Evaluation of Homologous Recombination Deficiency in Ovarian Cancer.

OPINION STATEMENT: Homologous recombination deficiency (HRD) is an important biomarker guiding selection of ovarian cancer patients who will derive the most benefit from poly(ADP-ribose) polymerase inhibitors (PARPi). HRD prevents cells from repairing double-stranded DNA damage with high fidelity, PARPis limit single-stranded repair, and together these deficits induce synthetic lethality. Germline or somatic BRCA mutations represent the narrowest definition of HRD, but do not reflect all patients who will have a durable PARPi response. HRD can also be defined by its downstream consequences, which are measured by different metrics depending on the test used. Ideally, all patients will undergo genetic counseling and germline testing shortly after diagnosis and have somatic testing sent once an adequate tumor sample is available. Should barriers to one test be higher, pursuing germline testing with reflex to somatic testing for BRCA wildtype patients or somatic testing first strategies are both evidence-based. Ultimately both tests offer complementary information, germline testing should be pursued for any patient with a history of ovarian cancer, and somatic testing is valuable at recurrence if not performed in the upfront setting. There is a paucity of data to suggest superiority of one germline or somatic assay; therefore, selection should optimize turnaround time, cost to patients, preferred result format, and logistical burden. Each clinic should implement a standard testing strategy for all ovarian cancer patients that ensures HRD status is known at the time of upfront chemotherapy completion to facilitate comprehensive counseling about anticipated maintenance PARPi benefit.

CA125 Levels in BRCA mutation carriers - a retrospective single center cohort study.

BACKGROUND: Ovarian cancer screening in BRCA1/2 mutation carriers utilizes assessment of carbohydrate antigen 125 (CA125) and transvaginal ultrasound (TVU), despite low sensitivity and specificity. We evaluated the association between CA125 levels, BRCA1/2 mutation status and menopausal status to provide more information on clinical conditions that may influence CA125 levels. METHODS: We retrospectively analyzed repeated measurements of CA125 levels and clinical data of 466 women at high risk for ovarian cancer. CA125 levels were compared between women with and without deleterious mutations in BRCA1/2. Pearson's correlation was used to determine the association between age and CA125 serum level. Differences in CA125 levels were assessed with the Mann-Whitney U test. The effect of BRCA1/2 mutation status and menopausal status on the change in CA125 levels was determined by Two-factor analysis of variance (ANOVA). RESULTS: The CA125 serum levels of premenopausal women (median, 13.8 kU/mL; range, 9.4 - 19.5 kU/mL) were significantly higher than in postmenopausal women (median, 10.4 kU/mL; range, 7.7 - 14.0 kU/mL; p < .001). There was no significant difference in the CA125 levels of BRCA mutation carriers and non-mutation carriers across all age groups (p = .612). When investigating the combined effect of BRCA1/2 mutation and menopausal status, variance analysis revealed a significant interaction between BRCA1/2 mutation status and menopausal status on CA125 levels (p < .001). There was a significant difference between the CA125 levels of premenopausal and postmenopausal women, with a large effect in BRCA mutation carriers (p < .001, d = 1.05), whereas in non-mutation carriers there was only a small effect (p < .001, d = 0.32). CONCLUSION: Our findings suggest that hereditary mutations in BRCA1/2 affect the decline of CA125 levels with increasing age. To prove a definite effect of this mutation on the CA125 level, prospective trials need to be conducted to define new cut-off levels of CA 125 in mutation carriers and optimize ovarian cancer screening.

Familial breast cancer, pregnancy and cardiotoxicity associated with the use of doxorubicin and reaction with trastuzumab.

INTRODUCTION: Breast Cancer (BC) is a neoplasm with the highest prevalence in women in Brazil and worldwide. Pregnancy-associated with BC is defined as that which occurs during pregnancy or within 1 to 2 years postpartum. The objective is to present a clinical case of a young patient with a history of familial BC who had cancer during pregnancy. The patient had cardiotoxicity after using doxorubicin and trastuzumab. CASE REPORT: She was a young patient within infiltrating ductal carcinoma in the right breast She was diagnosed within nine weeks of gestation and submitted to neoadjuvant chemotherapy with AC protocol (doxorubicina and cyclophosphamide) and mastectomy. Developed left atrial overload after treatment and still responding to hypersensitivity to trastuzumab. MANAGEMENT AND OUTCOME: The patient presented an alteration in the electrocardiogram (ECG) after the use of doxorubicin. The exam was repeated and the ECG was normal. Trastuzumab was started after delivery and the patient had a hypersensitivity reaction. Administration of trastuzumab was stopped and hydrocortisone was administered. The patient showed improvement in symptoms with cessation of trastuzumab. DISCUSSION: Although anthracycline-induced cardiotoxicity and hypersensitivity reactions to trastuzumab are common reactions, there are few studies on the effects of these drugs in patients with Gestational breast cancer (GBC). Monitoring cardiotoxicity in breast cancer treatment in pregnant patients is essential to avoid two complications: for the pregnant woman and the fetus.

Low BRCA1 and BRCA2 Germline Mutation Rates in a French-Canadian Population with a Diagnosis of Epithelial Tubo-Ovarian Carcinoma.

OBJECTIVE: Universal genetic testing has become increasingly important in the management of epithelial tubo-ovarian and peritoneal carcinoma. Worldwide, reported incidences of deleterious BRCA mutations vary between 12% and 15%. We sought to evaluate the incidence in our population, given its specific genetic background (French-Canadian ancestry). METHOD: Mainstream genetic testing was implemented in our service in May 2017 and offered to all patients with epithelial tubo-ovarian or peritoneal carcinomas, except mucinous and borderline tumours. Data were prospectively collected in a database and retrospectively analyzed. RESULTS: We tested 222 patients in our centre, of whom 183 (82.4%) had high-grade serous carcinoma (HGSC). Overall, 139 patients had no identified mutation (62.6%). Deleterious BRCA1 and BRCA2 mutations were found in 12 patients (5.4%): 6 had BRCA1, and 6 BRCA2 mutations; 11 of these patients had HGSC. Other non-BRCA mutations (ATM, RAD51C, RAD51D, BRIP1, CDH1, MRE11, MSH6, MUTYH, PALB2, and PMS2) were observed in an additional 20 patients (9.0%), of whom 18 had HGSC. A total of 63 different variants of unknown significance (VUS) were found, of which 4 were in the BRCA1 and BRCA2 genes. Deleterious mutations were not identified in clear cell carcinomas, and only 1 was found in low-grade serous carcinoma. CONCLUSION: In our French-Canadian population, the incidence of deleterious germline BRCA mutations was surprisingly low at 5.4%-less than half that reported in the literature. This may affect patient response to poly (ADP-ribose) polymerase (PARP) inhibitor (PARPi) therapy. Mainstream genetic testing was successfully implemented in our service and facilitated access to genetic testing in our patient population.

[Clinical-based study of ovarian cancer patients with and without BRCA1/2 genes mutation: clinical features and pedigree analysis].

Objective: To compare the clinical and histological features and prognosis of patients with ovarian cancer from different genetic background, and to make further understanding of the genetic model of BRCA genes used pedigree analysis. Methods: There were 71 patients from 67 independent families enrolled in our study from Apr. 2000 to Jun. 2009 in Peking Union Medical College Hospital. All exons of BRCA1/2 genes were analyzed using denaturing high-performance liquid chromatography(DHPLC) followed by direct sequencing, and clinical features of patients were compared by statistical analysis. Pedigree analysis of two families with BRCA genes mutation were performed. Results: The mutation rate of BRCA genes was 28% (20/71). The frequency of BRCA1 and BRCA2 gene mutation was 23% (16/71) and 6% (4/71), respectively (P=0.004). Histology types of patients with and without BRCA genes mutation were different. The onset age between patients with and without BRCA genes mutation was similar (52.6 versus 54.6 years old, P=0.393), and tend to be early-onset breast or ovarian cancer in high-risk group. There was no significant difference of platinum-resistant rate, disease free survival and overall survival rate between patients with and without BRCA genes mutation (all P>0.05). According to the pedigree analysis, up to 100% of female offspring inherited pathogenic mutations, and male offspring could be a mutation carrier. Conclusions: The genetic screening and clinical intervention should be performed as early as possible for the members from families at risk of hereditary ovarian cancer. Genetic consulting is important for patients with high-grade papillary serous adenocarcinoma of ovary. It is still unknown that whether the patients with BRCA gene mutations have better prognosis than sporadic ones, and further perspective, randomized controlled trial is still needed.

[Clinical significance and distribution of BRCA genes mutation in sporadic high grade serous ovarian cancer].

Objective: To investigate the mutations of BRCA genes in sporadic high grade serous ovarian cancer (HGSOC) and study its clinical significance. Methods: Sixty-eight patients between January 2015 and January 2016 from the Affiliated Cancer Hospital of Zhengzhou University were collected who were based on pathological diagnosis of ovarian cancer and had no reported family history, and all patients firstly hospitalized were untreated in other hospitals before. (1) The BRCA genes were detected by next-generation sequencing (NGS) method. (2) The serum tumor markers included carcinoembryonic antigen (CEA), CA(125), CA(199), and human epididymis protein 4 (HE4) were detected by the chemiluminescence methods, and their correlation was analyzed by Pearson linear correlation. Descriptive statistics and comparisons were performed using two-tailed t-tests, Pearson's chi square test, Fisher's exact tests or logistic regression analysis as appropriate to research the clinicopathologic features associated with BRCA mutations, including age, International Federation of Gynecology and Obstetrics (FIGO) stage, platinum-based chemotherapy sensitivity, distant metastases, serum tumor markers (STM) . Results: (1) Fifteen cases (22%, 15/68) BRCA mutations were identified (BRCA1: 11 cases; BRCA2: 4 cases), and four novel mutations were observed. (2) The levels of CEA, CA(199), and HE4 were lower in BRCA mutations compared to that in control group, while no significant differences were found (P>0.05), but the level of CA(125) was much higher in BRCA mutation group than that in controls (t=-3.536, P=0.003). Further linear regression analysis found that there was a significant linear correlation between CA(125) and HE4 group (r=0.494, P<0.01), and the same correlation as CEA and CA(199) group (r=0.897, P<0.01). (3) Single factor analysis showed that no significant differences were observed in onset age, FIGO stage, distant metastasis, and STM between BRCA(+) and BRCA(-) group (P>0.05), while significant differences were found in CA(125) and sensitivity to platinum-based chemotherapy between the patients with BRCA mutation and wild type (P<0.05). The multiple factors analysis showed that the high level of CA(125) was a independent risk factor of BRCA mutations in sporadic HGSOC (P=0.007). Conclusion: The combination of CA(125) with BRCA have great clinical significance, the mutation of BRCA gene could guild the clinical chemotherapy regiments.

Clinical Application of Poly(ADP-Ribose) Polymerase Inhibitors in High-Grade Serous Ovarian Cancer.

UNLABELLED: : High-grade serous ovarian cancer is characterized by genomic instability, with one half of all tumors displaying defects in the important DNA repair pathway of homologous recombination. Given the action of poly(ADP-ribose) polymerase (PARP) inhibitors in targeting tumors with deficiencies in this repair pathway by loss of BRCA1/2, ovarian tumors could be an attractive population for clinical application of this therapy. PARP inhibitors have moved into clinical practice in the past few years, with approval from the Food and Drug Administration (FDA) and European Medicines Agency (EMA) within the past 2 years. The U.S. FDA approval of olaparib applies to fourth line treatment in germline BRCA-mutant ovarian cancer, and European EMA approval to olaparib maintenance in both germline and somatic BRCA-mutant platinum-sensitive ovarian cancer. In order to widen the ovarian cancer patient population that would benefit from PARP inhibitors, predictive biomarkers based on a clear understanding of the mechanism of action are required. Additionally, a better understanding of the toxicity profile is needed if PARP inhibitors are to be used in the curative, rather than the palliative, setting. We reviewed the development of PARP inhibitors in phase I-III clinical trials, including combination trials of PARP inhibitors and chemotherapy/antiangiogenics, the approval for these agents, the mechanisms of resistance, and the outstanding issues, including the development of biomarkers and the rate of long-term hematologic toxicities with these agents. IMPLICATIONS FOR PRACTICE: The poly(ADP-ribose) polymerase (PARP) inhibitor olaparib has recently received approval from the Food and Drug Administration (FDA) and European Medicines Agency (EMA), with a second agent (rucaparib) likely to be approved in the near future. However, the patient population with potential benefit from PARP inhibitors is likely wider than that of germline BRCA mutation-associated disease, and biomarkers are in development to enable the selection of patients with the potential for clinical benefit from these agents. Questions remain regarding the toxicities of PARP inhibitors, limiting the use of these agents in the prophylactic or adjuvant setting until more information is available. The indications for olaparib as indicated by the FDA and EMA are reviewed.

Usefulness of Canadian Public Health Insurance Administrative Databases to Assess Breast and Ovarian Cancer Screening Imaging Technologies for BRCA1/2 Mutation Carriers.

PURPOSE: In Canada, recommendations for clinical management of hereditary breast and ovarian cancer among individuals carrying a deleterious BRCA1 or BRCA2 mutation have been available since 2007. Eight years later, very little is known about the uptake of screening and risk-reduction measures in this population. Because Canada's public health care system falls under provincial jurisdictions, using provincial health care administrative databases appears a valuable option to assess management of BRCA1/2 mutation carriers. The objective was to explore the usefulness of public health insurance administrative databases in British Columbia, Ontario, and Quebec to assess management after BRCA1/2 genetic testing. METHODS: Official public health insurance documents were considered potentially useful if they had specific procedure codes, and pertained to procedures performed in the public and private health care systems. RESULTS: All 3 administrative databases have specific procedures codes for mammography and breast ultrasounds. Only Quebec and Ontario have a specific procedure code for breast magnetic resonance imaging. It is impossible to assess, on an individual basis, the frequency of others screening exams, with the exception of CA-125 testing in British Columbia. Screenings done in private practice are excluded from the administrative databases unless covered by special agreements for reimbursement, such as all breast imaging exams in Ontario and mammograms in British Columbia and Quebec. There are no specific procedure codes for risk-reduction surgeries for breast and ovarian cancer. CONCLUSION: Population-based assessment of breast and ovarian cancer risk management strategies other than mammographic screening, using only administrative data, is currently challenging in the 3 Canadian provinces studied.

Male Breast Cancer With Dual BRCA2 and BRIP1 Deleterious Gene Mutations.

Background: Male breast cancer remains relatively underexplored in the medical literature. At present, male patients with breast cancer follow the same treatment guidelines as female patients with breast cancer, principally because of similar outcomes with treatment. However, this practice should not preclude generating evidence for male breast cancer surveillance, diagnosis, and management. BRCA2 gene mutations are associated with an increased risk of male breast cancer, along with lesser-known gene mutations that could also increase this risk, such as mutations of the BRIP1 gene. This case report presents a male patient with dual BRCA2 and BRIP1 deleterious gene mutations. To our knowledge, this combination has not been reported in the medical literature to date. Case Report: A 53-year-old male presented with a palpable symptomatic mass underneath the right nipple-areolar complex. Biopsies confirmed a poorly differentiated, infiltrating ductal carcinoma that was estrogen and progesterone receptor positive and human epidermal growth factor receptor-2 negative. The patient underwent a left modified radical mastectomy, with a right prophylactic simple mastectomy. Postoperatively, he underwent adjuvant chemotherapy and endocrine therapy. Conclusion: This novel case of genetically based male breast cancer with dual deleterious gene mutations provides insight into current treatment recommendations and the subtle differences between male breast cancer and female breast cancer. Engaging in discussions surrounding such rare cases not only raises awareness of male breast cancer but also indicates the need for further research aimed at establishing evidence-based management strategies for male patients with breast cancer.

A case of double-negative prostate cancer with BRCA2 mutation and high tumor mutation burden treated sequentially with olaparib and pembrolizumab.

Introduction: Double-negative prostate cancer, an androgen receptor-independent prostate cancer without features of neuroendocrine tumors, is refractory to treatment but could be an ideal candidate for individualized treatment. Case presentation: An 85-year-old patient with metastatic castration-resistant prostate cancer without prostate-specific antigen progression presented with local recurrence and liver and lung metastases 6 months after orchiectomy and apalutamide. A liver tumor biopsy led to a diagnosis of double-negative prostate cancer. FoundationOne® CDx showed BRCA2 mutation and high tumor mutation burden. Olaparib and pembrolizumab were administered sequentially, and the patient responded to each treatment for 5 months until radiographic progression. Conclusion: Sequential use of olaparib and pembrolizumab may be effective for double-negative prostate cancer with BRCA2 mutations and high tumor mutation burden.

BRCA-mutated gastric adenocarcinomas are associated with chromosomal instability and responsiveness to platinum-based chemotherapy.

BACKGROUND: Homologous recombination defect is an important biomarker of chemotherapy in certain tumor types, and the presence of pathogenic or likely pathogenic mutations involving BRCA1 or BRCA2 (p-BRCA) mutations is the most well-established marker for the homologous recombination defect. Gastric cancer, one of the most prevalent tumor types in Asia, also harbors p-BRCA mutations. METHODS: To investigate the clinical significance of p-BRCA mutations, we analyzed 366 gastric cancer cases through next-generation sequencing. We determined the zygosity of p-BRCA mutations based on the calculated tumor purity through variant allelic fraction patterns and investigated whether the presence of p-BRCA mutations is associated with platinum-based chemotherapy and a certain molecular subtype. RESULTS: Biallelic p-BRCA mutation was associated with better response to platinum-based chemotherapy than heterozygous p-BRCA mutation or wild type BRCA genes. The biallelic p-BRCA mutations was observed only in the chromosomal instability subtype, while all p-BRCA mutations were heterozygous in microsatellite instability subtype. CONCLUSIONS: In conclusion, patients with gastric cancer harboring biallelic p-BRCA mutations were associated with a good initial response to platinum-based chemotherapy and those tumors were exclusively chromosomal instability subtype. Further investigation for potential association with homologous recombination defect is warranted.

Sex Differences in Attitudes Toward Marriage and Childbearing Based on the Assumption of Being BRCA1/2 Mutation Carriers Among Young People.

PURPOSE: This study investigated changes in attitudes toward marriage and childbearing assuming a BRCA1/2 mutation carrier status among healthy, unmarried individuals in Korea. METHODS: A nationally representative sample of healthy, unmarried individuals aged 20-39 years was surveyed. A questionnaire on marriage and childbearing intentions was administered to the participants before and after providing them with information on BRCA1/2 mutation carriers' breast and ovarian cancer risks and their autosomal dominant inheritance pattern. The participants were asked about their attitudes toward childbearing through preimplantation genetic diagnosis (PGD). RESULTS: Of the participants who initially wanted to marry, the assumption that they or their partners had BRCA1/2 mutation caused 25.3% to no longer want to get married and 36.2% to change their attitude from wanting to bear children to no longer wanting them. Females were more likely than males to change their attitudes toward marriage and childbearing. The participants who had negative attitudes toward genetic testing were more likely to change their attitudes regarding marriage and childbearing than those who were favorable toward both disclosure and testing. More than 50% of the participants who did not want children were willing to bear children through PGD when it was assumed that they were BRCA mutation carriers. CONCLUSION: On the assumption of being carriers, general, young, and healthy females were more likely than males to negatively change their attitudes toward marriage and childbearing. Public education on the implications of living with mutation carriers and reproductive options may be required.

Clinical characteristics of patients with Breast and / or Ovarian Cancer with mutations in the BRCA1 and BRCA2 genes in Córdoba, Argentina / [Características clínicas de pacientes con Cáncer de Mama y / o Cáncer de Ovario con mutaciones en los genes BRCA1 y BRCA2 en Córdoba, Argentina.]

Introduction: Hereditary predisposition syndromes to cancer represent 5-10% of cancer cases, the most studied being HBOC produced by mutations in the BRCA1/2 genes. Objectives: To describe clinical, histopathological and PV characteristics in patients with HBOC in Córdoba, Argentina and compare it with those without BRCA1/2 mutations. Methods: Cross-sectional, correlational and observational analysis of patients from Córdoba. The ANOVA, Student's t test contingency tables and Fisher exact test were used the significance level was α = 0.05. Results: 155 women with BC, OC and BC/OC were studied. 40 BRCA1 / 2 mutations were identified. No differences were found in the age of diagnosis between patients with and without BRCA1/2 mutations. A significant association was found between VP in BRCA1/2 and the type of cancer (p = 0.003); all cases with BC/OC presented mutations in BRCA1/2. No significant association was found between mutated/non-mutated and personal history, family background, and ER-PR-HER2. 23.1% and 38.1% of BC cases were TN in individuals with VP in BRCA 1 and 2, respectively. The prevalence of mutations was 25.8% and the prevalence of novel PV was 10.0%. Conclusions: Patients with BC-VP BRCA1/2 are associated with ductal histology, and younger age of presentation with VP BRCA1. We did not find significant differences in the age at diagnosis of BC between patients with BRCA1 and BRCA2 mutations, a higher proportion of BC TN is observed than in the general population. In our sample, the prevalence of BRCA1/2 mutations among patients who meet criteria for HBOC is 25.8%, with 10% new pathogenic variant.

Introducción: Los síndromes de predisposición hereditaria al cáncer representan un 5-10% de los casos de cáncer, el más estudiado es HBOC producido por mutaciones en los genes BRCA1/2. Objetivos: Describir características clínicas, histopatológicas y VP en pacientes con HBOC en Córdoba, Argentina y compararla con aquellas sin mutaciones en BRCA1/2. Métodos: Análisis transversal, correlacional y observacional de pacientes de Córdoba. Se utilizó la prueba ANOVA, t de Student, tablas de contingencia y prueba exacta de Fisher, el nivel de significancia fue α=0,05. Resultados: Se estudiaron 155 mujeres con CM, CO y CM/CO. Se identificaron 40 mutaciones en BRCA1/2. No se encontraron diferencias en edad de diagnóstico entre pacientes con y sin mutaciones en BRCA1/2. Se encontró asociación significativa entre VP en BRCA1/2 y el tipo de cáncer (p=0,003); todos los casos con CM/CO presentaron mutaciones en BRCA1/2. No se encontró asociación significativa entre mutados/no mutados y AP, AF, RE-RP-HER2. El 23.1% y 38.1% de los casos de CM fueron TN en individuos con VP en BRCA 1 y 2 respectivamente. La prevalencia de mutaciones fue 25,8% y la prevalencia de VP noveles del 10,0%. Conclusiones: Las pacientes con CM-VP BRCA1/2 están asociadas con histología ductal, y menor edad de presentación con VP BRCA1. No encontramos diferencias significativas en edad de diagnóstico del CM entre pacientes con mutaciones BRCA1 y BRCA2, se observa una mayor proporción CM TN que en la población en general. En nuestra muestra, la prevalencia de mutaciones en BRCA1/2 entre los pacientes que reúnen criterios para HBOC es del 25,8%, con 10% de VP noveles.

[PARP Inhibitors: From the Mechanism of Action to Clinical Practice]. / Inibidores da PARP: do mecanismo de ação à prática clínica.

Repairing damage and errors that occur in the DNA molecule is essential to maintain the integrity of the genome and cell viability. Deficits in DNA repair mechanisms lead to an increased risk of genetic instability and contribute to neoplastic transformation. Poly (ADP-ribose) polymerases (PARP) are a group of enzymes that play a key role in signalling and repairing DNA errors. The inhibition of its activity is a therapeutic strategy that takes advantage of the mechanism of synthetic lethality and that can be used in the treatment of tumours with specific defects in DNA repair pathways, namely in tumours with mutations in the tumour suppressor genes BRCA1 and BRCA2. There are several PARP inhibitors (iPARP), already approved by the USA Food and Drug Administration and the European Medicines Agency used in the treatment of breast, ovarian, pancreatic and prostate cancer. However, as with other target therapies, despite being well tolerated and widely used in the clinical practice, iPARP resistance is common and can be developed through various molecular mechanisms. In this article, we intend to make an updated review on iPARP and its main role in tumour cells, highlighting the several resistance mechanisms that have been recently revealed, as well as the current clinical applications and toxicity associated with this target therapy.

A reparação dos danos que ocorrem na molécula de ADN é fundamental para manter a integridade do genoma e a viabilidade celular. Défices nos mecanismos de reparação desta molécula cursam com um aumento do risco para instabilidade genética e contribuem para a transformação neoplásica. As poly (ADP-ribose) polymerases (PARP) são um grupo de enzimas que apresentam um papel chave na sinalização e reparação dos erros no ADN. A inibição da sua atividade é uma estratégia terapêutica que tira partido do mecanismo de letalidade sintética e que pode ser usada no tratamento de tumores com defeitos específicos nas vias de reparação de ADN, nomeadamente em tumores com mutações nos genes supressores tumorais BRCA1 e BRCA2. Existem vários inibidores das PARP (iPARP) já aprovados pela Food and Drug Administration dos Estados Unidos da América e pela Agência Europeia do Medicamento e utilizados no tratamento do cancro da mama, ovário, pâncreas e próstata. No entanto, tal como acontece com outras terapias alvo, a resistência aos iPARP é comum apesar de bem tolerados e amplamente utilizados na prática clínica, e pode desenvolver-se através de vários mecanismos moleculares. Neste artigo, pretendemos realizar uma revisão atualizada sobre os iPARP e o seu principal modo de ação em células tumorais, dando a conhecer os vários mecanismos de resistência que têm sido recentemente revelados, assim como as atuais aplicações clínicas e a toxicidade associada a esta terapia alvo.

Comparing breast cancer imaging characteristics of CHEK2 with BRCA1 and BRCA2 gene mutation carriers.

PURPOSE: Breast cancer gene (BRCA) 1 and 2 mutations are frequently studied gene mutations (GM); the incidence of checkpoint kinase 2 (CHEK2) is increasing. We describe the imaging features of breast cancer (BC) in CHEK2 mutations, compared to BRCA 1 and 2 using mammography, ultrasound (US) and magnetic resonance imaging (MRI). METHOD: Inclusion criteria were primary BC in GM carriers, treated in the same hospital. Age at diagnosis, histology, hormone receptor and human epidermal growth factor receptor 2 (HER2) status were retrieved. Mammography descriptors were mass, asymmetry and suspicious microcalcifications. The enhancement pattern (MRI), shape and border, architectural distortion, the presence of a hyperechoic rim and cystic complex structure (US) were documented. Analyses were performed using SAS software (version 9.4). Fishers' exact test was used to test associations between two categorical variables. RESULTS: In 191 women, 233 malignant lesions were diagnosed (78 in BRCA1, 109 in BRCA2, 46 in CHEK2). In CHEK2 carriers, mammographically, suspicious microcalcifications (54%) were more prevalent (BRCA2 (48%) and BRCA1 carriers (33%)) (p-value = 0.057) compared to mass lesions (35%). On US, lesions were most frequently ill-defined (86%) (p = 0.579) and irregular (94.5%) (p = 0.098) compared to BRCA2 (77% and 80% resp.) and BRCA1 carriers (71% and 72% resp.). On MRI, mass lesions showed a type 3 curve in CHEK2 (67%) compared to BRCA1 (36%) and BRCA2 (50%) (p = 0.056). CONCLUSIONS: Malignant radiological characteristics of breast cancer, more specifically suspicious microcalcifications, were more frequently seen in CHEK2 and BRCA2 compared to BRCA1 mutation carriers (without a significant difference) indicating the importance of mammography in follow-up of CHEK2 carriers.

TP53 variants in p53 signatures and the clonality of STICs in RRSO samples.

OBJECTIVE: Precursor lesions may be identified in fallopian tube tissue after risk-reducing salpingo-oophorectomy (RRSO) in patients with pathogenic variants of BRCA1/2. Serous tubal intraepithelial carcinoma (STIC) is considered a precursor of high-grade serous carcinoma, whereas the significance of the p53 signature remains unclear. In this study, we investigated the relationship between the p53 signature and the risk of ovarian cancer. METHODS: We analyzed the clinicopathological findings and conducted DNA sequencing for TP53 variants of p53 signatures and STIC lesions isolated using laser capture microdissection in 13 patients with pathogenic variants of BRCA1/2 who underwent RRSO and 17 control patients with the benign gynecologic disease. RESULTS: TP53 pathogenic variants were detected significantly higher in RRSO group than control (p<0.001). No difference in the frequency of p53 signatures were observed between groups (53.8% vs 29.4%; p=0.17). TP53 sequencing and next-generation sequencing analysis in a patient with STIC and occult cancer revealed 2 TP53 mutations causing different p53 staining for STICs and another TP53 mutation shared between STIC and occult cancer. CONCLUSION: The sequence analysis for TP53 revealed 2 types of p53 signatures, one with a risk of progression to STIC and ovarian cancer with pathological variants in TP53 and the other with a low risk of progression without pathological variants in TP53 as seen in control.

Comparisons of survival outcomes between bevacizumab and olaparib in BRCA-mutated, platinum-sensitive relapsed ovarian cancer: a Korean Gynecologic Oncology Group study (KGOG 3052).

OBJECTIVE: To compare survival outcomes between bevacizumab (BEV) and olaparib (OLA) maintenance therapy in BRCA-mutated, platinum-sensitive relapsed (PSR) high-grade serous ovarian carcinoma (HGSOC). METHODS: From 10 institutions, we identified HGSOC patients with germline and/or somatic BRCA1/2 mutations, who experienced platinum-sensitive recurrence between 2013 and 2019, and received second-line platinum-based chemotherapy. Patients were divided into BEV (n=29), OLA (n=83), and non-BEV/non-OLA users (n=36). The OLA and non-BEV/non-OLA users were grouped as the OLA intent group. We conducted 1:2 nearest neighbor-matching between the BEV and OLA intent groups, setting the proportion of OLA users in the OLA intent group from 65% to 100% at 5% intervals, and compared survival outcomes among the matched groups. RESULTS: Overall, OLA users showed significantly better progression-free survival (PFS) than BEV users (median, 23.8 vs. 17.4 months; p=0.004). Before matching, PFS improved in the OLA intent group but marginal statistical significance (p=0.057). After matching, multivariate analyses adjusting confounders identified intention-to-treat OLA as an independent favorable prognostic factor for PFS in the OLA 65P (adjusted hazard ratio [aHR]=0.505; 95% confidence interval [CI]=0.280-0.911; p=0.023) to OLA 100P (aHR=0.348; 95% CI=0.184-0.658; p=0.001) datasets. The aHR of intention-to-treat OLA for recurrence decreased with increasing proportions of OLA users. No differences in overall survival were observed between the BEV and OLA intent groups, and between the BEV and OLA users. CONCLUSION: Compared to BEV, intention-to-treat OLA and actual use of OLA maintenance therapy were significantly associated with decreased disease recurrence risk in patients with BRCA-mutated, PSR HGSOC.

Peripheral blood BRCA1 methylation profiling to predict familial ovarian cancer.

OBJECTIVE: Familial cancer appears at a young age and its incidence is increasing. About 12% of familial ovarian cancer cases are associated with BRCA1/2 mutations (BRCAm). In this study, we investigated BRCA1 methylation may predict ovarian cancer in those with a family history of cancer (FHC) but without BRCA1/2 mutations (BRCAwt). METHODS: Using peripheral blood DNA from 55 subjects without a history of cancer [cancer(-)] and 52 ovarian cancer patients, we examined BRCA1 promoter methylation through bisulfite sequencing of the promoter and expressed the results as the cumulative methylation index. Then, we evaluated the BRCA1 promoter methylation according to BRCA1/2 germline mutations. RESULTS: BRCA1 methylation was more prevalent in the BRCAm cancer(-) group than in the BRCAwt cancer(-) group and ovarian cancer patients (p=0.031 and p=0.019, respectively). In the BRCAwt cancer(-) group, BRCA1 methylation was more prevalent in those with an FHC than in those without one and in the BRCAm cancer(-) group with an FHC (p=0.001 and p<0.001, respectively). CONCLUSION: Our data suggest a predictive role of BRCA1 methylation profile for ovarian cancer in those without a history of cancer but with an FHC. BRCA1 methylation has important implications for diagnostic and predictive testing of those with BRCAwt cancer(-) status with FHC.

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.

BRCA1/2 mutation status in patients with metachronous breast and ovarian malignancies: clues towards the implementation of genetic counseling.

OBJECTIVE: The characteristics of patients with metachronous breast and ovarian malignancies and the pathogenic role of BRCA1/2 mutations remain poorly understood. We investigated these issues through a review of hospital records and nationwide Taiwanese registry data, followed by BRCA1/2 mutation analysis in hospital-based cases. METHODS: We retrospectively retrieved consecutive clinical records of Taiwanese patients who presented with these malignancies to our hospital between 2001 and 2017. We also collected information from the Data Science Center of the Taiwan Cancer Registry (TCR) between 2007 and 2015. Next-generation sequencing and multiplex ligation-dependent probe amplification were used to identify BRCA1/2 mutations and large genomic rearrangements, respectively. When BRCA1/2 mutations were identified in index cases, pedigrees were reconstructed and genetic testing was offered to family members. RESULTS: A total of 12,769 patients with breast cancer and 1,537 with ovarian cancer were retrieved from our hospital records. Of them, 28 had metachronous breast and ovarian malignancies. We also identified 113 cases from the TCR dataset. Eighteen hospital-based cases underwent BRCA1/2 sequencing and germline pathogenic mutations were detected in 7 patients (38.9%, 5 in BRCA1 and 2 in BRCA2). All BRCA1/2 mutation carriers had ovarian high-grade serous carcinomas. Of the 12 patients who were alive at the time of analysis, 5 were BRCA1/2 mutation carriers. All of them had family members with BRCA1/2-associated malignancies. CONCLUSIONS: Our results provide pilot evidence that BRCA1/2 mutations are common in Taiwanese patients with metachronous breast and ovarian malignancies, supporting the clinical utility of genetic counseling.