Banu Arun

Oral poly(ADP-ribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and advanced breast cancer: a proof-of-concept trial

BACKGROUND Olaparib, a novel, orally active poly(ADP-ribose) polymerase (PARP) inhibitor, induced synthetic lethality in BRCA-deficient cells. A maximum tolerated dose and initial signal of efficacy in BRCA-deficient ovarian cancers have been reported. We therefore assessed the efficacy, safety, and tolerability of olaparib alone in women with BRCA1 or BRCA2 mutations and advanced breast cancer. METHODS Women (aged >or=18 years) with confirmed BRCA1 or BRCA2 mutations and recurrent, advanced breast cancer were assigned to two sequential cohorts in a phase 2 study undertaken in 16 centres in Australia, Germany, Spain, Sweden, the UK, and the USA. The first cohort (n=27) was given continuous oral olaparib at the maximum tolerated dose (400 mg twice daily), and the second (n=27) was given a lower dose (100 mg twice daily). The primary efficacy endpoint was objective response rate (ORR). This study is registered with ClinicalTrials.gov, number NCT00494234. FINDINGS Patients had been given a median of three previous chemotherapy regimens (range 1-5 in cohort 1, and 2-4 in cohort 2). ORR was 11 (41%) of 27 patients (95% CI 25-59) in the cohort assigned to 400 mg twice daily, and six (22%) of 27 (11-41) in the cohort assigned to 100 mg twice daily. Toxicities were mainly at low grades. The most frequent causally related adverse events in the cohort given 400 mg twice daily were fatigue (grade 1 or 2, 11 [41%]; grade 3 or 4, four [15%]), nausea (grade 1 or 2, 11 [41%]; grade 3 or 4, four [15%]), vomiting (grade 1 or 2, three [11%]; grade 3 or 4, three [11%]), and anaemia (grade 1 or 2, one [4%]; grade 3 or 4, three [11%]). The most frequent causally related adverse events in the cohort given 100 mg twice daily were nausea (grade 1 or 2, 11 [41%]; none grade 3 or 4) and fatigue (grade 1 or 2, seven [26%]; grade 3 or 4, one [4%]). INTERPRETATION The results of this study provide positive proof of concept for PARP inhibition in BRCA-deficient breast cancers and shows a favourable therapeutic index for a novel targeted treatment strategy in patients with tumours that have genetic loss of function of BRCA1-associated or BRCA2-associated DNA repair. Toxicity in women with BRCA1 and BRCA2 mutations was similar to that reported previously in those without such mutations. FUNDING AstraZeneca.

Significantly Higher Pathologic Complete Remission Rate After Neoadjuvant Therapy With Trastuzumab, Paclitaxel, and Epirubicin Chemotherapy: Results of a Randomized Trial in Human Epidermal Growth Factor Receptor 2–Positive Operable Breast Cancer

PURPOSE The objective of this study was to determine whether the addition of trastuzumab to chemotherapy in the neoadjuvant setting could increase pathologic complete response (pCR) rate in patients with human epidermal growth factor receptor 2 (HER2) -positive disease. PATIENTS AND METHODS Forty-two patients with HER2-positive disease with operable breast cancer were randomly assigned to either four cycles of paclitaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide or to the same chemotherapy with simultaneous weekly trastuzumab for 24 weeks. The primary objective was to demonstrate a 20% improvement in pCR (assumed 21% to 41%) with the addition of trastuzumab to chemotherapy. The planned sample size was 164 patients. RESULTS Prognostic factors were similar in the two groups. After 34 patients had completed therapy, the trials Data Monitoring Committee stopped the trial because of superiority of trastuzumab plus chemotherapy. pCR rates were 25% and 66.7% for chemotherapy (n = 16) and trastuzumab plus chemotherapy (n = 18), respectively (P = .02). The decision was based on the calculation that, if study continued to 164 patients, there was a 95% probability that trastuzumab plus chemotherapy would be superior. Of the 42 randomized patients, 26% in the chemotherapy arm achieved pCR compared with 65.2% in the trastuzumab plus chemotherapy arm (P = .016). The safety of this approach is not established, although no clinical congestive heart failure was observed. A more than 10% decrease in the cardiac ejection fraction was observed in five and seven patients in the chemotherapy and trastuzumab plus chemotherapy arms, respectively. CONCLUSION Despite the small sample size, these data indicate that adding trastuzumab to chemotherapy, as used in this trial, significantly increased pCR without clinical congestive heart failure.

Phase II Study of Weekly Docetaxel and Trastuzumab for Patients With HER-2–Overexpressing Metastatic Breast Cancer

PURPOSE To evaluate the safety and efficacy of weekly docetaxel plus trastuzumab in women with HER-2-overexpressing metastatic breast cancer. Efficacy was correlated with serum HER-2 extracellular domain (ECD) levels. PATIENTS AND METHODS Thirty women with metastatic breast cancer were treated with weekly docetaxel and trastuzumab as first- or second-line therapy. Both docetaxel 35 mg/m(2)/wk and trastuzumab 2 mg/kg/wk were delivered in 4-week cycles consisting of three weekly treatments followed by 1 week of rest. A loading dose of trastuzumab 4 mg/kg was administered 1 day before the start of the first cycle. RESULTS The median delivered dose-intensity of docetaxel was 24 mg/m(2)/wk (range, 18 to 27 mg/m(2)/wk). The intent-to-treat overall response rate (ORR) was 63% (95% confidence interval [CI], 44% to 80%). The ORR in patients whose tumors were HER-2-positive by fluorescence in situ hybridization was 67% (16 of 24 patients; 95% CI, 45% to 84%). In patients with elevated serum HER-2 ECD at baseline, the ORR was 76% (95% CI, 53% to 92%), compared with 33% (95% CI, 7% to 70%) in patients with low HER-2 ECD levels (P =.04). Variations in HER-2 ECD concentrations during treatment correlated with response to treatment. Median time to progression was 9 months. Acute toxicity, including myelosuppression, was mild. Fatigue, fluid retention, and excessive tearing became more common with repetitive dosing. CONCLUSION Weekly docetaxel and trastuzumab is an active combination for treating patients with HER-2-overexpressing metastatic breast cancer. Serum HER-2 ECD testing may be a promising method for monitoring patients on trastuzumab-based therapy.

American Society of Clinical Oncology Policy Statement Update: Genetic and Genomic Testing for Cancer Susceptibility

The American Society of Clinical Oncology (ASCO) has long affirmed that the recognition and management of individuals with an inherited susceptibility to cancer are core elements of oncology care. ASCO released its first statement on genetic testing in 1996 and updated that statement in 2003 and 2010 in response to developments in the field. In 2014, the Cancer Prevention and Ethics Committees of ASCO commissioned another update to reflect the impact of advances in this area on oncology practice. In particular, there was an interest in addressing the opportunities and challenges arising from the application of massively parallel sequencing-also known as next-generation sequencing-to cancer susceptibility testing. This technology introduces a new level of complexity into the practice of cancer risk assessment and management, requiring renewed effort on the part of ASCO to ensure that those providing care to patients with cancer receive the necessary education to use this new technology in the most effective, beneficial manner. The purpose of this statement is to explore the challenges of new and emerging technologies in cancer genetics and provide recommendations to ensure their optimal deployment in oncology practice. Specifically, the statement makes recommendations in the following areas: germline implications of somatic mutation profiling, multigene panel testing for cancer susceptibility, quality assurance in genetic testing, education of oncology professionals, and access to cancer genetic services.

Clinical and Pathologic Characteristics of Patients With BRCA-Positive and BRCA-Negative Breast Cancer

PURPOSE Mutations in the BRCA1 and BRCA2 genes confer greater risk of developing breast cancer. We determined whether tumor pathologic features and clinical features differ in patients with and without BRCA mutations. PATIENTS AND METHODS Tumor pathologic features and clinical characteristics were examined in 491 women with breast cancer who underwent genetic testing for BRCA mutations between 1997 and 2006. A retrospective review of medical records was conducted to determine clinical characteristics including ethnicity, age and clinical stage at diagnosis, age at parity, number of full-term pregnancies, use of oral contraceptives and hormone replacement therapy, and BRCA mutation status. Tumor pathology was reviewed to determine histologic type, tumor grade, and estrogen receptor, progesterone receptor, and HER-2/neu status. RESULTS Of the 491 patients with identified breast cancers, 391 patients were BRCA negative, and 86 patients were BRCA positive. Triple-negative breast cancer (ie, those with negative estrogen receptor, progesterone receptor, and HER-2/neu status) was diagnosed in 57.1% of the BRCA1-positive patients, 23.3% of the BRCA2-positive patients, and 13.8% of the BRCA-negative patients. BRCA1 mutation carriers had higher nuclear grade tumors than the other two groups (P < .001). Of the triple-negative cancer patients, BRCA2 mutation carriers were older when diagnosed than BRCA1 mutation carriers and noncarriers (P < .01). CONCLUSION These results suggest that tumors associated with BRCA1 mutations may be divided into two distinct groups, triple-negative and non-triple-negative groups. Future studies should seek to determine whether patients with BRCA1 mutations and triple-negative breast cancer respond to treatment better than BRCA-negative patients with similar tumor pathology.

Incidence and Outcome of BRCA Mutations in Unselected Patients with Triple Receptor-Negative Breast Cancer

Purpose: To investigate the incidence of germline and somatic BRCA1/2 mutations in unselected patients with triple-negative breast cancer (TNBC) and determine the prognostic significance of carrying a mutation. Methods: DNA was obtained from 77 TNBC and normal tissues. BRCA1/2 exons/flanking regions were sequenced from tumor and patients classified as mutant or wild type (WT). Sequencing was repeated from normal tissue to identify germline and somatic mutations. Patient characteristics were compared with chi-square. Survival was estimated by Kaplan–Meier method and compared with log-rank. Cox proportional hazards models were fit to determine the independent association of mutation status with outcome. Results: Median age was 51 years (27–83 years). Fifteen patients (19.5%) had BRCA mutations: 12 (15.6%) in BRCA1 (one somatic), and 3 (3.9%) in BRCA2. Patients with BRCA mutations tended to be younger than WT, (P = 0.005). Grade, histology, and stage were not associated with mutation status. At a median follow-up of 43 months (7–214 months), there were 33 (42.9%) recurrences and 35 (45.5%) deaths. Five-year recurrence-free survival estimates were 51.7% for WT versus 86.2% for patients with mutations, (P = 0.031); and 5-year overall survival estimates were 52.8% for WT versus 73.3% for patients with mutations (P = 0.225). After adjustment, patients with BRCA mutations had a significantly better RFS (HR: 0.19, 95% CI: 0.045–0.79, P = 0.016) compared with WT. Conclusions: In this unselected cohort of TNBC, we found a 19.5% incidence of BRCA mutations. Genetic testing should be discussed with patients with TNBC. Patients with TNBC with BRCA mutations had a significantly lower risk of relapse. Clin Cancer Res; 17(5); 1082–9. ©2011 AACR.

Progress in Chemoprevention Drug Development: The Promise of Molecular Biomarkers for Prevention of Intraepithelial Neoplasia and Cancer—A Plan to Move Forward

This article reviews progress in chemopreventive drug development, especially data and concepts that are new since the 2002 AACR report on treatment and prevention of intraepithelial neoplasia. Molecular biomarker expressions involved in mechanisms of carcinogenesis and genetic progression models of intraepithelial neoplasia are discussed and analyzed for how they can inform mechanism-based, molecularly targeted drug development as well as risk stratification, cohort selection, and end-point selection for clinical trials. We outline the concept of augmenting the risk, mechanistic, and disease data from histopathologic intraepithelial neoplasia assessments with molecular biomarker data. Updates of work in 10 clinical target organ sites include new data on molecular progression, significant completed trials, new agents of interest, and promising directions for future clinical studies. This overview concludes with strategies for accelerating chemopreventive drug development, such as integrating the best science into chemopreventive strategies and regulatory policy, providing incentives for industry to accelerate preventive drugs, fostering multisector cooperation in sharing clinical samples and data, and creating public-private partnerships to foster new regulatory policies and public education.

Residual Risk of Breast Cancer Recurrence 5 Years After Adjuvant Therapy

There is limited prognostic information to identify breast cancer patients who are at risk for late recurrences after adjuvant or neoadjuvant systemic therapy (AST). We evaluated the residual risk of recurrence and prognostic factors of 2838 patients with stage I-III breast cancer who were treated with AST between January 1, 1985, and November 1, 2001, and remained disease free for 5 years. Residual recurrence-free survival was estimated from the landmark of 5 years after AST to date of first recurrence or last follow-up using the Kaplan-Meier method. The log-rank test (two-sided) was used to compare groups. Residual recurrence-free survival rates at 5 and 10 years were 89% and 80%, respectively, and 216 patients developed a recurrence event. The 5-year residual risks of recurrence for patients with stage I, II, and III cancers were 7% (95% confidence interval [CI] = 3% to 15%), 11% (95% CI = 9% to 13%), and 13% (95% CI = 10% to 17%), respectively (P = .02). In multivariable analysis, stage, grade, hormone receptor status, and endocrine therapy were associated with late recurrences. Breast cancer patients have a substantial residual risk of recurrence, and selected tumor characteristics are associated with late recurrences.

American society of clinical oncology clinical practice guideline update on the use of pharmacologic interventions including tamoxifen, raloxifene, and aromatase inhibition for breast cancer risk reduction.

PURPOSE To update the 2002 American Society of Clinical Oncology guideline on pharmacologic interventions for breast cancer (BC) risk reduction. METHODS A literature search identified relevant randomized trials published since 2002. Primary outcome of interest was BC incidence (invasive and noninvasive). Secondary outcomes included BC mortality, adverse events, and net health benefits. An expert panel reviewed the literature and developed updated consensus guidelines. Results Seventeen articles met inclusion criteria. In premenopausal women, tamoxifen for 5 years reduces the risk of BC for at least 10 years, particularly estrogen receptor (ER) -positive invasive tumors. Women < or = 50 years of age experience fewer serious side effects. Vascular and vasomotor events do not persist post-treatment across all ages. In postmenopausal women, raloxifene and tamoxifen reduce the risk of ER-positive invasive BC with equal efficacy. Raloxifene is associated with a lower risk of thromboembolic disease, benign uterine conditions, and cataracts than tamoxifen in postmenopausal women. No evidence exists establishing whether a reduction in BC risk from either agent translates into reduced BC mortality. Recommendations In women at increased risk for BC, tamoxifen (20 mg/d for 5 years) may be offered to reduce the risk of invasive ER-positive BC, with benefits for at least 10 years. In postmenopausal women, raloxifene (60 mg/d for 5 years) may also be considered. Use of aromatase inhibitors, fenretinide, or other selective estrogen receptor modulators to lower BC risk is not recommended outside of a clinical trial. Discussion of risks and benefits of preventive agents by health providers is critical to patient decision making.

Ductal Carcinoma in Situ: State of the Science and Roadmap to Advance the Field

PURPOSE Ductal carcinoma in situ (DCIS) is the fourth leading cancer for women in the United States. Understanding of the biology and clinical behavior of DCIS is imperfect. This article highlights the current knowledge base and the scientific roadmap needed to advance the field. METHODS This article is based on work done by and consultations obtained from leading experts in the field over a 6-month period that culminated in a full-day symposium designed to systematically review the most pertinent MEDLINE published reports and develop a roadmap to elucidate the molecular steps of carcinogenesis, reduce the extent or prevent the need for therapies, eliminate recurrences, and reduce morbidity. RESULTS Expression profiling of pure DCIS will help elucidate the molecular characteristics that distinguish high-risk lesions from clinically irrelevant lesions. The development of new methods of extracting RNA from processed tissues may provide opportunities for research. Mammography often underestimates the pathologic extent of DCIS; other imaging methods need to be investigated for detection and monitoring of disease stability or progression. Novel biologic agents are being delivered in neoadjuvant clinical trials, and alternative methods for breast irradiation are being studied. Future trials of treatment versus no treatment for biologically selected cases of DCIS should be developed. CONCLUSION There is a critical need for a concerted international effort among patients with DCIS, clinicians, and basic scientists to conduct the research necessary to improve fundamental understanding of the biology and clinical behavior of DCIS and prevent development of invasive breast cancer.