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Birt-Hogg-Dubé (BHD) syndrome is a cancer disorder caused by a pathogenic FLCN mutation characterized by fibrofolliculomas, lung cysts, pneumothorax, benign renal cyst, and renal cell carcinoma (RCC). In this case we describe a patient with bilateral renal tumour and a positive familial history for pneumothorax and renal cancer. Based on this clinical presentation, the patient was suspected for BHD syndrome, which was confirmed after molecular testing. We discuss the importance of recognizing this autosomal dominant cancer disorder when a patient is presented at the urologist with a positive family history of chromophobe renal cell cancer or a positive familial history for renal cell cancer and pneumothorax. [ABSTRACT FROM AUTHOR]

Background: Birt-Hogg-Dubé (BHD) syndrome is an autosomal dominant condition caused by germline FLCN mutations, and characterised by fibrofolliculomas, pneumothorax and renal cancer. The renal cancer risk, cancer phenotype and pneumothorax risk of BHD have not yet been fully clarified. The main focus of this study was to assess the risk of renal cancer, the histological subtypes of renal tumours and the pneumothorax risk in BHD.Methods: In this study we present the clinical data of 115 FLCN mutation carriers from 35 BHD families.Results: Among 14 FLCN mutation carriers who developed renal cancer 7 were <50 years at onset and/or had multifocal/bilateral tumours. Five symptomatic patients developed metastatic disease. Two early-stage cases were diagnosed by surveillance. The majority of tumours showed characteristics of both eosinophilic variants of clear cell and chromophobe carcinoma. The estimated penetrance for renal cancer and pneumothorax was 16% (95% minimal confidence interval: 6-26%) and 29% (95% minimal confidence interval: 9-49%) at 70 years of age, respectively. The most frequent diagnosis in families without identified FLCN mutations was familial multiple discoid fibromas.Conclusion: We confirmed a high yield of FLCN mutations in clinically defined BHD families, we found a substantially increased lifetime risk of renal cancer of 16% for FLCN mutation carriers. The tumours were metastatic in 5 out of 14 patients and tumour histology was not specific for BHD. We found a pneumothorax risk of 29%. We discuss the implications of our findings for diagnosis and management of BHD. [ABSTRACT FROM AUTHOR]

Johannesma PC, van der Klift HM, van Grieken NCT, Troost D, te Riele H, Jacobs MAJM, Postma TJ, Heideman DAM, Tops CMJ, Wijnen JT, Menko FH. Childhood brain tumours due to germline bi-allelic mismatch repair gene mutations. Childhood brain tumours may be due to germline bi-allelic mismatch repair (MMR) gene mutations in MLH1, MSH2, MSH6 or PMS2. These mutations can also lead to colorectal neoplasia and haematological malignancies. Here, we review this syndrome and present siblings with early-onset rectal adenoma and papillary glioneural brain tumour, respectively, due to novel germline bi-allelic PMS2 mutations. Identification of MMR protein defects can lead to early diagnosis of this condition. In addition, assays for these defects may help to classify brain tumours for research protocols aimed at targeted therapies. [ABSTRACT FROM AUTHOR]

Smit DL, Mensenkamp AR, Badeloe S, Breuning MH, Simon MEH, van Spaendonck KY, Aalfs CM, Post JG, Shanley S, Krapels IPC, Hoefsloot LH, van Moorselaar RJA, Starink TM, Bayley J-P, Frank J, van Steensel MAM, Menko FH. Hereditary leiomyomatosis and renal cell cancer in families referred for fumarate hydratase germline mutation analysis. Heterozygous fumarate hydratase ( FH) germline mutations cause hereditary leiomyomatosis and renal cell cancer (HLRCC), an autosomal dominant syndrome characterized by multiple cutaneous piloleiomyomas, uterine leiomyomas and papillary type 2 renal cancer. The main objective of our study was to evaluate clinical and genetic data from families suspected of HLRCC on a nationwide level. All families referred for FH mutation analysis in the Netherlands were assessed. We performed FH sequence analysis and multiplex ligation-dependent probe amplification. Families with similar FH mutations were examined for haplotype sharing. In 14 out of 33 families, we identified 11 different pathogenic FH germline mutations, including 4 novel mutations and 1 whole-gene deletion. Clinical data were available for 35 FH mutation carriers. Cutaneous leiomyomas were present in all FH mutation carriers older than 40 years of age. Eleven out of 21 female FH mutation carriers underwent surgical treatment for symptomatic uterine leiomyomas at an average of 35 years. Two FH mutation carriers had papillary type 2 renal cancer and Wilms' tumour, respectively. We evaluated the relevance of our findings for clinical practice and have proposed clinical diagnostic criteria, indications for FH mutation analysis and recommendations for management. [ABSTRACT FROM AUTHOR]

AIMS: Ductal carcinoma in situ (DCIS) is an established late precursor of sporadic invasive breast cancer and to a large extent parallels its invasive counterpart with respect to molecular changes and immunophenotype. Invasive breast cancers in germline BRCA1 and BRCA2 mutation carriers have a distinct "basal" and "luminal" immunophenotype, respectively, but the immunophenotype of their precursor lesions has hardly been studied, and this was the aim of this study. METHODS: DCIS lesions of 25 proven BRCA1 and 9 proven BRCA2 germline mutation carriers and their 22 and 6, respectively, accompanying invasive lesions were stained by immunohistochemistry for oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER)2/neu, cytokeratin (CK)5/6, CK14, epidermal growth factor receptor (EGFR) and Ki67. RESULTS: DCIS lesions in BRCA1 mutation carriers were mostly of the basal molecular type with low ER/PR/HER2 expression, while they frequently expressed CK5/6, CK14 and EGFR, and were mostly grade 3 and highly proliferative. DCIS lesions in BRCA2 mutation carriers were mostly of luminal molecular type with frequent expression of ER/PR, and infrequent expression of CK5/6, CK14 and EGFR, and they were mostly grade 3 and showed low proliferation. In BRCA1 and BRCA2 mutation carriers there was a high concordance between DCIS lesions and their concomitant invasive counterpart with regard to expression of individual markers as well as "molecular" subtype. CONCLUSIONS: Although the number of cases studied was low, DCIS lesions in BRCA1 and BRCA2 mutations carriers are usually of the basal and luminal molecular type, respectively, similar to their accompanying invasive cancers, thereby providing evidence that DCIS is a direct precursor lesion in these hereditary predisposed patients. This also suggests that crucial carcinogenetic events leading to these phenotypes in hereditary predisposed patients occur before the stage of invasion. [ABSTRACT FROM AUTHOR]

Background: In BRCA2 mutation carriers, increased risks have been reported for several cancer sites besides breast and ovary. As most of the families included in earlier reports were selected on the basis of multiple breast/ovarian cancer cases, it is possible that risk estimates may differ in mutation carriers with a less striking family history. Methods: In the Netherlands, 139 BRCA2 families with 66 different pathogenic mutations were included in a nationwide study. To avoid testing bias, we chose not to estimate risk in typed carriers, but rather in male and female family members with a 50% prior probability of being a carrier (n=1811). The relative risk (RR) for each cancer site with the exception of breast and ovarian cancer was determined by comparing observed numbers with those expected, based on Dutch cancer incidence rates. Results: We observed an excess risk for four cancer sites: pancreas (RR 5.9; 95% confidence interval (CI) 3.2 to 10.0), prostate (2.5; 1.6 to 3.8), bone (14.4; 2.9 to 42.1) and pharynx (7.3; 2.0 to 18.6). A small increase was observed far cancer of the digestive tract (1.5; 1.1 to 1.9). Histological verification was available for 46% of the tumours. Nearly all increased risks reached statistical significance for men only. Cancer risks tended to be higher far people before the age of 65 years. Moreover, families with mutations outside the previously defined ovarian cancer cluster region tended to have a higher cancer risk. Conclusions: We found that BRCA2 carriers are at increased risk far cancers of the prostate and pancreas, and possibly bone and pharynx. Larger databases with extended fallow up are needed to provide insight into mutation specific risks of selected carriers in BRCA2 families. [ABSTRACT FROM AUTHOR]

Hereditary non-polyposis colorectal cancer is an autosomal dominant condition due to germline mutations in DNA-mismatch-repair genes, in particular MLH1, MSH2 and MSH6. Here we describe the application of a novel technique for the detection of genomic deletions in MLH1 and MSH2. This method, called multiplex ligation-dependent probe amplification, is a quantitative multiplex PCR approach to determine the relative copy number of each MLH1 and MSH2 exon. Mutation screening of genes was performed in 126 colorectal cancer families selected on the basis of clinical criteria and in addition, for a subset of families, the presence of microsatellite instability (MSI-high) in tumours. Thirty-eight germline mutations were detected in 37 (29.4%) of these kindreds, 31 of which have a predicted pathogenic effect. Among families with MSI-high tumours 65.7% harboured germline gene defects. Genomic deletions accounted for 54.8% of the pathogenic mutations. A complete deletion of the MLH1 gene was detected in two families. The multiplex ligation-dependent probe amplification approach is a rapid method for the detection of genomic deletions in MLH1 and MSH2. In addition, it reveals alterations that might escape detection using conventional diagnostic techniques. Multiplex ligation-dependent probe amplification might be considered as an early step in the molecular diagnosis of hereditary non-polyposis colorectal cancer. [ABSTRACT FROM AUTHOR]

Objectives: Our purpose was to determine the prevalence of BRCA1 and BRCA2 germline mutations among patients from ovarian cancer families and to evaluate age at diagnosis, histologic diagnosis, and International Federation of Gynecology and Obstetrics stage in this group.Study Design: We reviewed 50 ovarian cancer patients from 30 ovarian cancer families and compared relevant clinical characteristics with those of a cancer registry reference group. BRCA1 (exons 2 to 24) and BRCA2 (exon 11) germline mutations were detected by a protein truncation test and sequencing of BRCA1 exon 2 (185delAG mutation) in 25 of the 30 families.Results: Ten (40%) of 25 families tested revealed a germline BRCA1 or BRCA2 mutation. Patients with ovarian cancer from the study group were young with an advanced International Federation of Gynecology and Obstetrics stage at diagnosis and had a relatively high frequency of serous adenocarcinoma.Conclusion: Direct mutation analysis of BRCA1 and BRCA2 revealed a high frequency of germline mutations in ovarian cancer families. Some clinical characteristics of hereditary ovarian cancer may differ from those of sporadic disease. [ABSTRACT FROM AUTHOR]

The article discusses a study that analyzes a novel GATA2 mutation in a large family using Sanger sequencing of peripheral blood DNA. It reveals two novel mutations located within exon two in which one was caused by the deletion of a single pair resulting in a frameshift at amino acid 28 (G28fs) and second was a missence mutation (H26P). It indicates that the large family of highly illustrative for the clinical variability and difficulty in predicting outcome in GATA2 mutation carriership.