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Mutations in genes encoding DNA double-strand break (DSB) repair components, especially homologous recombination (HR) proteins, were found to predispose to breast and ovarian cancer. Beyond high penetrance risk gene mutations underlying monogenic defects, low risk gene mutations generate polygenic defects, enlarging the fraction of individuals with a predisposing phenotype. DSB repair dysfunction opens new options for targeted therapies; poly (ADP-ribose) polymerase (PARP) inhibitors have been approved for BRCA-mutated and platinum-responsive ovarian cancers. In this work, we performed functional analyses in peripheral blood lymphocytes (PBLs) using a case-control design. We examined 38 women with familial history of breast and/or ovarian cancer, 40 women with primary ovarian cancer and 34 healthy controls. Using a GFP-based test we analyzed error-prone DSB repair mechanisms which are known to compensate for HR defects and to generate chromosomal instabilities. While non-homologous end-joining (NHEJ) did not discriminate between cases and controls, we found increases of single-strand annealing (SSA) in women with familial risk vs. controls (P=0.016) and patients with ovarian cancer vs. controls (P=0.002). Consistent with compromised HR we also detected increased sensitivities to carboplatin in PBLs from high-risk individuals (P

Background: Risk reducing salpingo-oophorectomy (RRSO) is an effective option to prevent ovarian cancer in high risk women, but side effects related to premature menopause remain a barrier to uptake. Based on data linking the fallopian tube epithelium as the “cells of origin” for ovarian cancer, interval salpingectomy and delayed oophorectomy has been proposed as an alternative to RRSO. Methods: A prospective, multicenter, nonrandomized trial was performed in nine US sites, comparing change in sexual function (primary objective) and other outcomes in high risk women who self-selected ISDO or RRSO. Pre-menopausal women with a documented deleterious mutation in a gene that increased their risk for ovarian cancer were eligible. Baseline, 6 and 12 month questionnaires regarding sexual function, menopausal symptoms, and other outcomes were collected. A safety stopping rule was employed to prevent against unacceptable rate of invasive cancers being detected in the ISDO arm. Findings: Three hundred and seventeen patients completed baseline questionnaires and underwent surgery (RRSO n=147; ISDO n=144). In an age-matched comparison, there was a significantly greater fraction of women who experienced a clinically relevant decrease in sexual function in the RRSO arm compared to ISDO using the total FSFI scale (38% versus 15%, Relative Risk 2.5 (95% CI:1.3-4.8, P

BACKGROUND The clinical relevance of BRCA1/2 alterations in ovarian carcinoma patients is debatable. Our aim was to determine factors influencing the risk of recurrence and death in ovarian carcinoma patients with BRCA pathogenic and unclassified variant mutations. METHODS A consecutive series of 205 women with primary ovarian carcinoma were screened for mutations in BRCA1 and BRCA2 genes using a conformational sensitive gel electrophoresis and direct sequencing. Data regarding medical and familial history were collected using questionnaires. Clinical and pathologic data were extracted from medical records. RESULTS Unclassified variant mutations in BRCA1 or BRCA2 genes were found in 16 (8%) patients, and BRCA1 pathogenic mutations were found in 18 (9%) patients. No pathogenic mutation was found in BRCA2 gene. Multivariate analysis showed that BRCA1 pathogenic mutation was an independent predictor of reduced risk of relapse and death (Hazard ratios [HR] 0.52 [confidence interval {CI} 0.28–0.98] and 0.38 [CI 0.10–0.96], respectively). Unclassified variant mutation did not affect recurrence and survival (HR 0.84 [CI 0.43–1.66] and 0.94 [CI 0.48–1.82], respectively). Other factors associated with reduced risk of relapse and death were complete pathologic remission at second-look laparotomy and family history of breast and ovarian carcinoma, respectively. Recurrence and death outcomes among unclassified variant mutation carriers did not differ significantly from those in sporadic cases. CONCLUSIONS Patients with BRCA1 pathogenic mutation seem to have reduced risk of recurrence and death. These results should be interpreted with caution as they may be influenced by more intensive treatment, better response to cisplatin, and younger age of mutation carriers. Clinical relevance of BRCA1/2 unclassified variant mutations warrants further studies. Cancer 2005. © 2005 American Cancer Society.

Epidemiologic data support the existence of two discrete manifestations of hereditary ovarian carcinoma: the breast and ovarian cancer syndrome and the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome. Genetic linkage analyses reveal that the majority of breast and ovarian cancer families are linked to the BRCA1 gene, while some cases of hereditary ovarian cancer are also apparent in breast cancer families linked to the BRCA2 gene. The majority of HNPCC families are linked to one of four genes encoding a family of DNA mismatch repair proteins. Molecular analyses demonstrate that genetic screening for germline transmission of a defective allele of one or another of these genes is now possible for high-risk individuals. The ethical, legal, and social implications of this type of analysis are multiple and complex, and genetic counseling requires a thorough understanding of these issues and a cautious approach to most effectively meet the special needs of this patient population. Increased medical surveillance and prophylactic oophorectomy are among the management options that may be appropriate for some genetically predisposed, asymptomatic women. Further research is needed regarding the most effective use of this genetic information in formulating counseling and clinical management strategies.

Ovarian carcinoma can be subdivided into two categories termed type I and type II. Type I tumours, usually having an indolent clinical behaviour, are often detected in early stage, and rarely harbour p53 gene mutations. Each histological type has a distinct molecular profile with mutations of genes involved in different signalling transduction pathways, such as KRAS, BRAF, CTNNB1, PTEN, PIK3CA and ARID1A. Type II tumours, accounting for 75% of the cases, have a very aggressive biological behaviour, are usually in advanced stage at presentation, harbour p53 gene mutations in 80% of the cases, and sometimes have alterations of homologous recombination (HR). Both type I and type II tumours arise from extra-ovarian precursors. Serous carcinomas derive from tubal epithelium, endometrioid and clear cell carcinomas from endometrial tissue, and mucinous and Brenner tumours from transitional epithelial cells located near the tubo-peritoneal junction. These new concepts on the pathogenesis of ovarian carcinoma could deeply modify both the preventive approach in women with germ-line BRCA₁ or BRCA₂ mutations and the treatment of patients with advanced or recurrent disease. For instance, BRAF inhibitors could be used in low-grade serous carcinomas, PIK3CA inhibitors could be employed in clear cell carcinoma, and poly (ADP-ribose) polymerase inhibitors could be used not only in hereditary ovarian carcinoma but also in non-hereditary, high-grade serous ovarian carcinoma which sometimes shows defective HR.

Ovarian cancer is the leading cause of death from gynecologic cancer in the united states. Although the etiology of ovarian cancer is unknown, a number of factors including advancing age, nulliparity and environmental factors have traditionally been related to risk. More recently, genetic predisposition has been recognized as a strong risk factor for ovarian cancer. Three distinct hereditary syndromes have been identified: (1) breast-ovarian cancer syndrome, (2) hereditary nonpolyposis colon cancer, and (3) site-specific ovarian cancer. The mode of inheritance in these families is autosomal dominant with transmission occurring through either the maternal or paternal line. The breast-ovarian and site-specific ovarian cancer family syndrome have been linked to a gene on chromosome 17q that is called brca1. However, no simple genetic test can identify women at high risk of the disease. For this reason, genetic counseling, education and surveillance with currently available screening techniques should be made available to women at high risk of ovarian cancer by virtue of their family history. In selected individuals, prophylactic oophorectomy may be warranted. © 1994 Wiley-Liss, Inc.

In the past, hereditary ovarian carcinoma was attributed almost entirely to mutations in BRCA1 and BRCA2, with a much smaller contribution from mutations in DNA mismatch repair genes. Recently, three new ovarian cancer susceptibility genes have been identified: RAD51C, RAD51D, and BRIP1. In addition, germline mutations in women with ovarian carcinoma have been recently identified in many of the previously identified breast cancer genes in the Fanconi anemia (FA)-BRCA pathway. While mutations in genes other than BRCA1 and BRCA2 are each individually rare, together they make up a significant proportion of cases. With at least 16 genes implicated in hereditary ovarian cancer to date, comprehensive testing for ovarian cancer risk will require assessment of many genes. As the cost of genomic sequencing continues to fall, the practice of evaluating cancer susceptibility one gene at a time is rapidly becoming obsolete. New advances in genomic technologies will likely accelerate the discovery of additional cancer susceptibility genes and increase the feasibility of comprehensive evaluation of multiple genes simultaneously at low cost. Improved recognition of inherited risk will identify individuals who are candidates for targeted prevention. In addition, identifying inherited mutations in a variety of FA-BRCA pathway genes may aid in identifying individuals who will selectively benefit from PARP inhibitors.

BACKGROUND: BRCA1 or BRCA2 (BRCA1/2)-mutated ovarian carcinomas may originate in the fallopian tube. The authors of this report investigated alterations in BRCA1/2 tubal epithelium to define the molecular pathogenesis of these carcinomas. METHODS: Tubal epithelium was evaluated from 31 BRCA1/2 mutation carriers with gynecologic carcinomas (BRCA CA), 89 mutation carriers who underwent risk-reducing salpingo-oophorectomy (RRSO), and 87 controls. Ki-67 expression and p53 foci (≥10 of 12 consecutive staining cells) were scored by 2 investigators who were blinded to patient designations. Expression levels of p27 and p21 were evaluated within p53 foci. Loss of heterozygosity at the BRCA1/2 mutation site was evaluated in microdissected p53 foci and tubal neoplasms. RESULTS: Background tubal proliferation as measured by Ki-67 staining was increased in the BRCA1 RRSO group (P = .005) compared with the control group. Women who had BRCA1/2 mutations had more p53 foci identified per tubal segment than women in the control group (P = .02). Levels of p27 were decreased in 12 of 28 p53 foci from women with BRCA1 mutations and in 0 of 16 p53 foci from controls (P = .002). There was no loss of the wild type BRCA1/2 allele in 5 tested p53 foci. Tubal neoplasia lost the wild type allele in 6 of 6 foci (P = .002). CONCLUSIONS: The current results suggested a model of tubal carcinogenesis in women with BRCA1/2 mutations. Increased proliferation occurred globally in at-risk tubal epithelium. A mutation in the tumor protein p53 gene TP53 with clonal proliferation and loss of p27 occurred before neoplastic proliferation. Loss of the wild type BRCA1/2 allele occurred with neoplastic proliferation and before invasion. Cancer 2010. © 2010 American Cancer Society.

No woman is at greater risk for ovarian carcinoma than one who is a member of a hereditary ovarian carcinoma syndrome kindred and whose mother, sister, or daughter has been affected with this disease and with an integrally related hereditary syndrome cancer. This article surveys the existing understanding about hereditary ovarian carcinoma. Emphasis is given to its diagnosis, heterogeneity, interpretation, and the application of this information to improving cancer control.

BRCA2 has been shown to play a significant role in hereditary ovarian carcinoma. Several cases of clear cell carcinoma (CCC) of the ovary containing BRCA2 mutations have been identified. We hypothesize that sequence variants of the BRCA2 gene are common in CCC of the ovary. Multiple methods were utilized to detect BRCA2 genetic alterations in a cohort of 13 ovarian CCC. These included an LOH analysis for copy number, real-time and methylation-specific polymerase chain reaction (PCR) to probe for BRCA2 promoter methylation, in addition to protein truncation testing (PTT) gel screening for nonsense BRCA2 mutations, and finally direct gene sequencing to either confirm the nonsense mutations or to detect candidate missense mutations in the remaining tumor samples. Whenever a sequence variation was detected in a tumor sample, the corresponding region was sequenced from a blood sample to determine germline status. Seven BRCA2 sequence variations were identified in 6 of the 13 CCC (46%); three tumors contained an alteration in BRCA2 copy number. Only one subject carried a germline sequence variation that might alter BRCA2 function despite the fact that a family history of breast, ovarian or colon cancer was common in this population. The 5-year disease-specific survival probability for patients with a BRCA2 alteration is 87.5%, compared to only 40% for those patients without a BRCA2 alteration (p = 0.39). Alterations in BRCA2 gene sequence, copy number, or expression are extremely common in CCC and may contribute to a paradoxical better clinical outcome.

Hereditary ovarian cancer accounts for at least 5% of the estimated 22,000 new cases of this disease during 2009. During this same time, over 15,000 will die from malignancy ascribed to ovarian origin. The bulk of these hereditary cases fits the hereditary breast–ovarian cancer syndrome, while virtually all of the remainder will be consonant with the Lynch syndrome, disorders which are autosomal dominantly inherited. Advances in molecular genetics have led to the identification of BRCA1 and BRCA2 gene mutations which predispose to the hereditary breast–ovarian cancer syndrome, and mutations in mismatch repair genes, the most common of which are MSH2 and MLH1, which predispose to Lynch syndrome. These discoveries enable relatively certain diagnosis, limited only by their variable penetrance, so that identification of mutation carriers through a comprehensive cancer family history might be possible. This paper reviews the subject of hereditary ovarian cancer, with particular attention to its molecular genetic basis, its pathology, and its phenotypic/genotypic heterogeneity.

Hereditary ovarian carcinoma is heterogenous. There are at least three genetic variants, namely, hereditary site-specific ovarian carcinoma, hereditary breast/ovarian carcinoma syndrome, and Lynch syndrome II. Early age of onset characterizes these disorders. A crucial hallmark of these disorders is the integral association of extraovarian cancers, such as carcinoma of the endometrium and colon in Lynch syndrome II. We have described 24 pedigrees of ovarian cancer-prone families in order to depict the several differing heterogenous variants. Interest in hereditary ovarian cancer has increased remarkably, due in part to the fact that its surveillance has been wholly unsatisfactory, as have therapeutic measures. Prevention through prophylactic oophorectomy offers hope. However, there is a risk for extraovarian peritoneal serous papillary carcinoma, consonant with primary cancer of the ovary. This must be discussed with these at-risk patients. Until a biomarker of acceptable sensitivity and specificity is identified, the family history must remain the key to hereditary ovarian cancer diagnosis.

BACKGROUND The objective of this study was to determine the clinical characteristics, treatment response, and frequency of p53 overexpression in Ashkenazi Jewish women with hereditary ovarian carcinoma. METHODS Seventy-one Jewish women with epithelial ovarian carcinoma (EOC) were tested for the three BRCA founder mutations using single-strand conformation polymorphism analysis, heteroduplex analysis, and protein truncation testing. Clinical and histopathologic data were reviewed retrospectively. In vitro chemoresistance was analyzed in 32 patients. Mutations of p53 were studied using immunohistochemical detection of p53 overexpression. RESULTS Thirty-four of 71 Jewish patients with EOC (48%) had germline BRCA mutations (BRCA heterozygotes), including 22 BRCA1 mutations and 12 BRCA2 mutations. BRCA heterozygotes were younger compared with Jewish patients who had EOC without mutations (sporadic carcinoma; 50 years vs. 59 years, respectively; P = 0.01). BRCA1 heterozygotes were younger compared with BRCA2 heterozygotes (48 years vs. 57 years, respectively; P = 0.01). Histopathologic tumor features were similar; however, tumors with low malignant potential were seen only in women with sporadic carcinoma. Both groups had equivalent rates of surgical cytoreduction and similar median follow-up (72 months). BRCA heterozygotes had higher response rates to primary therapy compared with patients who had sporadic disease (P = 0.01). In vitro chemoresistance predicted tumor response to platinum chemotherapy correctly in BRCA heterozygotes (P = 0.0096). BRCA heterozygotes with advance-stage disease had improved survival compared with patients who had advanced stage sporadic carcinoma (91 months vs. 54 months, respectively; P = 0.046) and had a longer disease free interval (49 months vs. 19 months, respectively; P = 0.16). p53 overexpression was common in BRCA heterozygotes (80%). CONCLUSIONS BRCA1 heterozygotes developed EOC at a younger age compared with BRCA2 heterozygotes and women who had sporadic ovarian carcinoma. BRCA heterozygotes had a better response to platinum chemotherapy compared with women who had sporadic disease, which may have contributed to their improved prognosis. Cancer 2003;97:2187–95. © 2003 American Cancer Society. DOI 10.1002/cncr.11310

Ovarian carcinoma is the fourth most common cause of cancer death in women in Western countries. Because of inadequate screening methods and the vague nature of the symptoms, patients present late in the course of the disease and the survival rate is poor. There are no strong environmental risk factors, and after age is controlled for the most important risk factor is a family history of ovarian carcinoma. The effect of a positive family history on a woman's risk of ovarian carcinoma is illustrated in table 1. In this review we focus on the hereditary aspects of ovarian carcinoma. #### Summary points We reviewed original articles and expert reviews from journals cited in Medline between 1980 and 1998 and supplemented this information with unpublished data from our colleagues. We also included information from recently published books. In performing the Medline searches we used the following key words: hereditary ovarian carcinoma, breast and ovarian carcinoma syndrome, ovarian cancer screening, prophylactic oophorectomy. Between 5% and 10% of cases of ovarian carcinoma are the result of an inherited gene or genes. The percentage depends on the degree of relatives included in the calculation and the method of case ascertainment.2 Narod et al …

Ovarian cancer is the fifth most common malignancy among North American women and the fourth leading cause of cancer death. Approximately 5 to 13% of all ovarian cancer cases are caused by the inheritance of cancer predisposing genes with an autosomal pattern of transmission.1 Hereditary ovarian carcinoma has been described in association with mutations in four genes, BRCA1 , BRCA2 , MLH1 , and MSH2 , although usually ovarian carcinoma (OC) does not occur in a site specific fashion, but is associated with breast cancer ( BRCA1 and BRCA2 ) or colorectal and endometrial cancer ( MLH1 and MSH2 ). The large majority of hereditary OC is attributable to mutations in BRCA1. While mutations in BRCA1 have been seen in large pedigrees with apparently site specific OC predisposition,2 mutations in BRCA2 that have been associated with site specific OC are rare, and have often been missense mutations.3,4 The biological significance of such mutations can be uncertain. Gayther et al 5 reported that mutations in a 3.3 kb segment of exon 11 of BRCA2 were associated with a higher risk of OC relative to breast cancer than were mutations outside this region (p = 0.0004). They called this region of BRCA2 the ovarian cancer cluster region (OCCR). In an expanded study from the same group, Thompson et al 6 estimated that mutations in the ovarian cancer cluster region (OCCR) of BRCA2 are associated with an OC risk to the age of 70 of 19.5% (95% confidence interval (CI) 11.6 to 31.7), whereas the equivalent risk associated with mutations outside this region has been estimated at 10.9% (95% CI 5.5 to 20.9). Despite the concluding comments of the authors, urging a cautious interpretation of their data, if these estimates were to be used to counsel women who carry BRCA2 mutations, those who …

Three ovarian-cancer-prone kindreds were studied, two of which contained identical twin sisters concordant for ovarian carcinoma. In one kindred, both identical twin sisters had daughters with ovarian carcinoma. In another kindred, one of the identical twin sisters had an ovarian-cancer-affected daughter. Ovarian carcinoma showed vertical transmission in all three families in a pattern consonant with an autosomal dominant mode of inheritance. Medical-genetic survey of each family included detailed questionnaires with retrieval of primary medical and pathology documents on cancer of all anatomic sites. Putative biomarker determinations included: (1) in vitro hyperdiploidy in dermal monolayer cultures; and (2) lower serum levels of alpha-L-fucosidase (less than or equal to 275 IU/ml) in all cancer-affected patients and statistically significant lower levels in 50% risk individuals when compared to spouse and published controls (P = 0.04 and P = 0.0002, respectively). These findings are discussed in context with the eventual development of a risk factor profile which, given acceptable sensitivity and specificity, would enable identification of individuals who would be prime candidates for intensive surveillance/management programs.