorders including classic congenital syndromes like Marfan syndrome (FBN1: 65 amplicons), CHARGE syndrome (CHD7: 39 amplicons), de Lange syndrome (NIPBL: 46 amplicons), Sotos syndrome (NSD1: 30 amplicons), and Rubinstein-Taybi syndrome (CREBBP: 41 amplicons). Using the COPPER plate system, we are functioning as a reference laboratory for the clinical molecular diagnosis of congenital malformation syndromes and are presently analyzing more than 200 samples annually from all over Japan.

Comprehensive screening of the thiopurine methyltransferase polymorphisms by denaturing high-performance liquid chromatography.

The drug-metabolizing enzyme thiopurine S-methyltransferase (TPMT) catalyzes the S-methylation of thiopurines such as 6-mercaptopurine, 6-thioguanine, and azathiopurine, which are used as immunosuppressants and in the treatment of acute lymphoblastic leukemia and rheumatoid arthritis. TPMT enzymatic activity is a polymorphic trait, and poor metabolizers may develop life-threatening bone marrow failure. To avoid such adverse effects, the TPMT enzymatic activity in patients' red blood cells (RBCs) is routinely measured prior to thiopurine administration in a limited number of oncology clinics. In the present study, we took advantage of a highly sensitive and specific automated denaturing high-performance liquid chromatography (dHPLC) technique that not only detects known polymorphic alleles, but also identifies previously uncharacterized sequence variants. We developed a dHPLC-based protocol to analyze the entire coding region and validated the protocol to detect all 16 previously described variant alleles. We further analyzed the entire coding region of the TPMT gene in 288 control samples collected worldwide and identified two novel amino acid substitutions Arg163Cys (487C>T) and Arg226Gln (677G>A) within exons 7 and 10, respectively. The clinical application of this comprehensive screening system for examining the entire TPMT gene would help to identify patients at risk for bone marrow failure prior to 6-mercaptopurine therapy.