Comparison of Clinical Outcomes of BRCA1/2 Pathologic Mutation, Variants of Unknown Significance, or Wild Type Epithelial Ovarian Cancer Patients

Impact of molecular testing on the surgical management of advanced epithelial ovarian cancer

Ovarian carcinoma remains the most lethal gynaecologic malignancy. Half of all high-grade serous ovarian cancers (HGSOCs) have a homologous recombination deficiency (HRD) with regard to the repair of double-strand DNA breaks and are candidate to receive maintenance treatment with PARP inhibitors. While a wealth of literature exists regarding the therapeutic guidance of patients from a medical standpoint, the influence of the HRD status on the surgical outlook has been comparatively limited. In this review, the clinical and biological features of advanced ovarian cancers with BRCA1/2 mutation and/or HRD status are considered with particular reference to their impact on the surgical management and on the medico-surgical sequence. The modification of the surgical indications according to the results of molecular testing in first-line and recurrent settings are discussed.

Modeling human cancer predisposition syndromes using CRISPR/Cas9 in human cell line models

The advancement of CRISPR mediated gene engineering provides an opportunity to improve upon preclinical human cell line models of cancer predisposing syndromes. This review focuses on using CRISPR/Cas9 genome editing tools to model various human cancer predisposition syndromes. We examine the genetic mutations associated with neurofibromatosis type 1, Li-Fraumeni syndrome, Gorlin syndrome, BRCA mutant breast and ovarian cancers, and APC mutant cancers. Furthermore, we discuss the possibilities of using next-generation CRISPR-derived precision gene editing tools to introduce a variety of genetic lesions into human cell lines. The goal is to improve the quality of preclinical models surrounding these cancer predisposition syndromes through dissecting the effects of these mutations on the development of cancer and to provide new insights into the underlying mechanisms of these cancer predisposition syndromes. These studies demonstrate the continued utility and improvement of CRISPR/Cas9-induced human cell line models in studying the genetic basis of cancer.

Factors predicting BRCA1/2 pathogenic variants in patients with ovarian cancer: a systematic review with meta-analysis

AIM

To provide accurate figures of the frequency of specific clinical features in ovarian cancer (OC) associated with germline BRCA1/2 pathogenic variants and to define their relevance in predicting the presence of a germline pathogenic variant in these genes.

METHODS

A systematic review of papers published from 1995 to February 2022 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data from eligible papers were synthesised through meta-analysis.

RESULTS

Thirty-seven papers were reviewed, including a total of 12 886 patients with OC. Among BRCA carriers, 86.4% displayed serous type, 83.3% high grade (G3), 83.7% FIGO (The International Federation of Gynecology and Obstetrics) stage III/IV, 39.7% age at diagnosis ≤50 years and 18.1% personal breast cancer history, while the frequency of these features in non-carriers resulted significantly lower (p<0.001). The meta-analysis showed that the strongest predictor of BRCA1/2 pathogenic variants was a personal breast cancer history (OR 5.21, 95% CI 4.02 to 6.55, compared with no previous breast cancer), followed by high grade (OR 2.47, 95% CI 1.97 to 3.10, compared with low/intermediate grade), serous histotype (OR 2.33, 95% CI 2.07 to 2.64, compared with other histotypes), advanced (III/IV) FIGO stage (OR 1.89, 95% CI 1.67 to 2.15, compared with stage I/II) and age at diagnosis ≤50 years (OR 1.20, 95% CI 1.01 to 1.42, compared with >50 years).

CONCLUSION

The results of this meta-analysis provide data on features increasing the prior probability of finding BRCA1/2 pathogenic variants that may prove helpful in counselling patients and prioritising testing.

PROSPERO REGISTRATION NUMBER

CRD42021271815.

Survival outcomes in patients with BRCA mutated, variant of unknown significance, and wild type ovarian cancer treated with PARP inhibitors

OBJECTIVE

Correlation between BRCA1/2 (BRCA) pathogenic variants and the response to poly (ADP-ribose) polymerase inhibitors (PARPi) has been recognized in patients with ovarian cancer. Moreover, data on the clinical implications of variants of unknown significance are lacking. The aim of this study was to evaluate differences in survival outcomes in patients with BRCA variants of unknown significance, mutated, and wild type relapsed ovarian cancer treated with PARPi.

METHODS

Patients with ovarian cancer whose somatic BRCA testing was available and who were receiving PARPi as maintenance treatment at the first recurrence between January 2014 and January 2021 were included in the present study and analyzed. Patients were divided into three groups according to BRCA mutational status (variant of unknown significance, mutated, and wild type). Progression-free survival was assessed in each study group.

RESULTS

Of 67 patients identified, 20 (29.9%), 24 (35.8%), and 23 (34.3%) had BRCA variant of unknown significance, mutated, and wild type, respectively. Patients received PARPi as maintenance treatment at the time of the first relapse after a complete response or partial response to platinum-based chemotherapy without differences in the previous platinum-free interval among the analyzed groups. The median progression-free survival of patients with BRCA mutation was significantly longer than for those with BRCA wild type or variant of unknown significance (not reached vs 4 months vs 7 months, respectively; p<0.001). Additionally, no significant difference was found between patients with BRCA wild type and BRCA variant of unknown significance (p=0.50).

CONCLUSION

Our study suggests that carriers of BRCA variant of unknown significance have survival outcomes comparable to patients with BRCA wild type and shorter progression-free survival than women harboring BRCA pathogenic variants.

Mutations in Homologous Recombination Genes and Loss of Heterozygosity Status in Advanced-Stage Breast Carcinoma

Poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPis) have demonstrated antitumor activity in cancers with a homologous recombination deficiency (HRD) and have recently been approved by the FDA for the treatment of germline BRCA1/2-mutation-associated breast cancer. PARPis have also been found to be efficacious in BRCA wild-type (BRCAwt) lesions with high genomic loss of heterozygosity (LOH-high). The goal of this study was to retrospectively investigate the tumor mutations in homologous recombination (HRR) genes and the LOH score in advanced-stage breast carcinomas (BCs). Sixty-three patients were included in our study, 25% of whom had HRR gene mutations in their tumors, including 6% BRCA1/2 and 19% non-BRCA-containing gene mutations. An HRR gene mutation was associated with a triple-negative phenotype. Twenty-eight percent of the patients had an LOH-high score, which, in turn, was associated with a high histological grade, a triple-negative phenotype, and a high tumor mutational burden (TMB). Among the six patients who received PARPi therapy, one had a tumor with a PALB2 mutation other than BRCA and had a clinical partial response. Twenty-two percent of the LOH-low tumors had BRCAwt-HRR gene mutations, compared with 11% of the LOH-high tumors. Comprehensive genomic profiling revealed a subset of breast cancer patients with a BRCAwt-HRR gene mutation that would be missed by an LOH test. The necessity of next-generation sequencing coupled with HRR gene analysis for PARPi therapy requires further investigation in clinical trials.

The expression and mutation of BRCA1/2 genes in ovarian cancer: a global systematic study

INTRODUCTION

This systematic review was designed to summarize the findings on expression and mutation of BRCA1/2 genes in ovarian cancer (OC) patients, focusing on mutation detection technology and taking clinical decisions for better treatment.

AREAS COVERED

We conducted a systematic review by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses document selection guidelines for the document selection process and the PICOT standard for developing the keywords to search for. A total of 5729 publications were included, and 50 articles were put into the final screening. The results showed that Next-Generation Sequencing was a breakthrough technology in detecting Breast Cancer 1/2 (BRCA1/2) gene mutations because of its efficacy and affordability. Other technologies are also being applied now for mutation detection. The most prominent associations of BRCA1/2 gene mutations were age, heredity, and family history. Furthermore, mutations of BRCA1/2 could improve survival rate and overall survival. There is no sufficient study available to conclude a systematic analysis for the expression of BRCA1/2 gene in OC.

EXPERT OPINION

Research will continue to develop more diagnostic techniques based on the expression and mutation of BCRA1/2 genes for OC in the near future.

Implementation of Comprehensive Genomic Profiling in Ovarian Cancer Patients: A Retrospective Analysis

Comprehensive genomic profiling (CGP) allows for the detection of driver alterations at high resolution, but the limited number of approved targeted therapies and their high costs have contributed to its limited clinical utilization. We retrospectively compared data of 946 women with ovarian cancer (11.4% were referred to CGP, and 88.6% served as control) to examine whether CGP provides a prognosis benefit. Patient baseline parameters were similar between the groups. Cox regression analysis adjusted for age, disease stage at diagnosis, and recurrence status showed statistically significantly longer median overall survival (mOS) in the CGP group versus the control (73.4 versus 54.5 months, p < 0.001). Fifty-four patients (52.9%) had actionable mutations with potential treatments; twenty-six (48.2%) were treated with matched targeted therapy, showing a trend for longer mOS than the eighty-six women in the CGP group who were not given a suggested treatment (105.5 versus 63.6 months, p = 0.066). None of the genomic alterations predicted metastasis location. CCNE1 amplification and KRAS mutations were associated with shorter mOS. Patients with tumor mutation burden ≥4 mutations/megabase had longer mOS. High loss of heterozygosity was associated with longer mOS (99.0 versus 48.2 months, p = 0.004). CGP testing may provide both prognostic and predictive insights for treatment of patients with ovarian cancer. Prospective studies of larger cohorts are warranted.

Clinical Impact of Next-Generation Sequencing Multi-Gene Panel Highlighting the Landscape of Germline Alterations in Ovarian Cancer Patients

BRCA1 and BRCA2 are the most frequently mutated genes in ovarian cancer (OC) crucial both for the identification of cancer predisposition and therapeutic choices. However, germline variants in other genes could be involved in OC susceptibility. We characterized OC patients to detect mutations in genes other than BRCA1/2 that could be associated with a high risk of developing OC and permit patients to enter the most appropriate treatment and surveillance program. Next-generation sequencing analysis with a 94-gene panel was performed on germline DNA of 219 OC patients. We identified 34 pathogenic/likely pathogenic variants in BRCA1/2 and 38 in other 21 genes. The patients with pathogenic/likely pathogenic variants in the non-BRCA1/2 genes mainly developed OC alone compared to the other groups that also developed breast cancer or other tumors (p = 0.001). Clinical correlation analysis showed that the low-risk patients were significantly associated with platinum sensitivity (p < 0.001). Regarding PARP inhibitors (PARPi) response, the patients with pathogenic mutations in the non-BRCA1/2 genes had worse PFS and OS. Moreover, a statistically significantly worse PFS was found for every increase of one thousand platelets before PARPi treatment. To conclude, knowledge about molecular alterations in genes beyond BRCA1/2 in OC could allow for more personalized diagnostic, predictive, prognostic, and therapeutic strategies for OC patients.

Association of BRCA1/2 mutations with prognosis and surgical cytoreduction outcomes in ovarian cancer patients: An updated meta-analysis

AIM

This meta-analysis was conducted to evaluate the impact of BRCA mutations on survival outcomes of ovarian cancer patients and assess whether the BRCA status was an independent predictor of complete cytoreduction.

METHODS

We searched the PubMed, Cochrane, EMBASE, Scopus, Web of Science, and Google Scholar databases for studies that evaluated the associations among BRCA mutations, ovarian cancer survival and surgical cytoreduction before August 2021 based on specific inclusion and exclusion criteria.

RESULTS

We identified 61 articles that compared the clinical features, survival outcomes, and optimal surgical cytoreduction rates between BRCA-positive patients and BRCA-negative patients. The results showed that BRCA mutation carriers were diagnosed with ovarian cancer at a younger age than the age at which nonmutation carriers were diagnosed. In addition, BRCA mutation carriers were more likely to be in the International Federation of Gynecology and Obstetrics (FIGO) stage III-IV, and the pathological grade was commonly grade 3. The pathological type of BRCA mutation carriers was more likely to be high-grade serous carcinoma. Patients with BRCA mutations had higher response rates to platinum-based chemotherapy than the noncarriers. However, patients in both groups had equivalent rates of surgical cytoreduction, and BRCA-positive patients had longer overall survival (OS) time (HR = 0.65; 95% confidence interval [CI]: 0.59, 0.73; p < 0.001) and longer progression-free survival (PFS) (HR = 0.72; 95% CI: 0.63, 0.82; p < 0.001).

CONCLUSION

BRCA mutations appear to be associated with improved OS and PFS in patients with ovarian cancer. However, we did not find any difference in the surgical resection rate between participants in the two groups.

Recurrent Ovarian Cancer with BRCAness Phenotype: A Treatment Challenge

INTRODUCTION

Ovarian cancer is a leading cause of death among women with gynecologic malignancies. The relapse rate is high after platinum-based therapy, with the effectiveness of subsequent treatment lines decreasing over time. Recent data suggest the benefit of maintenance therapy with niraparib in platinum-sensitive recurrent disease.

CASE PRESENTATIONS

We report a case series of five women with advanced ovarian cancer and BRCAness phenotype who responded favorably, and in some cases with long-term response, to maintenance therapy with niraparib. Toxicities were as expected and generally manageable. Two patients developed grade 2/3 hematological toxicity, which resolved with treatment suspension and subsequent dose reductions, and one patient reported a rare skin toxicity while responding to full-dose niraparib treatment, which was controlled with photoprotection and sunscreen.

DISCUSSION AND CONCLUSIONS

This case series highlights the role of PARP1/2 inhibitors as a new standard of care as maintenance therapy for recurrent platinum-sensitive high-grade ovarian cancer, irrespective of BRCA status.

Reclassification of BRCA1 and BRCA2 variants found in ovarian epithelial, fallopian tube, and primary peritoneal cancers

Objective

We investigated the proportions of and reclassified BRCA1/2 variants of unknown significance (VUS) in Korean patients with epithelial ovarian, tubal, and primary peritoneal cancers.

Methods

Data from 805 patients who underwent genetic testing for BRCA1/2 from January 1, 2006 to August 31, 2018 were included. The VUS in BRCA1/2 were reclassified using the 2015 American College of Medical Genetics and Genomics and the Association for Molecular Pathology standards and guidelines.

Results

A BRCA1 pathogenic variant was found in 17.0% (137/805) of the patients, and BRCA1 VUS were found in 15.9% (128/805) of the patients. Further, 8.7% (69/805) of the patients possessed a BRCA2 pathogenic variant and 18.4% (148/805) of the patients possessed BRCA2 VUS. Fifty-three specific BRCA1 VUS were found and 20 were further reclassified as benign (n=11), likely benign (n=5), likely pathogenic (n=3), and pathogenic (n=1). The remaining 33 remained classified as VUS. For BRCA2, 55 specific VUS were detected; among these, 14 were reclassified as benign or likely benign, and 2 were reclassified as likely pathogenic. Among the 805 patients, 195 were found to have only VUS and no pathogenic variants (PV), and 41.5% (81/195) were reclassified as benign or likely benign, and 10.3% (20/195) as pathogenic or likely pathogenic variants.

Conclusions

Approximately 33.3% (36/108) of the specific BRCA1/2 variants analyzed in this study that were initially classified as VUS over a 13-year period were reclassified. Among these, 5.6% (6/108) were reclassified as pathogenic or likely pathogenic variants.

Current update on malignant epithelial ovarian tumors

Epithelial ovarian cancer (EOC) represents the most frequently occurring gynecological malignancy, accounting for more than 70% of ovarian cancer deaths. Preoperative imaging plays an important role in assessing the extent of disease and guides the next step in surgical decision-making and operative planning. In this article, we will review the multimodality imaging features of various subtypes of EOC. We will also discuss the role of imaging in the staging, management, and surveillance of EOC.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

Association of Germline Variants in Human DNA Damage Repair Genes and Response to Adjuvant Chemotherapy in Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND

The frequency and significance of the germline variants in DNA damage repair genes still need to be elucidated in patients with sporadic pancreatic ductal adenocarcinoma (PDAC). Our purpose was to determine whether germline variants in DNA damage repair genes were associated with survival of patients with sporadic PDAC.

STUDY DESIGN

We retrospectively identified 854 patients with sporadic PDAC with germline DNA sequenced in targeted 22 DNA damage repair genes by next-generation sequencing. Outcomes were compared in terms of clinicopathologic features, disease-free survival (DFS), and overall survival (OS).

RESULTS

Nineteen patients had deleterious mutations; 103 had variant(s) of unknown significance (VUS). Germline DNA damage repair deleterious variant carriers had superior DFS (median, 19.1 months vs 11.9 months, p = 0.012) and OS (median, 29.7 months vs 20.2 months, p = 0.034), as compared with wild-type patients. Germline DNA damage repair VUS variant carriers also had superior DFS when compared with wild-type patients. In subgroup analysis, this improved survival was limited to patients receiving adjuvant chemotherapy, deleterious variant carriers vs wild-type patients DFS (median 36.3 months vs 13.1 months, p = 0.006) and OS (median 43.7 months vs 24.3 months, p = 0.045), VUS variant carriers vs wild-type patients DFS (16.5 months vs 13.1 months, p = 0.007).

CONCLUSIONS

Having a deleterious variant in a DNA damage repair gene is associated with improved survival after resection and adjuvant chemotherapy for pancreatic ductal adenocarcinoma.

Mutation landscape of germline and somatic BRCA1/2 in patients with high-grade serous ovarian cancer

Background

Poly (ADP-ribose) polymerase inhibitors targeting BRCA1/2 mutations are available for treating patients with high-grade serous ovarian cancer. These treatments may be more appropriately directed to patients who might respond if the tumor tissue is additionally tested by next-generation sequencing with a multi-gene panel and Sanger sequencing of a blood sample. In this study, we compared the results obtained using the next-generation sequencing multi-gene panel to a known germline BRCA1/2 mutational state determined by conventional Sanger sequencing to evaluate the landscape of somatic mutations in high-grade serous ovarian cancer tumors.

Methods

Cancer tissue from 98 patients with high-grade serous ovarian cancer who underwent Sanger sequencing for germline BRCA1/2 analysis were consecutively analyzed for somatic mutations using a next-generation sequencing 170-gene panel.

Results

Twenty-four patients (24.5%) showed overall BRCA1/2 mutations. Seven patients (7.1%) contained only somatic BRCA1/2 mutations with wild-type germline BRCA1/2, indicating acquired mutation of BRCA1/2. Three patients (3.1%) showed reversion of germline BRCA1 mutations. Among the 14 patients (14.3%) with both germline and somatic mutations in BRCA1/2, two patients showed different variations of BRCA1/2 mutations. The next-generation sequencing panel test for somatic mutation detected other pathogenic variations including RAD51D and ARID1A, which are possible targets of poly (ADP-ribose) polymerase inhibitors. Compared to conventional Sanger sequencing alone, next-generation sequencing-based tissue analysis increased the number of candidates for poly (ADP-ribose) polymerase inhibitor treatment from 17.3% (17/98) to 26.5% (26/98).

Conclusions

Somatic mutation analysis by next-generation sequencing, in addition to germline BRCA1/2 mutation analysis, should become the standard of care for managing women with high-grade serous ovarian cancer to widen the indication of poly (ADP-ribose) polymerase inhibitors.

Prevalence and oncologic outcomes of BRCA1/2 mutation and variant of unknown significance in epithelial ovarian carcinoma patients in Korea

Objective

BRCA mutational status is important in the management of ovarian cancer, but there is a lack of evidence supporting genetic testing in Asian populations. This study was performed to investigate the prevalence and prognostic outcomes of BRCA1/2 mutation and variant of unknown significance (VUS) in Korean patients diagnosed with epithelial ovarian cancer (EOC).

Methods

Among patients newly diagnosed with EOC between January 2007 and January 2017, those tested for germline BRCA1/2 mutation were studied, regardless of family history. Overall survival (OS) and progression-free survival (PFS) were compared between the patients with and without BRCA1/2 mutation and VUS.

Results

A total of 313 patients underwent BRCA testing: 88 patients had a BRCA1/2 mutation and 48 patients had a BRCA1/2 VUS (28.1% and 15.3%, respectively). There were no significant associations between BRCA1/2 mutation, BRCA1/2 wild-type, or BRCA1/2 VUS with age at diagnosis, histologic distribution, or residual disease status after primary cytoreductive surgery. BRCA1 mutation, including BRCA1 VUS, showed no difference in PFS or OS compared to BRCA1 wild-type. In contrast, BRCA2 mutation showed longer PFS than that of BRCA2 wild-type (P=0.04) or BRCA2 VUS (P=0.02). BRCA2 mutation, including BRCA2 VUS, did not show any difference in OS compared to BRCA2 wild-type.

Conclusion

BRCA mutation and BRCA VUS had similar clinical characteristics and survival outcomes, except that BRCA2 mutation showed better PFS. The results of this study will help to understand the prognostic significance of BRCA mutation and VUS in Korean patients.

The BRCA1 Methylation and PD-L1 Expression in Sporadic Ovarian Cancer

Objective

This study aimed to assess the relationship between BRCA1 gene methylation, PD-L1 protein expression, and the clinicopathologic features of sporadic ovarian cancer (OC).

Methods

Bisulfite pyrosequencing and immunohistochemistry were used to detect BRCA1 gene methylation and PD-L1 protein expression, respectively, in tumor tissues from 112 patients with sporadic OC. Their levels were analyzed against clinicopathologic characteristics and prognosis using standard statistical methods.

Results

Twenty percent (22/112) of the OC cases exhibited BRCA1 gene hypermethylation. The frequency of BRCA1 hypermethylation was significantly higher in serous OC (25%) than in nonserous OC (8%; P < 0.05). No significant correlations were discovered between BRCA1 hypermethylation and age, menstrual status, tumor location, stage, lymph node metastasis, and prognosis (P > 0.05). Among the 112 OC cases, 59% (66/112) cases were positive for PD-L1 protein expression. No significant difference existed between PD-L1 expression and age, menstrual status, histological type, tumor location, stage, lymph node metastasis, and prognosis (P > 0.05). Moreover, no correlation existed between BRCA1 methylation and PD-L1 expression (P > 0.05, r = 0.002).

Conclusions

This is the first study linking BRCA1 hypermethylation variability to PD-L1 protein expression and the clinicopathologic features of OC. The data demonstrated that an epigenetic alteration of BRCA1 was closely associated with serous OC. The expression of PD-L1 was unrelated to the clinicopathologic features or BRCA1 hypermethylation in sporadic OC.

Clinical and Genetic Characteristics of BRCA1/2 Mutation in Korean Ovarian Cancer Patients: A Multicenter Study and Literature Review

PURPOSE

We investigated the clinical relevance and spectrum of BRCA1/2 mutations in Korean ovarian cancer (KoOC) patients.

MATERIALS AND METHODS

Two hundred seventy-nine KoOC patients were enrolled from three university hospitals between 2012 and 2017. Their peripheral blood samples were obtained for BRCA1/2 mutation analysis by direct sequencing. Clinicopathological characteristics were retrospectively reviewed, and spectrum analyses of BRCA1/2 mutation were assessed by systematic literature review.

RESULTS

Frequency of BRCA1/2 mutations was 16.5% in KoOC patients. BRCA1/2 mutations were significantly associated with family history of breast/ovarian cancer (p<0.001), serous histology (p=0.044), and advanced International Federation of Gynecology and Obstetrics (FIGO) stage (III/IV, p=0.018) but not with early age-of-onset (age < 50, p=0.729). Literature review of BRCA1/2 mutations in KoOC patients found 111 (55 distinct) mutations with high proportion of Korean-specific mutations (24/55, 43.6%). Comparing the spectrum of BRCA1/2 mutation between KoOC and Korean breast cancer (KoBC) patients, the ratio of BRCA1-to-BRCA2 mutations was different, with BRCA1 (78.4%) being predominant in KoOC and BRCA2 in KoBC (59.2%). The most common mutation also differed between the two (c.3627insA of BRCA1 in KoOC and c.7480C>T of BRCA2 in KoBC).

CONCLUSION

The clinical relevance of BRCA1/2 mutations in KoOC patients was confirmed but that of early age-of-onset was not. Possible inconsistency in the ratio of BRCA1-to-BRCA2 mutations and the most common mutation between KoOC and KoBC may probably suggest presence of mutation sequence-associated penetrance tendency in hereditary Korean breast and ovarian cancer. These data may provide insights for optimal genetic counseling and prophylactic treatment for at-risk relatives of KoOC patients.

DNA damage response and repair in ovarian cancer: Potential targets for therapeutic strategies

Ovarian cancer is among the most lethal gynecologic malignancies with a poor survival prognosis. The current therapeutic strategies involve surgery and chemotherapy. Research is now focused on novel agents especially those targeting DNA damage response (DDR) pathways. Understanding the DDR process in ovarian cancer necessitates having a detailed knowledge on a series of signaling mediators at the cellular and molecular levels. The complexity of the DDR process in ovarian cancer and how this process works in metastatic conditions is comprehensively reviewed. For evaluating the efficacy of therapeutic agents targeting DNA damage in ovarian cancer, we will discuss the components of this system including DDR sensors, DDR transducers, DDR mediators, and DDR effectors. The constituent pathways include DNA repair machinery, cell cycle checkpoints, and apoptotic pathways. We also will assess the potential of active mediators involved in the DDR process such as therapeutic and prognostic candidates that may facilitate future studies.

Effect of BRCA mutational status on survival outcome in advanced-stage high-grade serous ovarian cancer

Objective

To evaluate impact of germline BRCA mutational status on prognosis in patients with advanced ovarian cancer.

Methods

A total of 128 patients diagnosed with FIGO stage III-IV high-grade serous ovarian cancer (HGSOC) between 2008 and 2017 and underwent BRCA1/2 gene testing at the time of or within two years from cancer diagnosis were included in this study. We compared patients’ clinicopathological characteristics and survival outcomes after primary treatment according to germline BRCA mutational status. Treatment-related factors that might affect patients’ survival outcome were also investigated.

Results

Germline BRCA1/2 mutations were observed in 51 women (39.8%). There were no differences in age and serum CA-125 levels at the time of HGSOC diagnosis, use of neoadjuvant chemotherapy (NAC), extent of debulking surgery, and overall survival (OS) between the BRCA mutation and wild-type BRCA groups. In contrast, the BRCA mutation group displayed longer progression-free survival (PFS) (median, 22.9 vs. 16.9 months, P = 0.001). Multivariate analyses identified germline BRCA1/2 mutation as an independent favorable prognostic factor for PFS (adjusted HR, 0.502; 95% CI, 0.318–0.795; P = 0.003). In the wild-type BRCA group, patients who received NAC as the primary treatment had shorter PFS compared to those who received primary debulking surgery (PDS) (median, 14.2 vs. 16.9 months, P = 0.003). However, in the BRCA mutation group, PFS did not differ between the NAC and PDS groups (P = 0.082).

Conclusions

In advanced-stage HGSOC, patients with germline BRCA1/2 mutations have better prognosis with longer PFS than those lacking BRCA mutations. Prognosis after NAC was different according to the BRCA mutational status.

Electronic supplementary material

The online version of this article (10.1186/s13048-019-0511-7) contains supplementary material, which is available to authorized users.

Selecting variants of unknown significance through network-based gene-association significantly improves risk prediction for disease-control cohorts

Variants of unknown/uncertain significance (VUS) pose a huge dilemma in current genetic variation screening methods and genetic counselling. Driven by methods of next generation sequencing (NGS) such as whole exome sequencing (WES), a plethora of VUS are being detected in research laboratories as well as in the health sector. Motivated by this overabundance of VUS, we propose a novel computational methodology, termed VariantClassifier (VarClass), which utilizes gene-association networks and polygenic risk prediction models to shed light into this grey area of genetic variation in association with disease. VarClass has been evaluated using numerous validation steps and proves to be very successful in assigning significance to VUS in association with specific diseases of interest. Notably, using VUS that are deemed significant by VarClass, we improved risk prediction accuracy in four large case-studies involving disease-control cohorts from GWAS as well as WES, when compared to traditional odds ratio analysis. Biological interpretation of selected high scoring VUS revealed interesting biological themes relevant to the diseases under investigation. VarClass is available as a standalone tool for large-scale data analyses, as well as a web-server with additional functionalities through a user-friendly graphical interface.

Detection of Germline Mutations in Patients with Epithelial Ovarian Cancer Using Multi-gene Panels: Beyond BRCA1/2

PURPOSE

Next-generation sequencing (NGS) allows simultaneous sequencing of multiple cancer susceptibility genes and may represent a more efficient and less expensive approach than sequential testing. We assessed the frequency of germline mutations in individuals with epithelial ovarian cancer (EOC), using multi-gene panels and NGS.

MATERIALS AND METHODS

Patients with EOC (n=117) with/without a family history of breast or ovarian cancer were recruited consecutively, from March 2016 toDecember 2016.GermlineDNAwas sequenced using 35-gene NGS panel, in order to identify mutations. Upon the detection of a genetic alteration using the panel, results were cross-validated using direct sequencing.

RESULTS

Thirty-eight patients (32.5%) had 39 pathogenic or likely pathogenic mutations in eight genes, including BRCA1 (n=21), BRCA2 (n=10), BRIP1 (n=1), CHEK2 (n=2), MSH2 (n=1), POLE (n=1), RAD51C (n=2), and RAD51D (n=2). Among 64 patients with a family history of cancer, 27 (42.2%) had 27 pathogenic or likely pathogenic mutations, and six (9.3%) had mutations in genes other than BRCA1/2, such as CHECK2, MSH2, POLE, and RAD51C. Fifty-five patients (47.0%) were identified to carry only variants of uncertain significance.

CONCLUSION

Using the multi-gene panel test, we found that, of all patients included in our study, 32.5% had germline cancer-predisposing mutations. NGS was confirmed to substantially improve the detection rates of a wide spectrum of mutations in EOC patients compared with those obtained with the BRCA1/2 testing alone.

Prevalence of germline BRCA mutations among women with carcinoma of the peritoneum or fallopian tube

Objective

The aim of the present study was to assess the frequency of germline mutations in patients with peritoneal carcinoma (PC) or the fallopian tube carcinoma (FTC), using a multi-gene panel.

Methods

Twenty-six patients diagnosed with either PC or FTC between January 2013 and December 2016 were recruited consecutively. Germline DNA was sequenced using a 6-gene next generation sequencing (NGS) panel following genetic counseling. Surgico-medical information was obtained from hospital records. Genetic variations were detected using the panel and were cross-validated by Sanger direct sequencing.

Results

Germline BRCA1/2 mutations were identified in 6 patients (23.1%). Four were detected in patients with PC and 2 were in FTC patients. No mutations were detected in TP53, PTEN, CDH1, or PALB2. We identified 11 variant of uncertain significance (VUS) in 9 patients; 2 in BRCA1, 3 in BRCA2, 2 in TP53, and 4 in CDH1. We also detected a CDH1 c.2164+16->A VUS in 3 patients.

Conclusion

The prevalence of germline BRCA1/2 mutations in patients with PC or FTC is comparable to that of BRCA1/2 mutations in epithelial ovarian cancer patients.

Unclassified Variants of BRCA1 and BRCA2 in Korean Patients With Ovarian Cancer

OBJECTIVE

The aim of the present study was to investigate unclassified variants (UVs) in BRCA1 and 2 of Korean patients with ovarian cancer.

METHODS

We retrospectively analyzed 138 patients diagnosed with ovarian/fallopian tubal/peritoneal cancer between January 2013 and January 2016, whose BRCA genetic test results and clinical characteristics were available for review. Patient peripheral blood lymphocyte specimens were assessed for BRCA mutations and variations by direct sequencing. Identified UVs were classified according to several algorithms.

RESULTS

The results of genetic testing revealed 31 (22.5%, 31/138) pathogenic BRCA mutations (24 BRCA1, 7 BRCA2 mutations). The BRCA1 c.390C>A mutation was observed in 4 patients (12.9%, 4/31). Thirty-four (24.6%, 34/138) BRCA UVs were identified in 33 patients. Of these, the BRCA1 c.4883T>C and BRCA2 c.8187G>T variants were each detected in 4 patients (4/34, 11.8%). According to the used algorithms and cosegregation test, the BRCA1 c.5339T>C and BRCA2 c.8437_8439delGGA variants were both predicted to be likely pathogenic.

CONCLUSIONS

The 2 identified likely pathogenic UVs require further verification with clinical evidence. Clarifying the clinical significance of UVs is an increasingly important step for cancer treatment in the current era of precision medicine.