Germline Mutations In BRCA1 Research Articles

A novel cancer risk prediction score for the natural course of FA patients with biallelic BRCA2/FANCD1 mutations.

Biallelic germline mutations in BRCA2 occur in the Fanconi anemia (FA)-D1 subtype of the rare pediatric disorder, FA, characterized clinically by severe congenital abnormalities and a very high propensity to develop malignancies early in life. Clinical and genetic data from 96 FA-D1 patients with biallelic BRCA2 mutations were collected and used to develop a new cancer risk prediction score system based on the specific mutations in BRCA2. This score takes into account the location of frameshift/stop and missense mutations relative to exon 11 of BRCA2, which encodes the major sites for interaction with the RAD51 recombinase, and uses the MaxEnt and HBond splicing scores to analyze potential splice site perturbations. Among 75 FA-D1 patients with ascertained BRCA2 mutations, 66 patients developed 102 malignancies, ranging from one to three independent tumors per individual. The median age at the clinical presentation of peripheral embryonal tumors was 1.0, at the onset of hematologic malignancies 1.8 and at the manifestation of CNS tumors 2.7years, respectively. Patients who received treatment lived longer than those without. Using our novel scoring system, we could distinguish three distinct cancer risk groups among FA-D1 patients: in the first, patients developed their initial malignancy at a median age of 1.3years (n = 36, 95% CI = 0.9-1.8), in the second group at 2.3years (n = 17, 95% CI = 1.4-4.4) and in the third group at 23.0years (n = 22, 95% CI = 4.3-n/a). Therefore, this scoring system allows, for the first time, to predict the cancer manifestation of FA-D1 patients simply based on the type and position of the mutations in BRCA2.

Phase II Trials of Iniparib (BSI-201) in Combination with Gemcitabine and Carboplatin in Patients with Recurrent Ovarian Cancer.

Iniparib (BSI-201), a novel anticancer agent thought to have poly(ADP-ribose) polymerase (PARP) inhibitory activity and synergy with both gemcitabine and carboplatin (GC) was evaluated in 2 cohorts with GC. Parallel multicenter, single-arm, phase II studies using a Simon two-stage design. Eligible patients had a histological diagnosis of epithelial ovarian carcinoma, fallopian tube cancer, or primary peritoneal carcinoma and demonstration of platinum-sensitive (≥6 months [mo]) or -resistant disease (relapse 2-6 mo post-platinum). Carboplatin (AUC 4 IV day 1), gemcitabine (1000 mg/m2 IV days 1 and 8), and iniparib (5.6 mg/kg IV days 1, 4, 8, and 11) were given on a 21-day cycle. The overall response rate (ORR RECIST 1.0) in platinum sensitive disease was 66% (95% CI, 49-80) with a higher response rate in the 15 pts with germline BRCA mutations (gBRCAmut) (73%). Median PFS was 9.9 (95% CI, 8.2-11.3) months. In the platinum resistant population the ORR was 26% (95% CI, 14-42), however in the 11 pts for whom BRCA mutation was present, the best overall response was PR in 5 (46%). Median PFS was 6.8 months (range, 5.7-7.7 months). Notably, among the 17 CA-125-response-evaluable patients who did not achieve tumor response, 7 (41.2%) patients had a CA125 response, and 93% has clinical benefit (CR + PR + SD). The GCI combination was generally well tolerated despite a high incidence of thrombocytopenia and neutropenia, with no new toxicities. Given the subsequent lack of efficacy demonstrated for iniparib in breast cancer, these are studies of GC and demonstrate a higher than traditionally appreciated activity in patients with platinum-sensitive and -resistant recurrent ovarian cancer, especially in patients that harbor a BRCA mutation, resetting the benchmark for efficacy in phase II trials. (ClinicalTrials.gov Identifiers: NCT01033292 & NCT01033123).

Abstract PR006: Integrating noise into a signal: Luminal epithelial cells integrate variable responses to aging into stereotypical changes that underlie breast cancer susceptibility

Abstract Effects from aging in any single cell are unpredictable, whereas aging phenotypes at the organ and tissue levels tend to appear as stereotypical changes. The mammary epithelium, the origin of breast carcinomas, is a bilayer of two major phenotypically and functionally distinct cell lineages, the luminal epithelial and myoepithelial cells. We have shown that luminal epithelia exhibit substantial stereotypical changes with age, which merits attention as they are putative breast cancer cells of origin. Hallmark aging changes in mammary gland are loss of lineage specificity in luminal epithelia exemplified by acquiring expression of proteins normally reserved for myoepithelial cells, and progenitor cells that accumulate and attain a basal differentiation bias. We hypothesize that effects from aging that impinge upon maintenance of lineage specificity increases susceptibility to cancer initiation. Indeed, histologically normal breast tissue from young women, who were known to be highly susceptible to breast cancer because they harbor a germline mutation in BRCA1, BRCA2, or PALB2 genes, exhibited hallmarks of accelerated aging. These included increased proportions of luminal epithelial cells with acquired myoepithelial proteins, acceleration of a breast specific biological clock by 10 to 40 years compared to chronological age, and a basal differentiation bias or failure of differentiation of cKit+ progenitors. To gain insight into the underlying molecular changes we interrogated transcriptomes, proteomes, and methylomes of mammary epithelia at lineage resolution. Strikingly, age-dependent differential gene expression and DNA methylation occurred almost exclusively in luminal epithelia, whereas changes due to increased variance of gene and protein expression occurs in both luminal and myoepithelial lineages. Most gene changes that were previously associated with early breast cancer are detectable as age-driven changes in normal luminal epithelia. The genes with age-dependent differential and variant changes in expression distinguish normal tissue from breast cancers and are predictive of PAM50 breast cancer subtypes. Heterochronus, multilineage, co-cultures demonstrated that the age-dependent phenotype of luminal cells is at least partly dependent on the microenvironment created on the apical surfaces of neighboring myoepithelial cells. We show that increased variance is a substantial outcome of aging and is likely central to understanding increased susceptibility to breast cancer with age. We speculate that the luminal epithelium is a site of integration of the variant responses to aging in their surrounding tissue, and that their emergent phenotype of aging both endows cells with the ability to become a cancer cell of origin and embodies a biosensor that presages one’s cancer susceptibility. Citation Format: Masaru Miyano, Rosalyn W. Sayaman, Parijat Senapati, Stefan Hinz, Victoria E. Seewaldt, Dustin Schones, Mark A. LaBarge. Integrating noise into a signal: Luminal epithelial cells integrate variable responses to aging into stereotypical changes that underlie breast cancer susceptibility [abstract]. In: Proceedings of the AACR Special Conference: Aging and Cancer; 2022 Nov 17-20; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_1):Abstract nr PR006.

Profiling of the genetic features of Chinese patients with gastric cancer with HRD germline mutations in a large-scale retrospective study

BackgroundApproximately 10% of gastric cancers (GCs) are associated with strong familial clustering and can be attributed to genetic predisposition. Homologous recombination deficiency (HRD) leads to genomic instability and accumulation of...

Validation of multi-gene panel next-generation sequencing for the detection of BRCA mutation in formalin-fixed, paraffin-embedded epithelial ovarian cancer tissues

ObjectiveThe therapeutic effect of poly (ADP-ribose) polymerase (PARP) inhibitors in patients with epithelial ovarian cancer (EOC) with somatic BRCA mutations is consistent with that observed in patients with germline BRCA mutations, indicating the importance of detecting both germline and somatic BRCA mutations concurrently. We compared the efficacy of multi-gene panel next generation sequencing (NGS) in EOC patients’ formalin-fixed, paraffin-embedded (FFPE) tissue to that of conventional Sanger sequencing in blood samples. Materials and methodsThis study included 48 patients with EOC, and both blood Sanger sequencing and FFPE tissue NGS were conducted in all of them. Clinical and pathological data were reviewed, including age at diagnosis, histology, and stage. Blood Sanger sequencing was performed using peripheral blood leukocytes. The target regions of 90 cancer-related genes were identified using FFPE tissue. ResultsThe median age of patients was 56.1 years, with serous carcinoma (n = 40, 83.3%) and stage III (n = 37, 77.1%) being the most common histology and International Federation of Gynecology and Obstetrics (FIGO) stage, respectively. FFPE tissue NGS identified ten pathogenic variants, including all eight pathogenic variants identified by blood Sanger sequencing and two additional pathogenic variants. Furthermore, FFPE tissue NGS identified 19 variants of uncertain significance (VUS), including all ten VUS identified by blood Sanger sequencing and nine additional VUS. ConclusionThe FFPE tissue multi-gene panel NGS had 100% sensitivity for detecting BRCA germline mutations and could detect additional somatic mutations. Furthermore, performing FFPE tissue multi-gene panel NGS followed by blood Sanger sequencing sequentially may help differentiate germline from somatic BRCA mutations for genetic counseling.

Pancreatic ductal adenocarcinoma complete regression after preoperative chemotherapy: Surgical results in a small series

BackgroundPancreatic ductal adenocarcinoma (PDAC) becomes a systemic disease from an early stage. Complete surgical resection remains the only validated and potentially curative treatment; disappointingly only 20% of patients present with a resectable tumour. Although a complete pathological regression (pCR) after the preoperative chemotherapy could intuitively lead to better outcomes and prolonged survival some reports highlighted significant rates of recurrence. Cases PresentationWe describe three cases of pCR following preoperative chemotherapy for PDAC. The first two cases received neoadjuvant mFOLFIRINOX and PAX-G scheme for borderline resectable PDAC. Recurrence appeared 9 and 12 months after surgery. Although both patients started adjuvant therapy straight after the diagnosis of recurrence, the disease rapidly progressed and led them to death 12 and 15 months after surgery. The third case was characterized by germline BRCA2 mutation. The patient presented with PDAC of the body, intrapancreatic biliary stenosis and suspected peritoneal metastasis. One year later, after first and second-line chemotherapy, she underwent explorative laparoscopy and total spleno-pancreatectomy without evidence of viable tumour cells in the surgical specimen. At six months she is recurrence-free. ConclusionsVery few reports describe a complete pathological response following preoperative chemotherapy in pancreatic cancer. We observed three cases in the last three years with disappointing oncological results. Further investigations are needed to predict PDAC prognosis in pCR after chemotherapy.

Clinical Use of PARP Inhibitors in BRCA Mutant and Non-BRCA Mutant Breast Cancer.

The use of poly(ADP-ribose) polymerase (PARP) inhibitors for the treatment of patients with germline BRCA mutations (gBRCAm) and breast cancer, both in the early and advanced settings, is a success of genomically-directed treatment. These agents have been shown to be associated with longer progression-free survival when compared to standard chemotherapy, with an acceptable toxicity profile. A recent randomized trial demonstrated improved survival with the use of olaparib for 2years compared to placebo in patients with early-stage high risk gBRCAm associated breast cancer. Ongoing research efforts are focused on identifying patients beyond those with BRCA1/2 or PALB2 mutations who may benefit from PARP inhibitors, exploring the overlapping mechanisms of resistance between platinum and PARP inhibitors and developing agents with less toxicity that will allow combinational strategies.

Oxaliplatin prior to PARP inhibitor in BRCA-mutated ovarian cancer.

The use of PARP inhibitor (PARPi) has shown a considerable benefit in progression-free survival (PFS) in relapsed, platinum-sensitive epithelial ovarian cancer (OC). Our study aimed to investigate the impact of the last platinum-based chemotherapy treatment in response to PARPi. Retrospective cohort study. The study involved 96 consecutive, pretreated, platinum-sensitive advanced OC patients. Demographics and clinical data were retrieved from clinical records. PFS and overall survival (OS) were calculated from the start of PARPi. Germline BRCA mutation was investigated in all cases. Platinum-based chemotherapy before PARPi maintenance therapy included pegylated liposomal doxorubicin-oxaliplatin (PLD-Ox) in 46 patients (48%) and other platinum-based chemotherapy in 50 patients (52%). During a median follow-up of 22 months from the beginning of PARPi therapy, 57 patients relapsed (median PFS: 12 months) and 64 patients died (median OS: 23 months). During multivariable analysis, receiving PLD-Ox before PARPi was associated with improved PFS [hazard ratio (HR): 0.46, 95% CI: 0.26-0.82] and OS (HR: 0.48, 95% CI: 0.27-0.83). In 36 BRCA-mutated patients, PLD-Ox was associated with improved PFS (2-year PFS: 70.0% versus 25.0%, p = 0.02). Receiving PLD-Ox before PARPi may improve prognosis in platinum-sensitive advanced OC patients and may provide advantages in the BRCA-mutated subgroup.

Germline BRCA testing in pancreatic cancer: improving awareness, timing, turnaround, and uptake.

Prognosis is generally poor for patients with pancreatic ductal adenocarcinoma. However, patients with germline BRCA1 or BRCA2 mutations (gBRCAm) may benefit from first-line platinum-based chemotherapy and maintenance therapy with the poly(adenosine diphosphate-ribose) polymerase inhibitor olaparib following at least 16 weeks of first-line platinum-based chemotherapy without disease progression. Germline breast cancer gene (BRCA) testing is therefore important to ensure that patients receive the most effective treatment. In addition, testing for other DNA damage response gene mutations beyond gBRCAm may also guide treatment decisions. However, clinical pathways for genetic testing are often suboptimal, leading to delays in treatment initiation or missed opportunities for personalized therapy. Barriers to testing include low rates of referral and uptake, delays to referral and slow result turnaround times, cost, and biopsy and assay limitations if somatic testing is performed, leading to the requirement for subsequent dedicated germline testing. Low rates of referral may result from lack of awareness among physicians of the clinical value of testing, coupled with low confidence in interpreting test results and poor availability of genetic counseling services. Among patients, barriers to uptake may include similar lack of awareness of the clinical value of testing, anxiety regarding the implications of test results, lack of insurance coverage, fear of negative insurance implications, and socioeconomic factors. Potential solutions include innovative approaches to testing pathways, including 'mainstreaming' of testing in which BRCA tests are routinely arranged by the treating oncologist, with the involvement of genetic counselors if a patient is found to have a gBRCAm. More recently, the utility of multigene panel analyses has also been explored. Access to genetic counseling may also be improved through initiatives such as having a genetic counseling appointment for all new patient visits and telemedicine approaches, including the use of telephone consultations or DVD-assisted counseling. Educational programs will also be beneficial, and cost effectiveness is likely to improve as the number of targeted treatments increases and when the earlier detection of tumors in family members following cascade testing is considered.

PARP Inhibitors in the Treatment of Prostate Cancer: From Scientific Rationale to Clinical Development.

Prostate cancer (PC) treatment has reached a milestone with the introduction of poly(ADP-ribose) polymerase (PARP) inhibitors. PARP inhibitors (PARPi) induce breaks in single-stranded and/or double-stranded DNA, resulting in synthetic lethality in cancer cells lacking functional homologous recombination genes. Around 20% to 25% of patients with metastatic castration-resistant prostate cancer harbor mutations in DNA damage repair genes, either somatic or germline. The success of PARPi in these patients has prompted studies exploring its potential in tumors classified as "BRCAness," which refers to tumors without germline BRCA1 or BRCA2 mutations. Additionally, there is a proposed connection between androgen receptor signaling and synthetic lethality of PARPi. The inclusion of genetic mutation tests in the treatment algorithm for PC is a significant step towards precision and personalized medicine, marking a first in the field. The objectives of this review encompass understanding the mechanism of action of PARPi in both monotherapy and combination therapy, exploring patient selection criteria, discussing pivotal studies that led to its approval, and offering future prospects. However, numerous unanswered questions remain, including the identification of the patient population that could benefit most from PARPi, determining whether to use PARPi as monotherapy or in combination, and finding the optimal timing of PARPi administration in advanced or localized disease. To address these questions, several ongoing clinical trials are being conducted.

High grade acinic cell carcinoma of the breast with clear cytoplasm mimics clear cell carcinoma in a BRCA1 mutation carrier: a case report and review of the literature on the molecular analysis.

Acinic cell carcinoma of the breast is an extremely rare tumor. To the best of our knowledge, only one case is reported to have bilateral tumors and had both BRCA1 and TP53 mutation. Herein, we report another case of acinic cell carcinoma of the breast in a 29-years-old female carrying germline BRCA1 and TP53 mutation, and the tumor showed a complex combination of histological features which had not only the reported common features such as diffuse infiltrative small acinar or glandular structures mixed with solid nests, but also the uncommon widespread clear cells, high grade tumor cells. The immunohistochemical profile of the tumor cells was strongly positive for lysozyme and triple negative for ER, PR, HER2. Although she had bilateral high grade breast cancers, this patient refused postoperative adjuvant therapy this time and has been doing well in the past 12 months. As a rare form of triple-negative breast cancer with a relatively not so bad prognosis, more reports are needed to understand its biological characteristics.

Genetic Counseling, Screening and Risk-Reducing Surgery in Patients with Primary Breast Cancer and Germline BRCA Mutations: Unmet Needs in Low- and Middle-Income Countries.

Worldwide genetic counseling practices are variable and often not reported in low- and middle-income countries (LMICs). We present the follow-up genetic counseling, breast screening, risk-reducing salpingo-oophorectomy (RRSO) and contralateral prophylactic mastectomy (CPM) in a cohort of study patients with either BRCA pathogenic mutations or BRCA variant of unknown significance (VUS). Chart review and phone calls for the collection of information. Out of a cohort of 250 patients, 14 had deleterious mutations and 31 had a VUS, of whom 19 had primary early breast cancer. We collected information about genetic counseling, screening, CPM and RRSO. Fourteen patients with deleterious mutations (7 BRCA1 and 7 BRCA2) and 19 patients with VUS mutations (20 VUS, 4 BRCA1, 16 BRCA2; 1 patient had both) were surveyed. Of 14 patients with deleterious BRCA mutations, 57.14% (8/14 patients) received genetic counseling from their oncologist. Subsequently 85.71% (12/14) are undergoing mammography screening and 35.71% (5/14) breast screening magnetic resonance imaging (MRI). Furthermore, 50% of them underwent CPM and 57.14% underwent RRSO. Of 19 patients with VUS mutations, 10.5% received genetic counseling from their oncologist; 78.9% were undergoing regular screening mammogram and 31.5% were undergoing breast MRI; one patient underwent CPM and two patients RRSO. Within three years from knowing they have a mutation, 50% of patients with germline BRCA mutations had undergone CPM and 60% RRSO, the majority of them had screening mammography surveillance but only 50% had screening MRI. Follow-up of patients with VUS with mammography was 78% but MRI was only 31%. Lack of MRI surveillance reflects both limited resources and insufficient counseling. Genetic counseling was done by medical oncologists, which reflects a trend in LMIC. Our Data shows the importance of the need for professional genetic counselors and optimal surveillance in Lebanon and other LMICs.

Ovarian cancer onset across different BRCA mutation types: a view to a more tailored approach for BRCA mutated patients

ObjectiveTo evaluate the role of different specific types of germline breast cancer susceptibility BRCA mutations on the age of onset of high grade serous ovarian cancer.MethodsThis was a multicenter, international,...

Pathologic complete response following FOLFIRINOX and olaparib treatment for hepatic metastasized pancreatic ductal adenocarcinoma with a germline BRCA mutation.

A 47-year-old female who was previously treated for BRCA1 germline mutant breast cancer presented with increasing back pain. Radiological and pathological investigations led to the diagnosis of pancreatic ductal adenocarcinoma with multiple hepatic metastases. Serum carbohydrate antigen 19-9 levels were highly elevated at 14,784 U/mL (normal, < 37 U/mL). After nine cycles of FOLFIRINOX treatment, radiological findings revealed remarkable shrinkage of the primary pancreatic tumor, disappearance of hepatic metastases, and normalized levels of carbohydrate antigen 19-9 levels. Because of increased neuropathy following FOLFIRINOX treatment, the patient was switched to maintenance olaparib treatment. Ten months later, her radiological response and normalized carbohydrate antigen 19-9 levels were stable. After staging laparoscopy, the patient underwent laparoscopic distal pancreatectomy as a conversion surgery. Histopathological examination revealed no signs of residual adenocarcinoma in the resected pancreatic specimens, which was diagnosed as a pathological complete response. The patient recovered without complications. Adjuvant olaparib treatment was administered with no signs of recurrence at 7 months after surgery. In conclusion, a pathologic complete response after FOLFIRINOX and olaparib maintenance treatment in hepatic metastasized pancreatic ductal adenocarcinoma is extremely rare. These bridging treatments may contribute to increased surgical resection rates and improved survival rates.

All HER2-negative breast cancer patients need gBRCA testing: cost-effectiveness and clinical benefits

BackgroundThe OlympiA trial demonstrated the benefits of adjuvant usage of olaparib for high-risk patients with human epidermal growth factor receptor 2 (HER2)-negative breast cancer (BC) and germline BRCA (gBRCA) mutation. This provoked thoughts on the clinical criteria of gBRCA testing. This study aims to estimate the costs and benefits of gBRCA testing and adjuvant olaparib therapy for patients with triple-negative breast cancer (TNBC) and hormone-receptor (HR)-positive and HER2-negative BC in China and the United States of America (USA).MethodsWe used a Markov chain decision tree analytic model to compare three gBRCA screening policies in China and the USA: (1) no gBRCA testing; (2) selected gBRCA testing and (3) universal gBRCA testing for nonmetastatic TNBC and HR-positive HER2-negative BC patients. We modelled the benefit of systemic therapy and risk-reducing surgeries among patients identified with pathogenic or likely pathogenic variants (PVs) in BRCA1 and BRCA2.ResultsChanging from the selected gBRCA testing to the universal gBRCA testing in TNBC patients is cost-effective, with the incremental cost-effectiveness ratios (ICERs) being 10991.1 and 56518.2 USD/QALY in China and the USA, respectively. Expanding universal gBRCA testing to HR-positive HER2-negative BC and TNBC patients has ICERs of 2023.3 and 16611.1 USD/QALY in China and the USA, respectively.DiscussionBy performing gBRCA testing on all HER2-negative BC patients, adjuvant olaparib can be offered to high-risk patients with a PV in BRCA1 or BRCA2. These patients are also candidates for risk-reducing surgeries, an important aspect of their survivorship care, and these interventions can improve survival outcomes. With the willingness-to-pay thresholds being 31,500.0 and 100,000.0 USD per QALY gained in China and the USA, respectively, universal gBRCA testing is likely cost-effective for all HER2-negative BC patients. This simplified criterion of gBRCA testing for BC is recommended for adoption by current guidelines in China and the USA.

Metastatic colorectal cancer as the primary phenotype in a hereditary breast and ovarian cancer patient with Germline BRCA1 mutation: a case report

Hereditary breast and ovarian cancer (HBOC) syndrome has increased predisposition to breast and/or ovarian cancer, and 24% of families with HBOC were associated with the germline pathogenic variants in BRCA1/2. Timely diagnosis and identification of mutation carriers is of utmost importance to improve survival benefit and quality of life. Cancers that have been included into screening of BRCA1/2 associated HBOC included prostate and pancreatic cancers etc. In this case, we reported a patient who firstly presented symptoms of CRC and was finally diagnosed as BRCA1 associated HBOC with advanced peritoneal carcinoma. With strategies of cetuximab based treatment and olaparib, and debulking surgeries, she has achieved an overall survival (OS) > 35 months. The aim was to indicate that HBOC might also first present as CRC, and comprehensive next-generation sequencing analysis might be a key complement for screening and diagnose of HBOC.

NGS-based targeted gene mutational profiles in Korean patients with pancreatic cancer

According to molecular profiling studies, a considerable number of patients with pancreatic cancer harbor potentially actionable mutations. However, there are limited relevant data from the Korean population. We assessed the molecular profiles of patients with pancreatic cancer in Korea. This study collected molecular profiling data from patients with pancreatic cancer who visited Seoul National University Bundang Hospital between March 2018 and August 2020. Formalin-fixed, paraffin-embedded tumor specimens were sequenced using a targeted next-generation sequencing (NGS) platform. Cancer-associated mutations were analyzed, and potentially actionable mutations were identified. Potentially actionable mutations were classified into “highly actionable” and “modifies options” based on the Know Your Tumor registry study. In total, 87 patients with NGS tumor panel data were identified. Sixty-one patients (70.1%) had metastatic disease at the time of tissue acquisition. Tissues were obtained from the primary tumors and metastatic sites in 41 (47.1%) and 46 (52.9%) patients, respectively. At least one pathogenic mutation was reported in 86 patients (98.9%). The frequencies of four common mutations in our cohort were similar to those in The Cancer Genome Atlas data. Potentially actionable mutations were identified in 27 patients (31.0%). Of these, mutations categorized as highly actionable and modifies options were identified in 12 (13.8%) and 18 patients (20.7%), respectively. The most frequent highly actionable mutations were located in DNA damage response genes, such as BRCA1, BRCA2, or ATM (n = 6, 6.9%). Two patients with germline BRCA1 mutations received maintenance poly(adenosine diphosphate-ribose) polymerase inhibitor therapy. One patient has been receiving maintenance treatment for 18 months while remaining in radiologically complete remission. Mutational profiles using targeted NGS in Korean patients with pancreatic cancer were similar to those in Western patients. The present study supports the clinical potential and possible expanded clinical use of genetic profiling.

Pamiparib in patients with locally advanced or metastatic HER2-negative breast cancer with germline BRCA mutations: a phase II study

PurposeTo evaluate the efficacy and safety of pamiparib in patients with locally advanced or metastatic human epidermal growth factor receptor 2-negative (HER2−) breast cancer, with deleterious or suspected deleterious germline BRCA1/2 mutations (gBRCA1/2 m).MethodsIn this open-label, phase II, multicenter study in China (NCT03575065), patients with triple-negative breast cancer (TNBC cohort) or hormone receptor-positive (HR+)/HER2− breast cancer (HR+/HER2− cohort) and ≤ 2 prior lines of chemotherapy received pamiparib 60 mg orally twice daily in 28-day, continuous cycles. The primary endpoint was objective response rate (ORR; RECIST v1.1) by independent review committee.ResultsIn total, 88 patients were enrolled (TNBC cohort: 62; HR+/HER2− cohort: 26). Median age was 45.5 (range: 27–67) years, and 60 patients (68.2%) had received 1 or 2 prior lines of chemotherapy; 42 patients (47.7%) had previously received platinum chemotherapy. In the TNBC cohort, ORR was 38.2% (95% confidence interval [CI] 25.4–52.3) and median duration of response (DoR) was 7.0 months (95% CI 3.9–not estimable). In the HR+/HER2− cohort, ORR was 61.9% (95% CI 38.4–81.9) and median DoR was 7.5 months (95% CI 5.6–14.8). The most common treatment-emergent adverse events (TEAEs), treatment-related TEAEs, and ≥ Grade 3 TEAEs were hematologic (including anemia, decreased neutrophil count, and decreased white blood cell count). Overall, 64.8% of patients had TEAEs leading to dose reduction and 2.3% had TEAEs leading to treatment discontinuation.ConclusionPamiparib showed encouraging efficacy and an acceptable safety profile in patients with locally advanced and metastatic HER2− breast cancer with gBRCA1/2 m.Trial registrationClinicalTrials.gov, NCT03575065; July 2, 2018.

PP121 Comparison of genomic and transcriptional homologous recombination deficiency assays in breast cancer patients with germline BRCA mutations

PP121 Comparison of genomic and transcriptional homologous recombination deficiency assays in breast cancer patients with germline BRCA mutations

CTIM-02. TIP: PHASE I/II STUDY OF STEREOTACTIC RADIOSURGERY WITH CONCURRENT OLAPARIB FOLLOWED BY ADJUVANT DURVALUMAB AND PHYSICIAN’S CHOICE SYSTEMIC THERAPY IN SUBJECTS WITH BREAST CANCER BRAIN METASTASES

Abstract BACKGROUND Despite progress in the treatment of brain metastasis (BrM) for HER2+ breast cancer (BC), outcomes for patients with HER2-negative BC BrM remain poor. Current standard of care consists of local therapies, including surgery and radiotherapy, followed by systemic therapy. Preclinical studies show inhibitors of poly(ADP-ribose) polymerase (PARP) are effective with radiation therapy as a DNA damage response inhibitor. Triple negative BC (TNBC) has higher rates of homologous recombination deficiency compared to other BC subtypes, and together with HER2-negative, BRCA-mutated BC would be particularly sensitive to PARP inhibition. PARP inhibition also shows promising efficacy combined with immunotherapy in patients with germline BRCA-mutant and metastatic TNBC in clinical trials (MEDIOLA, TOPACIO). In addition, immunotherapy with stereotactic radiosurgery (SRS) is associated with favorable intracranial control and survival in patients with BrM. We hypothesize that this biologically-rational combination will enhance local control of SRS-treated BrM through synergy with PARP inhibition, while controlling micrometastatic disease in the brain and extracranial sites via potentiation of the immune response. METHOD We are conducting a multi-institution, Phase I/II trial of SRS plus olaparib, followed by durvalumab (with physician’s choice systemic therapy), for patients with TNBC (any BRCA status) or HER2-negative with BRCA-mutated (germline or somatic) BC BrM [NCT04711824]. The primary objectives are to evaluate safety and tolerability (Phase I) and determine intracranial disease control at 6 months (Phase II) of this treatment combination. Secondary objectives include determining clinical activity via intracranial and global progression-free survival, overall survival, and intracranial and extracranial response rate. Exploratory objectives will assess potential biomarkers of treatment response, including changes in circulating tumor cells and DNA in blood and cerebrospinal fluid, germline and tumor mutations in DNA repair pathway genes, and PD-L1 expression, as well as quality of life and patient-reported outcomes. A surgical sub-study will evaluate olaparib concentration/distribution in resected BrM.