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Query: UMLS:C1140680 (ovarian cancer)
 28,141 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An unknown fraction of the ovarian cancer burden occurs in women with a family history indicative of a putative autosomal dominantly inherited cancer susceptibility syndrome. The results from a five-generation, extended, hereditary breast-ovarian cancer kindred are described 10 years after it was initially ascertained. Significantly more cancers were observed in high-risk family members during this decade than were expected (P less than 0.001). The age of ovarian cancer diagnosis was studied in additional ovarian cancer-prone families of three types: site-specific ovarian cancer syndrome, the breast-ovarian cancer syndrome, and Lynch syndrome II. The age of onset in each of the three sets was significantly (P less than 0.001) earlier than the general population mean of 59, and there were significant differences in the age of onset (P = 0.050) among these three cohorts. Ovarian cancer histology was similar to that of patients with negative family histories. There may be clinically significant heterogeneity in the age at diagnosis of ovarian cancer among these ovarian cancer-prone syndromes. This has important implications for understanding its natural history and targeting surveillance-management strategies.
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PMID:Hereditary ovarian cancer. Heterogeneity in age at diagnosis. 199 14

Only a small proportion of cancers, arising in inherited syndromes such as polyposis coli, have an unequivocally inherited basis. Nevertheless, most common cancers show familial clustering, much of which may be due to inherited predisposition. If so, there may be wide variation in genetic susceptibility to common cancers. The precise models of susceptibility are unclear, but for ovarian cancer and breast cancer there is some evidence that a small proportion of cases result from highly penetrant dominant genes. This has been confirmed recently for breast cancer by genetic linkage studies. Clear evidence for genetic susceptibility has been obtained for Hodgkin's disease and nasopharyngeal carcinoma, where the existence of susceptibility genes at the HLA locus has been demonstrated by linkage analysis. These genes could account for the majority of cases of these cancers. Identification of other cancer susceptibility genes should be possible, either directly using linkage analysis, or through identification of constitutional phenotypes related to cancer risk.
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PMID:The contribution of inherited predisposition to cancer incidence. 210 19

In a previous study of alpha-L-fucosidase (ALF) activities in plasma samples from three ovarian cancer-prone kindreds, we observed a significant inverse correlation of cancer susceptibility and enzyme activity. Because a low level of plasma ALF activity is an inherited characteristic that has been termed the "fucosidase variant," the above demonstration has provoked great interest in the fucosidase variant relative to the genetic transmission of ovarian cancer susceptibility. We have now observed in these same plasma samples that the concentrations of lipid-associated sialic acid (LAS) are also inversely correlated with the ALF activities and, therefore, directly correlated with ovarian cancer susceptibility. In the fucosidase variant individual, the ALF is modified intracellularly, but the modified enzyme only exhibits decreased activity in the plasma. For this reason, ALF cannot be involved in tumorigenesis. Rather, the factor that modifies ALF is probably involved and is the inherited character. Therefore, we hypothesize that this modifier is responsible not only for the "fucosidase variant" but also for the elevated concentration of LAS and plays a role in hereditary ovarian cancer.
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PMID:alpha-L-fucosidase variant and lipid-associated sialic acid in hereditary ovarian cancer. 347 Jan 14

Genetic epidemiological evidence suggests that mutations in BRCA1 may be responsible for approximately one half of early onset familial breast cancer and the majority of familial breast/ovarian cancer. The recent cloning of BRCA1 allows for the direct detection of mutations, but the feasibility of presymptomatic screening for cancer susceptibility is unknown. We analyzed genomic DNA from one affected individual from each of 24 families with at least three cases of ovarian or breast cancer, using SSCP assays. Variant SSCP bands were subcloned and sequenced. Allele-specific oligonucleotide hybridization was used to verify sequence changes and to screen DNA from control individuals. Six frameshift and two missense mutations were detected in 10 different families. A frameshift mutation was detected in a male proband affected with both breast and prostate cancer. A 40-bp deletion was detected in a patient who developed intra-abdominal carcinomatosis 1 year after prophylactic oophorectomy. Mutations were detected throughout the gene, and only one was detected in more than a single family. These results provide further evidence that inherited breast and ovarian cancer can occur as a consequence of a wide array of BRCA1 mutations. These results suggests that development of a screening test for BRCA1 mutations will be technically challenging. The finding of a mutation in a family with male breast cancer, not previously thought to be related to BRCA1, also illustrates the potential difficulties of genetic counseling for individuals known to carry mutations.
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PMID:Detection of eight BRCA1 mutations in 10 breast/ovarian cancer families, including 1 family with male breast cancer. 761 Dec 77

A gene for hereditary breast and ovarian cancer, BRCA1, has been mapped to chromosome 17q12-q21. This gene is responsible for cancer susceptibility in the majority of families with multiple cases of ovarian cancer and early-onset breast cancer. We report linkage results of a family with 10 cases of breast cancer and a single case of ovarian cancer. A recombinant event in this family places BRCA1 distal (telomeric) to the locus EDH17B2, which codes for the enzyme estradiol 17 beta-dehydrogenase II. This recombinant is based on the appearance of breast cancer in a 45 year old woman. Under our genetic model, we estimate the probability that this woman carries a BRCA1 mutation to be 94%. These data further reduce the region of assignment of BRCA1 on chromosome 17q12-q21 and should expedite positional cloning of this important gene.
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PMID:The gene for hereditary breast-ovarian cancer, BRCA1, maps distal to EDH17B2 in chromosome region 17q12-q21. 783 28

Studies of familial breast and ovarian cancer have traditionally been directed towards a single type of cancer, but recent evidence leads us to consider these two types of cancer together. The original evidence for a common hereditary basis for breast and ovarian cancer comes from the observation of large families with several cases of both types. The number of cancers in these families was too great to be explained by chance and none of the known environmental risk factors are sufficient to account for the clustering. Statistical analysis performed on a number of breast-ovary cancer families identified by Dr Henry Lynch and his colleagues led them to conclude that the clustering could be explained by the effect of a single dominant gene. Women with breast cancer are at increased risk of developing a second primary cancer of the ovary; and relatives of women with breast or ovarian cancer are at roughly double the risk for either tumour. The most convincing evidence, however, for a common predisposition for breast and ovarian cancer comes from genetic linkage studies. In a linkage study cancer susceptibility in a family is shown to be transmitted with a particular allele of genetic marker of known chromosomal location. A gene from chromosome region 17q12-q21, designated BRCA1, identified in 1990 by Dr Mary-Claire King and colleagues, predisposes to both cancer of the breast and the ovary.
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PMID:Genetics of breast and ovarian cancer. 798 46

The breast and ovarian cancer susceptibility gene, BRCA1, has been cloned and shown to encode a zinc-finger protein of unknown function. Mutations in BRCA1 account for at least 80% of families with both breast and ovarian cancer, as well as some non-familial sporadic ovarian cancers. The loss of wild-type BRCA1 in tumours of individuals carrying one nonfunctional BRCA1 allele suggests that BRCA1 encodes a tumour suppressor that may inhibit the proliferation of mammary epithelial cells. To examine the role of BRCA1 in normal tissue growth and differentiation, and to generate a potential model for the cancer susceptibility associated with loss of BRCA1 function, we have created a mouse line carrying a mutation in one Brca1 allele. Analysis of mice homozygous for the mutant allele indicate that Brca1 is critical for normal development, as these mice died in utero between 10 and 13 days of gestation (E10-E13). Abnormalities in Brca1-deficient embryos were most evident in the neural tube, with 40% of the embryos presenting with varying degrees of spina bifida and anencephaly. In addition, the neuroepithelium in Brca1-deficient embryos appeared disorganized, with signs of both rapid proliferation and excessive cell death.
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PMID:Brca1 deficiency results in early embryonic lethality characterized by neuroepithelial abnormalities. 856 59

Breast cancer is the most common form of cancer in women in the U.S. The risk factors for developing breast cancer include increasing age, a family history of breast cancer, and the lack of a child by age 30. A substantial fraction of breast cancer, however, occurs in women who have no identifiable risk factors. The diagnosis, pathology, treatment, and presymptomatic testing of cancer susceptibility genes are reviewed. Syndromes with an associated risk of breast cancer are described, such as hereditary breast-ovarian cancer syndrome, Li-Fraumeni syndrome, ataxia telangiectasia, and Cowden's disease. With the localization of the BRCA1 gene to chromosome 17q21 and the BRCA2 gene to chromosome 13q12, issues surrounding breast cancer susceptibility genetic testing are assuming an ever greater measure of importance. The sensitivity and specificity for molecular testing of cancer susceptibility genes, however, have not been well defined. The progress in presymptomatic genetic testing is further hampered by various factors such as the technical difficulty in distinguishing mutations from polymorphisms, the number of different mutations identified thus far and the possibility of false positive and false negative results. Laboratory quality assurance/quality control issues are of paramount importance to avoid misleading interpretations. Many issues surrounding genetic screening and testing, such as insurance and employment discrimination, privacy, and informed consent, are under active debate, and guidelines and standards are under active development. It is therefore important to proceed with caution, so that irreversible harm resulting from data misinterpretation can be avoided.
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PMID:Clinical and research issues in breast cancer genetics. 887 57

A family history for breast cancer appears to be a major risk factor for breast cancer. It has been estimated that 5% of all breast cancers are hereditary. In the last five years much progress has been made in the identification of genes responsible for breast cancer. Much interest is focused on the BRCA-1 gene, which is associated with early onset breast and ovarian cancers. Heterogeneity within and across families in the pattern of cancer susceptibility has suggested that different susceptibility alleles may exist. The BRCA-1 gene has been cloned but the function of its product has not been determined. BRCA-1 mutations seem not to be involved in sporadic breast cancer. A second breast cancer susceptibility gene, BRCA-2, has been localized to chromosome 13q12-q13 but has not been identified as yet. Loss of heterozygosity of 13q is observed in 25% of sporadic breast tumors, which indicates that BRCA-2 might be a tumor suppressor gene. BRCA-2 confers only a low ovarian cancer risk. The TP53 gene has also been associated with breast cancer but to a much more limited extent than BRCA-1. Germline TP53 mutations have been found in patients with familial breast cancer. Other genes that have been associated with breast cancer risk are the androgen receptor (AR) gene and the ataxia teleangiectasia (AT) gene. The importance of the AR gene appears to be limited but the AT gene might be of considerable importance. It is to be expected that additional breast cancer susceptibility genes will be identified in the near future.
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PMID:Genes responsible for familial breast cancer. 888 Aug 69

Between 5% and 10% of breast cancer cases can be traced to primary genetic factors. Before the discovery of the BRCA1 and BRCA2 genes, if a first-degree relative in direct genetic lineage had hereditary breast cancer or hereditary breast-ovarian cancer syndrome, the best estimate of family members' genetic risk for breast cancer was 50%. Now the lifetime cancer destiny of a patient who carries a BRCA1 or BRCA2 germ line mutation can be determined with an extraordinary degree of precision. However, a major concern facing clinicians is how to use this powerful genetic knowledge without harming the patient. This presentation focuses on the need for (a) compilation of a detailed family history of cancer of all anatomic sites; (b) understanding of the natural history of hereditary breast cancer and its heterogeneous forms and the pathobiology of hereditary breast cancer; and (c) preparation for performance of genetic counseling that is based on the results of DNA sequencing to detect genes related to cancer susceptibility. The discussion addresses the advantages of this molecular genetic movement, which include the abilities (a) to predict who is and who is not at inordinately high risk for cancer; (b) to provide opportunities for highly targeted disease surveillance and management; (c) to give patients the information they need to make appropriate long-term decisions about matters such as procreation; and (d) to give genetic counselors the information they need to appreciate the emotions patients may encounter, such as fear, anxiety, and apprehension, and the ordeal of being subjected to discrimination by insurance companies and employers.
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PMID:Breast cancer genetics: family history, heterogeneity, molecular genetic diagnosis, and genetic counselling. 897 6


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