P Komminoth

Institut für Pathologie, Bern, BE, Switzerland

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Publications (100)410.94 Total impact

  • Article: TNM staging of neoplasms of the endocrine pancreas: results from a large international cohort study.
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    ABSTRACT: Both the European Neuroendocrine Tumor Society (ENETS) and the International Union for Cancer Control/American Joint Cancer Committee/World Health Organization (UICC/AJCC/WHO) have proposed TNM staging systems for pancreatic neuroendocrine neoplasms. This study aims to identify the most accurate and useful TNM system for pancreatic neuroendocrine neoplasms. The study included 1072 patients who had undergone previous surgery for their cancer and for which at least 2 years of follow-up from 1990 to 2007 was available. Data on 28 variables were collected, and the performance of the two TNM staging systems was compared by Cox regression analysis and multivariable analyses. All statistical tests were two-sided. Differences in distribution of sex and age were observed for the ENETS TNM staging system. At Cox regression analysis, only the ENETS TNM staging system perfectly allocated patients into four statistically significantly different and equally populated risk groups (with stage I as the reference; stage II hazard ratio [HR] of death = 16.23, 95% confidence interval [CI] = 2.14 to 123, P = .007; stage III HR of death = 51.81, 95% CI = 7.11 to 377, P < .001; and stage IV HR of death = 160, 95% CI = 22.30 to 1143, P < .001). However, the UICC/AJCC/WHO 2010 TNM staging system compressed the disease into three differently populated classes, with most patients in stage I, and with the patients being equally distributed into stages II-III (statistically similar) and IV (with stage I as the reference; stage II HR of death = 9.57, 95% CI = 4.62 to 19.88, P < .001; stage III HR of death = 9.32, 95% CI = 3.69 to 23.53, P = .94; and stage IV HR of death = 30.84, 95% CI = 15.62 to 60.87, P < .001). Multivariable modeling indicated curative surgery, TNM staging, and grading were effective predictors of death, and grading was the second most effective independent predictor of survival in the absence of staging information. Though both TNM staging systems were independent predictors of survival, the UICC/AJCC/WHO 2010 TNM stages showed very large 95% confidence intervals for each stage, indicating an inaccurate predictive ability. Our data suggest the ENETS TNM staging system is superior to the UICC/AJCC/WHO 2010 TNM staging system and supports its use in clinical practice.
    CancerSpectrum Knowledge Environment 04/2012; 104(10):764-77. · 14.07 Impact Factor
  • Article: Klassifikation gastroenteropankreatischer neuroendokriner Tumoren
    A. Perren, A. Schmitt, P. Komminoth, M. Pavel
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    ABSTRACT: Tumoren des disseminierten/diffusen neuroendokrinen Systems sind durch einen gemeinsamen Phänotyp gekennzeichnet. In ihrer Biologie unterscheiden sich neuroendokrine Tumoren (NET) jedoch bzgl. Morphologie, endokrinologischer Symptomatik und Ursprungsorgan. Die WHO-Klassifikation trägt diesen Unterschieden Rechnung und klassifiziert NET nach einem einheitlichen Vorgehen, wobei die Parameter Größe und Invasionstiefe je nach Ursprungsorgan variieren. Um die Nomenklatur weiter zu vereinheitlichen, wurde vor kurzem von der „European Neuroendocrine Tumor Society“ (ENETS) der Vorschlag einer TNM-Stadien-Einteilung und Graduierung gastroenteropankreatischer NET vorgelegt. Tumors of the disseminated/diffuse neuroendocrine system (NET) are characterized by a common phenotype. However, the biology varies according to histomorphology, endocrine symptoms and organ of origin. The WHO classification takes these differences into account and uses a common framework, where the parameters size and extent of invasion vary according to the organ of origin. In order to achieve a further standardization of reporting the European Neuroendocrine Tumor Society (ENETS) recently proposed a tumor-node-metastasis (TNM) staging and grading system for gastro-entero-pancreatic NET.
    Der Radiologe 04/2012; 49(3):198-205. · 0.61 Impact Factor
  • Article: [The ENETS and UICC TNM classification of neuroendocrine tumors of the gastrointestinal tract and the pancreas: comment].
    Der Pathologe 09/2010; 31(5):353-4. · 0.67 Impact Factor
  • Article: [Classification of gastro-entero-pancreatic neuroendocrine tumors].
    A Perren, A Schmitt, P Komminoth, M Pavel
    [show abstract] [hide abstract]
    ABSTRACT: Tumors of the disseminated/diffuse neuroendocrine system (NET) are characterized by a common phenotype. However, the biology varies according to histomorphology, endocrine symptoms and organ of origin. The WHO classification takes these differences into account and uses a common framework, where the parameters size and extent of invasion vary according to the organ of origin. In order to achieve a further standardization of reporting the European Neuroendocrine Tumor Society (ENETS) recently proposed a tumor-node-metastasis (TNM) staging and grading system for gastro-entero-pancreatic NET.
    Der Radiologe 03/2009; 49(3):198-205. · 0.61 Impact Factor
  • Source
    Article: TNM staging of midgut and hindgut (neuro) endocrine tumors: a consensus proposal including a grading system.
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    ABSTRACT: Criteria for the staging and grading of neuroendocrine tumors (NETs) of midgut and hindgut origin were established at the second Consensus Conference in Frascati (Rome) organized by the European Neuroendocrine Tumor Society (ENETS). The proposed tumor-node-metastasis (TNM) classifications are based on the recently published ENETS Guidelines for the Diagnosis and Treatment of gastroenteropancreatic NETs and follow our previous proposal for foregut tumors. The new TNM classifications for NETs of the ileum, appendix, colon, and rectum, and the grading system were designed, discussed, and consensually approved by all conference participants. These proposals need to be validated and are meant to help clinicians in the stratification, treatment and follow-up of patients.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 11/2007; 451(4):757-62. · 2.49 Impact Factor
  • Article: Allelic deletion of the MEN1 gene in duodenal gastrin and somatostatin cell neoplasms and their precursor lesions.
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    ABSTRACT: Patients with a multiple endocrine neoplasia type 1 (MEN1)-associated Zollinger-Ellison syndrome (ZES) show multifocal duodenal gastrinomas and precursor lesions. To test these lesions for loss of heterozygosity (LOH) of the MEN1 gene locus on chromosome 11q13, and to investigate whether the MEN1-related endocrine cell changes also involved somatostatin cells. Tissue specimens from six patients with MEN1 and ZES were analysed by immunohistochemistry and immunofluorescence. LOH analysis was performed by fluorescence in situ hybridisation (FISH), using probes containing the MEN1 gene locus and the centromere 11 (C11) region. For simultaneous analysis of hormones and allelic deletions, a combined FISH/immunofluorescence protocol was established. 28 of a total of 33 duodenal neuroendocrine tumours (NETs) were gastrin-producing tumours; 13/28 (46.4%) revealed LOH on 11q13 and/or C11. Five of the NETs were somatostatin-expressing tumours, two revealing LOH. Allelic loss was detected in tumours as small as 300 microm (gastrin) and 400 microm (somatostatin) in diameter. The gastrin-producing tumours showed different deletion/retention patterns. Hyperplastic somatostatin cell lesions, similar to those of the gastrin cells, were present in all patients. The hyperplastic lesions of both cell lines consistently retained both 11q13 alleles. Allelic deletion of the MEN1 gene may reflect a pivotal event in the development of multifocal gastrin and somatostatin cell neoplasms in the duodenum of patients with MEN1. The observation of distinct deletion patterns in small synchronous tumours supports the concept that each gastrin-producing tumour in an individual MEN1 patient arises from an independent cell clone.
    Gut 06/2007; 56(5):637-44. · 10.11 Impact Factor
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    Article: TNM staging of foregut (neuro)endocrine tumors: a consensus proposal including a grading system.
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    ABSTRACT: The need for standards in the management of patients with endocrine tumors of the digestive system prompted the European Neuroendocrine Tumor Society (ENETS) to organize a first Consensus Conference, which was held in Frascati (Rome) and was based on the recently published ENETS guidelines on the diagnosis and treatment of digestive neuroendocrine tumors (NET). Here, we report the tumor-node-metastasis proposal for foregut NETs of the stomach, duodenum, and pancreas that was designed, discussed, and consensually approved at this conference. In addition, we report the proposal for a working formulation for the grading of digestive NETs based on mitotic count and Ki-67 index. This proposal, which needs to be validated, is meant to help clinicians in the stratification, treatment, and follow-up of patients.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 11/2006; 449(4):395-401. · 2.49 Impact Factor
  • Article: Genetic Analyses of Apparently Sporadic Pheochromocytomas
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    ABSTRACT:  Pheochromocytomas (PCCs) are neuroendocrine tumors of chromaffin tissue that produce catecholamines. They are usually located in the adrenal medulla, although in about 10% the tumors arise from extra-adrenal chromaffin tissue. The majority of PCCs arise sporadically, but PCCs occur also in the context of hereditary cancer syndromes. Familial PCC is inherited as an autosomal dominant trait alone or as a component of the multiple endocrine neoplasia Type 2 (MEN2) syndrome (RET gene), Von Hippel–Lindau (VHL) disease (VHL gene), neurofibromatosis Type 1 (NF1 gene), or familial pheochromocytoma–paraganglioma (PCC–PGL) syndrome (SDHD/B and C genes). It has been reported that 24% of apparently sporadic PCCs patients harbor germline mutations in these PCC-causing genes. We investigated the contribution of the inherited PCC-causing genes in a partly retrospectively and partly prospectively obtained series of 213 apparently sporadic PCCs. Mutation analysis was performed for RET (56 cases), VHL (136 cases), and SDHD (126 cases) and SDHB (47 cases). No germline RET mutations, six (4.4%) germline VHL mutations, two (1.5%) germline SDHD mutations, and one germline (1.6%) SDHB mutation were found. In total we found germline mutations in about 7.5% of the investigated apparently sporadic PCCs. Although 7.5% germline mutations in a series of apparently sporadic PCCs are far less than the more than 20% reported in the literature, the figure is significant enough to consider germline mutation testing for each patient with PCC.
    Annals of the New York Academy of Sciences 09/2006; 1073(1):138 - 148. · 3.15 Impact Factor
  • Article: IGFII and MIB1 immunohistochemistry is helpful for the differentiation of benign from malignant adrenocortical tumours.
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    ABSTRACT: The differentiation of adrenocortical carcinomas from adenomas may be difficult based on morphology alone. Differential expression of insulin-like growth factor (IGF) II and cyclin-dependent kinase (CDK) 4 has recently been described in these tumours. The aim of this study was to investigate the diagnostic usefulness of these markers immunohistochemically. We examined 22 benign and 17 malignant adrenocortical tumours and compared IGFII and CDK4 expression with known immunohistochemical as well as morphological criteria of malignancy. Thirteen of 17 carcinomas showed immunohistochemical reactivity for IGFII, whereas all adenomas but one were negative. Intense CDK4 expression was detected in 11 of 17 carcinomas but was present in only three of 22 adenomas. The MIB1 index was >5% in 14 of 16 carcinomas and was <5% in all adenomas but one. The combination of IGFII immunohistochemistry with MIB1 index led to high sensitivity and specificity in detecting adrenocortical carcinomas. IGFII and MIB1 are helpful immunohistochemical markers to predict malignancy in adrenocortical neoplasms. These markers can be used in addition to clinical, gross and morphological features to establish a diagnosis in difficult cases.
    Histopathology 09/2006; 49(3):298-307. · 3.08 Impact Factor
  • Article: Genetic analyses of apparently sporadic pheochromocytomas: the Rotterdam experience.
    [show abstract] [hide abstract]
    ABSTRACT: Pheochromocytomas (PCCs) are neuroendocrine tumors of chromaffin tissue that produce catecholamines. They are usually located in the adrenal medulla, although in about 10% the tumors arise from extra-adrenal chromaffin tissue. The majority of PCCs arise sporadically, but PCCs occur also in the context of hereditary cancer syndromes. Familial PCC is inherited as an autosomal dominant trait alone or as a component of the multiple endocrine neoplasia Type 2 (MEN2) syndrome (RET gene), Von Hippel-Lindau (VHL) disease (VHL gene), neurofibromatosis Type 1 (NF1 gene), or familial pheochromocytoma-paraganglioma (PCC-PGL) syndrome (SDHD/B and C genes). It has been reported that 24% of apparently sporadic PCCs patients harbor germline mutations in these PCC-causing genes. We investigated the contribution of the inherited PCC-causing genes in a partly retrospectively and partly prospectively obtained series of 213 apparently sporadic PCCs. Mutation analysis was performed for RET (56 cases), VHL (136 cases), and SDHD (126 cases) and SDHB (47 cases). No germline RET mutations, six (4.4%) germline VHL mutations, two (1.5%) germline SDHD mutations, and one germline (1.6%) SDHB mutation were found. In total we found germline mutations in about 7.5% of the investigated apparently sporadic PCCs. Although 7.5% germline mutations in a series of apparently sporadic PCCs are far less than the more than 20% reported in the literature, the figure is significant enough to consider germline mutation testing for each patient with PCC.
    Annals of the New York Academy of Sciences 09/2006; 1073:138-48. · 3.15 Impact Factor
  • Article: PTEN gene loss, but not mutation, in benign and malignant phaeochromocytomas.
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    ABSTRACT: Mutations of the 'phosphatase and tensin homologue deleted on chromosome 10' (PTEN/MMAC1) gene have been associated with a variety of human cancers, including prostate cancer, glioblastoma, and melanoma. The gene is thought to be one of the most frequently mutated tumour suppressor genes and inactivation of PTEN is associated with disease progression and angiogenesis. High vascularization and resistance to chemo- and radio-therapy are two well-established features of phaeochromocytomas (PCCs). Furthermore, benign and malignant PCCs are found in several PTEN knockout mouse models. This study therefore evaluated whether inactivation of PTEN may be involved in the tumourigenesis of PCC in man and whether PTEN abnormalities may help to define the malignant potential of these tumours. Tumour and germline DNA was analysed from 31 patients with apparently sporadic PCC, including 14 clinically benign and 17 malignant tumours, for loss of the PTEN gene locus, mutations in the PTEN gene, and for PTEN protein expression by immunohistochemistry. Loss of heterozygosity (LOH) analysis showed loss of PTEN in four malignant tumours (40%) and in one benign tumour (14%). However, no mutations of PTEN were observed. Immunohistochemistry showed no correlation with clinical behaviour and/or LOH status. The results indicate that inactivation of the PTEN/MMAC1 gene may play a minor role in the development of malignant phaeochromocytomas.
    The Journal of Pathology 07/2006; 209(2):274-80. · 6.32 Impact Factor
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    Article: No mutations but an increased frequency of SDHx polymorphisms in patients with sporadic and familial medullary thyroid carcinoma.
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    ABSTRACT: Germline mutations of the three succinate dehydrogenase subunits SDHB, SDHC and SDHD have recently been associated with familial pheochromocytoma and paraganglioma. Several reasons make these genes candidate tumor suppressor genes for medullary thyroid carcinoma (MTC): (1) SDHB lies on chromosome 1p, the region known to be deleted most frequently in MTC, (2) MTCs develop from neural crest-derived cells, as do pheochromocytomas and paragangliomas and (3) patients with germline mutations of the Ret-protooncogene develop MTCs as well as pheochromocytomas, indicating a relationship of these tumors on a genetic level. Therefore, we attempted to determine whether the tumor suppressor genes SDHB, SDHC and SDHD are involved in sporadic and familial MTC. Somatic mutations of the SDH subunits were absent in all 35 investigated MTCs. Loss of heterozygosity was found in 27% (SDHB) and 4% (SDHD) respectively. While the frequency of non-coding, intronic polymorphisms did not differ in MTC patients compared with a control population, an accumulation of amino-acid coding polymorphisms (S163P in SDHB as well as G12S and H50R in SDHD) was found among MTC patients especially patients with familial tumors, suggesting a functional connection of coding SDH polymorphisms to activating Ret mutations.
    Endocrine Related Cancer 01/2006; 12(4):1011-6. · 4.36 Impact Factor
  • Article: Chromosomal instability predicts metastatic disease in patients with insulinomas.
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    ABSTRACT: Endocrine pancreatic tumors (EPTs) comprise a highly heterogeneous group of tumors with different clinical behavior and genetic makeup. Insulinomas represent the predominant syndromic subtype of EPTs. The metastatic potential of insulinomas can frequently not be predicted using histopathological criteria, and also molecular markers indicating malignant progression are unreliable because of the small number of cases per subtype studied so far. For the identification of reliable indicators of metastatic disease, we investigated 62 sporadic insulinomas (44 benign and 18 tumors with metastases) by means of comparative genomic hybridization (CGH). In addition, the role of MEN1 (multiple endocrine neoplasia type 1) gene mutations was determined to assess specific chromosomal alterations associated with dysfunction of this endocrine tumor-related tumor suppressor gene. Only one case with a somatic MEN1 mutation was identified (1527del7bp), indicating that the MEN1 gene plays a minor pathogenic role in sporadic insulinomas. CGH analysis revealed that the total number of aberrations per tumor differs strongly between the benign and the malignant group (4.2 vs 14.1; P<0.0001). Furthermore, chromosome 9q gain was found to be the most frequent aberration in both benign and malignant insulinomas, whereas chromosome 6q losses and 12q, 14q and 17pq gains are strongly associated with metastatic disease. Our study shows that chromosomal instability, as defined by > or =5 gains together with > or =5 losses, or total number of gains and losses > or =8, rather than parameters such as tumor size and proliferation index, is the most powerful indicator for the development of metastatic disease in patients with sporadic insulinoma.
    Endocrine Related Cancer 06/2005; 12(2):435-47. · 4.36 Impact Factor
  • Article: BRAF and endocrine tumors: mutations are frequent in papillary thyroid carcinomas, rare in endocrine tumors of the gastrointestinal tract and not detected in other endocrine tumors.
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    ABSTRACT: The tumorigenesis of sporadic endocrine tumors is still not fully understood. Activating point mutations of the serine/threonine kinase gene BRAF located on 7q34 are found in a wide range of malignancies, with the highest frequency (66%) occurring in malignant melanomas. Melanomas are tumors of neural-crest-derived cells as are medullary thyroid carcinomas, pheochromocytomas and paragangliomas. BRAF has not been examined in endocrine tumors of the diffuse neuroendocrine system or of neural-crest-derived cells. We examined 130 endocrine tumors of the pancreas, parathyroid gland, adrenal medulla, paraganglia, lung and gastrointestinal tract as well as follicular and c-cell-derived thyroid tumors. We found a high rate of V559E mutations in papillary thyroid carcinomas (47%), one V599E mutation in a well-differentiated gastric endocrine carcinoma (malignant carcinoid), but no activating BRAF mutations in all other endocrine tumors examined. These results point towards different pathways in tumorigenesis of endocrine tumors of various localizations and only rare involvement of the MAP kinase (MAPK) pathway in a subset of malignant neuroendocrine tumors.
    Endocrine Related Cancer 01/2005; 11(4):855-60. · 4.36 Impact Factor
  • Article: Spitzoid malignant melanoma with lymph-node metastasis. Is a copy-number loss on chromosome 6q a marker of malignancy?
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    ABSTRACT: Distinction of spitzoid malignant melanomas (SMM) from Spitz nevi may be difficult or even impossible on the basis of conventional histology. In this report, a patient suffering from a primary lesion diagnosed as a Spitz nevus and a metastatic malignant melanoma approximately 4 years thereafter is described. A diagnosis of SMM was made subsequently upon review of the primary lesion. In the present analysis, we used comparative genomic hybridization (CGH) to define markers characteristic of SMM. The primary lesion revealed deletions on chromosomes 6q and 9p. In the metastasis, additional deletions on chromosomes 10p and 10q and gains of chromosome 7 were found. To our knowledge, no chromosomal aberration on chromosome 6 was hitherto demonstrated in benign melanocytic nevi. Findings reported in the literature suggest that human melanoma metastasis suppressor gene maps to 6q. In contrast, losses on chromosome 9p seem to be an early event in the development of melanoma. However, they are not only found in melanomas but are occasionally present in Spitz nevi as well as in atypical nevi. The CGH result with deletion of 6q in this difficult to diagnose primary melanocytic lesion strongly supports the diagnosis of malignant melanoma. To demonstrate the reliability of loss on chromosome 6q as a marker of SMM, a larger number of lesions must be investigated.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 01/2002; 439(6):823-6. · 2.49 Impact Factor
  • Article: Genomic imbalances in the progression of endocrine pancreatic tumors.
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    ABSTRACT: Endocrine pancreatic tumors (EPTs) are neoplasms with malignant potential. To explore the molecular basis of metastatic progression in human EPTs, we analyzed 17 paired specimens of primary EPTs and their metastases and 28 nonmetastatic EPTs using comparative genomic hybridization (CGH). Genomic alterations were detected in all of the matched primary/metastatic tumors and 19 (58%) nonmetastatic EPTs. The mean number of genomic changes was 17.3 in metastases, 12.5 in their primary tumors, and 4.5 in nonmetastatic EPTs. Statistical analysis of shared genomic changes in matched pairs of primary tumors and metastases showed a high probability (>95%) of a clonal relationship in 15 of the 17 cases. A closely related genetic pattern was also demonstrated on the basis of concordance analysis of the two groups. The most striking genomic changes which were enriched in metastases included gains of chromosomes 4 and 7 and losses of 21q. Other common regions of frequent losses (>40%) identified in metastases and/or their primary tumors involved 2p, 2q, 3p, 3q, 6q, 10p, and 11p, whereas frequently detected gains (>40%) in the paired tumors involved 5p, 5q, 12q, 14q, 17q, 18q, and 20q. These chromosomal aberrations were found in significantly fewer nonmetastatic EPTs. Some of these chromosomal loci may harbor genes contributing to the progression of EPT.
    Genes Chromosomes and Cancer 01/2002; 32(4):364-72. · 3.31 Impact Factor
  • Article: Deletion at 3p25.3-p23 is frequently encountered in endocrine pancreatic tumours and is associated with metastatic progression.
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    ABSTRACT: For several reasons, chromosome 3p is thought to be involved in the pathogenesis of sporadic endocrine pancreatic tumours (EPTs): von Hippel-Lindau's disease (VHL gene at 3p25.5) is associated with EPTs; 3p is frequently involved in solid human tumours; and comparative genomic hybridization has identified frequent losses at 3p in EPTs. This study investigated 99 benign and malignant tumours, including 20 metastases, from 82 patients, by microsatellite loss of heterozygosity (LOH) analysis and fluorescence in situ hybridization (FISH) in order to evaluate the importance of chromosome 3p deletions in the molecular pathogenesis and biological behaviour of EPTs, to elaborate a common region of deletion, and to narrow down putative tumour suppressor gene loci. Allelic losses of 3p were found in 58/99 (58.6%) of tumours in 45/82 (54.9%) patients; analysis of seven microsatellite markers (3p26-p21) revealed a common region of LOH at 3p25.3-p23. The LOH frequency was significantly higher in malignant than in benign neoplasms (70.2% versus 28.0%; p=0.001). In addition, a strong correlation was found between the loss of alleles on chromosome 3p and clinically metastatic disease (LOH of 73.7% in metastasizing versus 41.5% in non-metastasizing tumours; p=0.008). EPTs from these patients showed a tendency towards losing large parts or the entire short arm of chromosome 3 with tumour progression. Furthermore, FISH analysis revealed complete loss of chromosome 3 in ten out of 37 EPTs (27%). These results indicate that a putative tumour suppressor gene at 3p25.3-p23 may play a role in the oncogenesis of sporadic EPTs and that losses of larger centromeric regions are associated with metastatic progression.
    The Journal of Pathology 09/2001; 194(4):451-8. · 6.32 Impact Factor
  • Article: Differential loss of chromosome 11q in familial and sporadic parasympathetic paragangliomas detected by comparative genomic hybridization.
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    ABSTRACT: Parasympathetic paragangliomas (PGLs) represent neuroendocrine tumors arising from chief cells in branchiomeric and intravagal paraganglia, which share several histological features with their sympathetic counterpart sympathoadrenal paragangliomas. In recent years, genetic analyses of the familial form of PGL have attracted considerable interest. However, the majority of paragangliomas occurs sporadically and it remains to be determined whether the pathogenesis of sporadic paraganglioma resembles that of the familial form. Furthermore, data on comparative genetic aberrations are scarce. To provide fundamental cytogenetic data on sporadic and hereditary PGLs, we performed comparative genomic hybridization using directly fluorochrome-conjugated DNA extracted from 12 frozen and 4 paraffin-embedded tumors. The comparative genomic hybridization data were extended by loss of heterozygosity analysis of chromosome 11q. DNA copy number changes were found in 10 (63%) of 16 tumors. The most frequent chromosomal imbalance involved loss of chromosome 11. Six of seven familial tumors and two of nine sporadic tumors showed loss of 11q (86% versus 22%, P = 0.012). Deletions of 11p and 5p were found in two of nine sporadic tumors. We conclude that overall DNA copy number changes are infrequent in PGLs compared to sympathetic paragangliomas and that loss of chromosome 11 may be an important event in their tumorigenesis, particularly in familial paragangliomas.
    American Journal Of Pathology 07/2001; 158(6):1937-42. · 4.89 Impact Factor
  • Article: Genetic evidence for early divergence of small functioning and nonfunctioning endocrine pancreatic tumors: gain of 9Q34 is an early event in insulinomas.
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    ABSTRACT: The malignant potential among endocrine pancreatic tumors (EPTs) varies greatly and can frequently not be predicted using histopathological parameters. Thus, molecular markers that can predict the biological behavior of EPTs are required. In a previous comparative genomic hybridization study, we observed marked genetic differences between the various EPT subtypes and a correlation between losses of 3p and 6 and gains of 14q and Xq and metastatic disease. To search for genetic alterations that play a role during early tumor development, we have studied 38 small (< or =2 cm) EPTs, including 24 insulinomas and 10 nonfunctioning EPTs. Small EPTs are usually classified as clinically benign tumors in the absence of histological signs of malignancy. Using comparative genomic hybridization, we identified chromosomal aberrations in 27 EPTs (mean, 4.1). Interestingly, the number of gains differed strongly between nonfunctioning and functioning EPTs (3.4 versus 1.5, respectively; P = 0.0526), as did the number of aberrations in the benign (n = 30) and malignant (n = 8) tumors (3 versus 8.4, respectively; P = 0.0022). In the insulinomas, 9q gain (common region of involvement: 9q34) was most common (50%) and in nonfunctioning EPTs, gain of 4p was most common (40%). Most frequent losses in insulinomas involved 1p (20.8%), 1q, 4q, 11q, Xq, and Y (all 16.7%) and in nonfunctioning EPTs, 6q. Losses of 3pq and 6q and gains of 17pq and 20q proved to be strongly associated with malignant behavior in all of the small EPTs (P < or = 0.0219). Our results demonstrate marked genetic differences between small functioning and nonfunctioning EPTs, indicating that these subtypes evolve along different genetic pathways. In addition, our study endorses the importance of chromosomes 3 and 6q losses to discriminate EPTs with a malignant behavior from benign ones.
    Cancer Research 07/2001; 61(13):5186-92. · 7.86 Impact Factor
  • Article: Putative tumor suppressor loci at 6q22 and 6q23-q24 are involved in the malignant progression of sporadic endocrine pancreatic tumors.
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    ABSTRACT: Our previous comparative genomic hybridization study on sporadic endocrine pancreatic tumors (EPTs) revealed frequent losses on chromosomes 11q, 3p, and 6q. The aim of this study was to evaluate the importance of 6q losses in the oncogenesis of sporadic EPTs and to narrow down the smallest regions of allelic deletion. A multimodal approach combining polymerase chain reaction-based allelotyping, double-target fluorescence in situ hybridization, and comparative genomic hybridization was used in a collection of 109 sporadic EPTs from 93 patients. Nine polymorphic microsatellite markers (6q13 to 6q25-q27) were investigated, demonstrating a loss of heterozygosity (LOH) in 62.2% of the patients. A LOH was significantly more common in tumors >2 cm in diameter than below this threshold as well as in malignant than in benign tumors. We were able to narrow down the smallest regions of allelic deletion at 6q22.1 (D6S262) and 6q23-q24 (D6S310-UTRN) with LOH-frequencies of 50.0% and 41.2 to 56.3%, respectively. Several promising tumor suppressor candidates are located in these regions. Additional fluorescence in situ hybridization analysis on 46 EPTs using three locus-specific probes (6q21, 6q22, and 6q27) as well as a centromere 6-specific probe revealed complete loss of chromosome 6 especially in metastatic disease. We conclude that the two hot spots found on 6q may harbor putative tumor suppressor genes involved not only in the oncogenesis but maybe also in the malignant and metastatic progression of sporadic EPTs.
    American Journal Of Pathology 06/2001; 158(6):1903-11. · 4.89 Impact Factor

Institutions

  • 2012
    • Institut für Pathologie
      Bern, BE, Switzerland
    • Università Cattolica del Sacro Cuore
      • Institute of Pathological Anatomy
      Roma, Latium, Italy
  • 2006–2007
    • Università degli studi di Parma
      Parma, Emilia-Romagna, Italy
  • 1989–2005
    • Universität Zürich
      • • Institut für Klinische Pathologie
      • • Internal Medicine Unit
      Zürich, ZH, Switzerland
  • 2001
    • Erasmus MC
      Rotterdam, South Holland, Netherlands
  • 2000–2001
    • Maastricht University
      • Genetica en Celbiologie
      Maastricht, Provincie Limburg, Netherlands
  • 1999–2001
    • The Ohio State University
      • The James Comprehensive Cancer Center
      Columbus, OH, USA
    • Università degli Studi di Torino
      Torino, Piedmont, Italy
  • 1997
    • Technische Universität München
      München, Bavaria, Germany
    • Institut für Pathologie und Molekularpathologie
      Gelsenkirchen, North Rhine-Westphalia, Germany
    • Dana-Farber Cancer Institute
      Boston, MA, USA
  • 1996–1997
    • Medizinische Hochschule Hannover
      • Institute for Pathology
      Hannover, Lower Saxony, Germany
    • Universität zu Lübeck
      • Department of Paediatrics
      Lübeck, Schleswig-Holstein, Germany
  • 1992–1997
    • Tufts Medical Center
      • Department of Medicine
      Boston, MA, USA
    • University of Massachusetts Medical School
      • Department of Pathology
      Worcester, MA, USA
  • 1992–1993
    • Tufts University
      • Department of Medicine
      Medford, MA, USA
  • 1988–1990
    • Universität Basel
      Basel, BS, Switzerland