PubMed Health⌕ Search

Biomedical subjects

H Rieder

Publications and source records attributed to H Rieder.

At least 19 recordsLinked to original sources
PubMed2005

Anticipation in familial pancreatic cancer.

BACKGROUND: Previous studies of anticipation in familial pancreatic cancer have been small and subject to ascertainment bias. Our aim was to determine evidence for anticipation in a large number of European families. PATIENTS AND METHODS: A total of 1223 individuals at risk from 106 families (264 affected individuals) were investigated. Generation G3 was defined as the latest generation that included any individual aged over 39 years; preceding generations were then defined as G2 and G1. RESULTS: With 80 affected child-parent pairs, the children died a median (interquartile range) of 10 (7, 14) years earlier. The median (interquartile range) age of death from pancreatic cancer was 70 (59, 77), 64 (57, 69), and 49 (44, 56) years for G1, G2, and G3, respectively. These indications of anticipation could be the result of bias. Truncation of Kaplan-Meier analysis to a 60 year period to correct for follow up time bias and a matched test statistic indicated significant anticipation (p=0.002 and p<0.001). To minimise bias further, an iterative analysis to predict cancer numbers was developed. No single risk category could be applied that accurately predicted cancer cases in every generation. Using three risk categories (low with no pancreatic cancer in earlier generations, high with a single earlier generation, and very high where two preceding generations were affected), incidence was estimated without significant error. Anticipation was independent of smoking. CONCLUSION: This study provides the first strong evidence for anticipation in familial pancreatic cancer and must be considered in genetic counselling and the commencement of secondary screening for pancreatic cancer.

Adult↗
PubMed2005

Molecular heterogeneity of sporadic adult Burkitt-type leukemia/lymphoma as revealed by PCR and cytogenetics: correlation with morphology, immunology and clinical features.

Chromosomal translocations involving the MYC oncogene are a hallmark of Burkitt lymphoma but they are only found in a varying frequency in mature Burkitt-type acute lymphoblastic leukemia (B-ALL). We have investigated samples of 56 sporadic Burkitt leukemia/lymphoma patients for the translocations t(8;14)(q24;q32), t(2;8)(p11;q24) and t(8;22)(q24;q11). Long PCR was used for detecting the immunoglobulin heavy chain (IgH) translocation and cytogenetics and/or fluorescence in situ hybridization for detecting the 'variant' MYC translocations. A total of 29 samples (51.8%) were t(8;14)-positive by long PCR. Approximately one-third had a chromosomal breakpoint in the IgH joining region while the others had breakpoints in the IgH switch regions. Among them were two cases with a previously unreported MYC translocation into the IgE switch region. Long PCR was more reliable compared to conventional cytogenetics for detecting the t(8;14). Epstein-Barr virus was detected in high copy number in two (3.6%) t(8;14)-positive cases by real-time quantitative PCR. Human herpesvirus 8 was not detected in any case by nested PCR. A typical L3 or L3-compatible cytomorphology was highly predictive (>80%) but not specific of a MYC translocation. A total of 34 patients were treated according to the GMALL B-ALL therapy protocols and there was no significant difference in overall survival between patients with or without t(8;14).

Adolescent↗
PubMed2005

Annual risk of infection with Mycobacterium tuberculosis.

The average annual risk of infection with Mycobacterium tuberculosis is a calculated average from an observed prevalence of infection, approximating the incidence of infection. It has the potential to be informative about the extent of transmission in a community. Where serial surveys are available, secular trends in transmission might be ascertained. The prerequisite for calculating the average annual risk is the successful determination of the prevalence of infection. Difficulties arising with tuberculin skin-test surveys include logistical problems in sampling a representative portion of the population. Therefore, a compromise assesses the prevalence of infection among school children as an indicator of transmission in the community at large. The utilisation of tuberculin surveys is further compounded by the unpredictable specificity of the tuberculin skin test and, thus, the predictive value of a positive test result. Statistical approaches using mixture analysis may overcome this problem to some extent, but the experience is limited. Cytokine-derived assays, such as the interferon-gamma release assays, are promising in providing higher specificity, but they require venepuncture.

Adolescent↗
PubMed2003

German multicenter study group for adult ALL (GMALL): recruitment in comparison to ALL incidence and its impact on study results.

Due to eligibility criteria not all patients with the disease under investigation can be recruited for therapeutic studies. Thus, the external validity of study results cannot per se be taken for granted. The representativity of the admitted patients is the most relevant determinant for external validity and has to be assessed. As an example we examined the representativity of the patients recruited for the German multicenter study group for adult acute lymphoblastic leukemia (ALL) (GMALL). Lacking nationwide ALL incidence figures available in Germany, a methodology was developed to estimate incidence figures, too. All relevant study groups, hospitals, and diagnostic labs were asked to provide data about patients with ALL newly diagnosed between 1997 and 1998. A matching procedure was developed, as heterogeneous databases had to be pooled and checked for duplicates. Age- and sex-specific incidences of ALL were estimated and compared with the number of patients recruited for the GMALL in the same time period. The purpose was to develop a methodology for estimating incidence figures and evaluating the representativity of patients of the GMALL. The combination of various data sources allowed estimation of reliable incidence data for ALL in Germany. Comparisons with the incidence figures for ALL in other countries and crosschecks within Germany confirm our results. Sixty-two percent of all ALL patients in Germany were admitted to the GMALL study. The recruitment rate of more than 60% of the annual incidence of ALL to the GMALL suggests a high external validity as well as an impact of the study on the patterns of treatment and referral of ALL in adults in Germany. There is no selection bias of patients admitted to the GMALL compared to those patients not included in the study.

Adolescent↗
PubMed2003

Expression of the human homologue of rat NG2 in adult acute lymphoblastic leukemia: close association with MLL rearrangement and a CD10(-)/CD24(-)/CD65s(+)/CD15(+) B-cell phenotype.

The expression of the chondroitin sulfate proteoglycan neuron-glial antigen 2 (NG2) has been demonstrated in association with rearrangement of the mixed lineage leukemia (MLL) gene in acute leukemia, but the frequency of NG2 expression in adult acute lymphoblastic leukemia (ALL) is yet unknown. We evaluated NG2 expression in 313 adult ALL patients by flow cytometry and simultaneously determined MLL rearrangement in 120 adult patients out of them with B-precursor ALL by reverse transcription-polymerase chain reaction and fluorescence in situ hybridization. A total of 57% of pro-B ALL, 2% of common ALL and 20% of pre-B ALL were NG2 positive, but NG2 was absent in T-ALL and mature B-ALL. In B-precursor ALL, NG2 expression was significantly associated with a CD10(-)/CD34(-)/CD24(-)/CD65s(+)/CD15(+)/CD13(-)/CD33(-) phenotype and showed a sensitivity, specificity and positive predictive value of 0.89, 0.89, and 0.93 for MLL rearrangement, respectively. NG2 was positive in three patients without detectable MLL rearrangement and negative in eight patients with MLL-AF4 transcripts. However, NG2 predicted with a 100% accuracy MLL rearrangement among patients disclosing a CD65s(+) and/or CD15(+) immunophenotype. In summary, NG2 adds to a more precise identification of high-risk adult ALL and should therefore be included into diagnostic marker panels. As NG2 is negative in non-malignant hematopoietic cells, this novel antigen might also serve in future studies as a powerful marker in monitoring minimal residual disease.

Adolescent↗
PubMed2002

German national case collection of familial pancreatic cancer - clinical-genetic analysis of the first 21 families.

BACKGROUND: The observation of a familial accumulation of ductal pancreatic adenocarcinoma (PC) and the increased risk for PC in certain hereditary tumor syndromes point to a genetic predisposition for PC. In order to evaluate the characteristics of familial PC, a German national case collection for familial pancreas cancer (FaPaCa) was established. PATIENTS AND METHODS: In FaPaCa, families of patients with PC are being collected, who have at least 1 first-degree relative with PC or with malignant melanoma. Histopathologic verification of tumor diagnoses, acquisition of clinical data, and full genetic counselling are prerequisites for the enrollment of PC families in FaPaCa. RESULTS: So far, 21 families fulfilled the criteria for partaking in FaPaCa. In 11 families, PC represented the sole tumor entity. Additional tumors included malignant melanoma in 5, breast cancer in 3, and prostatic, colon or lung cancer in 2 families. Compared to the preceding generation, a younger age at diagnosis of PC was observed in the offspring of PC patients (offspring median 53 years vs. parents median 75.5 years). CONCLUSION: The association of PC and breast cancer, and of PC and malignant melanoma suggests predisposing mutations in the BRCA2 or CDKN2A genes in about one third of the FaPaCa families. Mutational analyses in both candidate genes may help to identify individuals who are at an increased risk for developing PC. A shift towards a younger age at diagnosis in our PC families may indicate genetic anticipation and/or changes of patterns of exogenous risk factors.

Adult↗
PubMed2001

Partial deletions of the long and short arm of chromosome 3 point to two tumor suppressor genes in uveal melanoma.

Uveal melanoma is the most common form of primary eye cancer. Monosomy 3, which is an unusual finding in tumors but is present in approximately 50% of uveal melanomas, is significantly correlated with metastatic disease. To obtain positional information on putative tumor suppressor genes on this chromosome, we have investigated tumors from 333 patients by comparative genomic hybridization, microsatellite analysis, or conventional karyotype analysis. A partial deletion of the long arm was found in eight tumors, and the smallest region of deletion overlap (SRO) spans 3q24-q26. We found six tumors with a partial deletion of the short arm and were able to define a second SRO of about 2.5 Mb in 3p25. This SRO does not overlap with the VHL gene. Our finding suggests a role for two tumor suppressor genes in metastasizing uveal melanoma and may explain the loss of an entire chromosome 3 in these tumors.

Chromosome Deletion↗
PubMed2001

Interphase fluorescence in situ hybridization assay for the detection of 3q21 rearrangements in myeloid malignancies.

In myeloid malignancies, chromosome rearrangements involving band 3q21 are associated with a particularly poor prognosis of the disease. Their sensitive and unequivocal detection is therefore of great clinical importance. In this report, we describe the establishment of an interphase fluorescence in situ hybridization (FISH) assay that complements classical cytogenetic analysis in the diagnosis of such aberrations. PACs that map centromeric and telomeric of known 3q21 breakpoints were labeled with different fluorescent dyes, and the separation of the normally colocalizing signals was used as an indicator of the presence of a 3q21 rearrangement. Two cell lines and 10 primary samples from myeloid leukemia and myelodysplastic syndrome (MDS) patients with 3q21 rearrangements were investigated using the newly established method. The rate of false positivity was determined in 27 control samples from patients with various types of myeloid malignancies. In addition to providing a sensitive and rapid test for the detection of 3q21 aberrations, the interphase FISH assay yields preliminary information about the localization of individual breakpoints. Six of the 10 breakpoints in the patient samples map to an only recently described breakpoint cluster region (BCR) 60 kb centromeric of the originally reported 3q21 BCR. These findings may contribute to the understanding of the molecular basis of the clinical features associated with 3q21 rearrangements.

Adult↗
PubMed2001

Predictive genetic screening and clinical findings in multiple endocrine neoplasia type I families.

Germline mutations of the MEN1 gene have been identified as the causative genetic defect of multiple endocrine neoplasia type I (MEN-I), an autosomal dominantly inherited condition. To establish the basis for predictive family screening we evaluated the spectrum of MEN1 gene mutations in MEN-I patients treated at our institution. Relatives at risk were subjected to predictive genetic screening after genetic counseling. Gene carriers were subjected to extensive clinical screening for MEN-I, including biochemical tests for basal hormone concentrations in blood and urine, a standardized meal stimulation test and imaging procedures (ultrasonography, computed tomography, magnetic resonance imaging). Among index patients of 15 independent MEN-I kindreds, 14 heterozygous MEN1 germline mutations were identified by single-strand conformational variant analysis (SSCV) and direct DNA sequence analysis. Of 51 individuals at risk, 26 predictively tested relatives with the wild-type MEN1 gene could be excluded from further screening procedures because they had not inherited the disease. In all previously presumed unaffected relatives with the mutant gene, our extensive clinical screening program revealed at least one manifestation of MEN-I. Furthermore, 22 additional diagnoses could be established in identified MEN-I patients. We show that mutation analysis enables predictive genetic screening for MEN-I families, providing a valuable tool for genetic counseling and clinical management. An extensive clinical screening program focusing on genetically proven individuals at risk allows detection of MEN-I manifestations at an early, asymptomatic stage of the disease. Controlled, prospective studies are now required to prove whether timely appropriate treatment on the basis of predictive screening might help improve disease-related quality of life and prolong life expectancy in MEN-I kindreds.

DNA Mutational Analysis↗
PubMed2001

Marked differences in unilateral isolated retinoblastomas from young and older children studied by comparative genomic hybridization.

Although it is established that the loss of function of both alleles of the RB1 gene is a prerequisite for the development of retinoblastoma, little is known about the genetic events that are required for tumor progression. We used comparative genomic hybridization (CGH) to search for DNA copy number changes in isolated unilateral retinoblastomas. From a series of 66 patients with retinoblastomas with somatic mutations in both RB1 alleles, tumor samples from 13 children with the youngest (2.0-9.8 months) and 13 with the oldest (36.2-84.1 months) age at operation were studied. Loss at 13q14, the location of RB1, was demonstrated in two tumors only. Recurring chromosome imbalances included gains at 6p (11/26), 1q (10/26), 2p (4/26), and 17q (4/26), gains of the entire chromosome 19 (3/26), and losses at 16q (9/26). A commonly gained region at 1q32 was identified. Increased dosage of GAC1, a candidate oncogene located in 1q32, was found in two of four tumors by Southern blot analysis. Comparison of the CGH findings revealed that retinoblastomas from children with an older age at operation showed significantly more frequent (13/13 cases vs 4/13 cases; P = 0.0005) and more complex genetic abnormalities (median, 5 changes/abnormal tumor vs median, 1.5 changes/abnormal tumor; P = 0.003) than retinoblastomas from children with a young age at operation. Gains at 1q, 2p, 17q, of the entire chromosome 19 and losses of 16q were restricted to the older age group. Our results suggest that the progression of retinoblastomas from older patients follows mutational pathways different from those of younger patients.

Blotting, Southern↗
PubMed2001

Prospective BCR-ABL analysis by polymerase chain reaction (RT-PCR) in adult acute B-lineage lymphoblastic leukemia: reliability of RT-nested-PCR and comparison to cytogenetic data.

The reliability of routine BCR-ABL RT-nested-PCR was evaluated in 1453 B-lineage ALL or hybrid leukemia at initial diagnosis by RT-nested-PCR. All BCR-ABL-positive (n = 642) and 176 BCR-ABL-negative samples underwent a second RT-PCR. In 518 patients, karyotyping and/or FISH was compared to the BCR-ABL status. The second RT-PCR revealed in 155/642 initially positive samples a divergent result (153 BCR-ABL-negative, two other transcripts) that in most cases turned out to be caused by contaminations in the first RT-nested-PCR. Confirmatory RT-PCR detected 2/176 false negative first RT-nested-PCR results. Thirty-nine specimens remained ambiguous despite different RT-PCR approaches. As far as cytogenetic evaluation and FISH is available (n = 23), the majority but not all patients with an ambiguous RT-PCR result were Ph-negative (n = 18). RT-nested-PCR and cytogenetics yielded in 346 of 383 evaluable samples a concordant result. Differing results are given and account in part to the lower sensitivity of karyotyping. Taken together, confirmed RT-PCR detected BCR-ABL fusion transcripts consistently in 487 out of 1453 ALL samples (c-ALL: 43%, pre-B ALL: 34%, pro-B ALL: 5%, B-ALL: 0%, hybrid leukemia: 5/11). Since false positive initial RT-nested-PCR data were frequent, either confirmatory second RT-PCR or FISH analysis is warranted to guarantee sensitive and reliable results of utmost clinical relevance.

Adult↗
PubMed2001

Update of familial pancreatic cancer in Germany.

BACKGROUND/AIMS: The prevalence of familial pancreatic cancer (FPC) and the characteristics of FPC have not yet been well investigated in the German population. Therefore, a German case collection for FPC was established in July 1999 to collect and evaluate data on FPC families. METHODS: The prevalence of pancreatic cancer (PC) as well as other tumours and diseases was studied in families with at least 2 first-degree relatives with histologically confirmed PC, and in families of patients with PC and a first-degree relative with malignant melanoma. All participating family members were genetically counselled and evaluated by a standardised questionnaire. RESULTS: In an 18-month period, 73 independent kindreds with potential FPC contacted the national case collection. So far, 20 kindreds have fulfilled the criteria for FPC and have undergone complete workups. Most families revealed an autosomal dominant pattern of inheritance. Twelve families revealed an isolated accumulation of PC. Importantly, in 8 of 20 (35%) families, additional tumour types such as melanoma, breast and prostate cancer occurred. CONCLUSION: The observed phenotypic heterogeneity indicates an association with predisposing tumour suppressor genes p16 and BRCA2 in up to 30% of FPC families. Mutation analysis of these candidate genes might lead to the identification of the predisposing gene defect in a proportion of FPC families.

Genetic Counseling↗
PubMed2001

MDR-1 expression and deletions of chromosomes 7 and 5(Q) separately indicate adverse prognosis in AML.

In order to assess any correlation between MDR-1 expression and chromosomal aberrations, and to define their impact on clinical outcome in newly diagnosed AML pts, we investigated bone marrow and peripheral blood samples of 49 consecutive pts admitted to our hospital. Monosomy 7, trisomy 8 and 5q- were evaluated by means of interphase fluorescence in situ hybridization (FISH). Monosomy 7 was present in 6 pts, trisomy 8 in 5 pts, and 5q- in 6 pts. More than one aberration was seen in 7 pts. Chromosomal aberrations were mostly found in older pts (12/14 >60 years; p=0.03) and in pts with CD34 positive leukemic blasts (13/14 coexpressed CD34, p=0.0004). In 25 pts also standard G-banding analysis was performed leading to concordant results regarding chromosomes 7, 8 and 5. Flow cytometry identifyed MDR-1 positivity (MDR+) in 16 pts. MDR-1 expression appeared to be a characteristic feature in CD34+ AML (12/16 were CD34+ and MDR+ pts; p=0.013). No correlation, however, was found between chromosomal aberrations and MDR-1 expression. Pts with aberrations of either chromosomes 7, 8 or 5 detected by FISH (FISH+) were predominantly resistant to induction therapy (6/8 pts, p=0.004). A lower rate of complete remission (CR) was also seen in pts with MDR-1 expression (p=0.006). MDR+/FISH+ pts (n=3) were all refractory to remission induction, while all MDR-/FISH- pts (n=19) achieved CR (p=0.0006). MDR-1+ as well as pts with aberrations of chromosomes 7, and 5(q) showed a significantly decreased probability of overall survival. In conclusion, MDR-1 expression as well as abnormalities of chromosomes 7, and 5(q) predict poor clinical outcome in AML. The identification of these prognostic factors provides useful information for risk adapted treatment strategies.

Adult↗
PubMed2000

Treatment of Adult ALL according to protocols of the German Multicenter Study Group for Adult ALL (GMALL).

The German Multicenter Study Group for Adult Acute Lymphoblastic leukemia (GMALL) has conducted 5 consecutive trials with more than 3000 patients since 1981. This article provides an overview on aims, treatment concepts, and results of these studies. It includes brief summaries on the development of prognostic models within the GMALL group and on approaches for prophylaxis of CNS relapse, and it summarizes specific treatment concepts for mature B-lineage acute lymphocytic leukemia.

Adolescent↗