Publications by authors named "Aman U Buzdar"

Purpose: Metaplastic breast cancer (MpBC) is a rare subtype of breast cancer that is commonly triple-negative and poorly responsive to neoadjuvant therapy in retrospective studies.

Experimental Design: To better define clinical outcomes and correlates of response, we analyzed the rate of pathologic complete response (pCR) to neoadjuvant therapy, survival outcomes, and genomic and transcriptomic profiles of the pretreatment tumors in a prospective clinical trial (NCT02276443). A total of 211 patients with triple-negative breast cancer (TNBC), including 39 with MpBC, received doxorubicin-cyclophosphamide-based neoadjuvant therapy.

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Aromatase inhibitors (AIs) reduce breast cancer recurrence and prolong survival, but up to 30% of patients exhibit recurrence. Using a genome-wide association study of patients entered on MA.27, a phase III randomized trial of anastrozole versus exemestane, we identified a single nucleotide polymorphism (SNP) in CUB And Sushi multiple domains 1 (CSMD1) associated with breast cancer-free interval, with the variant allele associated with fewer distant recurrences.

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Objectives: Based on our previous findings that postmenopausal women with estrone (E1) and estradiol (E2) concentrations at or above 1.3 pg/ml and 0.5 pg/ml, respectively, after 6 months of adjuvant anastrozole therapy had a three-fold risk of recurrence, we aimed to identify a single-nucleotide polymorphism (SNP)-based model that would predict elevated E1 and E2 and then validate it in an independent dataset.

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Anastrozole is a widely prescribed aromatase inhibitor for the therapy of estrogen receptor positive (ER+) breast cancer. We performed a genome-wide association study (GWAS) for plasma anastrozole concentrations in 687 postmenopausal women with ER+ breast cancer. The top single-nucleotide polymorphism (SNP) signal mapped across SLC38A7 (rs11648166, P = 2.

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Importance: Pathologic complete response rate (pCR), the primary end point of the ACOSOG (American College of Surgeons Oncology Group) Z1041 (Alliance) trial, and disease-free survival (DFS) and overall survival (OS) in women with operable HER2-positive breast cancer are similar between treatment regimens.

Objective: To assess DFS and OS for patients treated with sequential vs concurrent anthracycline plus trastuzumab.

Design, Setting, And Participants: Phase 3 randomized clinical trial conducted at 36 centers in the continental United States and Puerto Rico.

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Background Tipifarnib is an orally active, competitive inhibitor of farnesyltransferase which has shown encouraging signs of activity either alone or when combined with other agents. Clinical studies of tipifarnib in combination with anti-estrogen therapy have yielded disappointing results. In contrast, tipifarnib appears to be synergistic in combination with anthracycline based chemotherapy.

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Background: Estrone (E1), the major circulating estrogen in postmenopausal women, promotes estrogen-receptor positive (ER+) breast tumor growth and proliferation. Two major reactions contribute to E1 plasma concentrations, aromatase (CYP19A1) catalyzed E1 synthesis from androstenedione and steroid sulfatase (STS) catalyzed hydrolysis of estrone conjugates (E1Cs). E1Cs have been associated with breast cancer risk and may contribute to tumor progression since STS is expressed in breast cancer where its activity exceeds that of aromatase.

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Purpose To determine the long-term prognosis in each phenotypic subset of breast cancer related to residual cancer burden (RCB) after neoadjuvant chemotherapy alone, or with concurrent human epidermal growth factor receptor 2 (HER2)-targeted treatment. Methods We conducted a pathologic review to measure the continuous RCB index (wherein pathologic complete response has RCB = 0; residual disease is categorized into three predefined classes of RCB index [RCB-I, RCB-II, and RCB-III]), and yp-stage of residual disease. Patients were prospectively observed for survival.

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Information on processes for trials assessing investigational therapeutics is sparse. We assessed the trial development processes within the Department of Investigational Cancer Therapeutics (ICT) at MD Anderson Cancer Center (Houston, TX) and analyzed their effects on the trial activation timeline and enrolment. Data were from a prospectively maintained registry that tracks all clinical studies at MD Anderson.

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Previous studies demonstrated poor response to neoadjuvant systemic therapy (NST) for breast cancer among black women and women who are overweight or obese, but this may be due to chemotherapy underdosing. We assessed associations of race, ethnicity, and body mass index (BMI) with pathologic complete response (pCR) in clinical trial populations. 1797 women enrolled in four NST trials (CALGB 40601, 40603; ACOSOG Z1041, Z1071) were included.

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In resource-constrained environments many patients with human epidermal growth factor receptor 2 (HER2)+ early breast cancer are currently not offered adjuvant anti-HER2 therapy. For patients who might be able to receive the tyrosine kinase inhibitor (TKI) lapatinib (e.g.

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Introduction: Worldwide, many patients with HER2+ (human epidermal growth factor receptor 2-positive) early breast cancer (BC) do not receive adjuvant trastuzumab. Hazards of recurrence of these patients with respect to hormone receptor status of the primary tumor have not been described.

Methods: Using data from 1,260 patients randomized to placebo in the adjuvant TEACH trial, we report 10-year annual hazards of recurrence in HER2+ patients not treated with anti-HER2 therapy.

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Background: To evaluate health related quality of life (HRQOL) in TEACH, a phase III randomized placebo controlled trial of 12 months of adjuvant lapatinib in HER2 positive (HER2+) early breast cancer which demonstrated marginal benefit in disease-free survival.

Methods: Women on TEACH completed the Short Form 36-item health survey (version2; SF-36v2) at the baseline, six and 12 months after therapy initiation and six monthly thereafter. Mean changes were compared between treatment groups for two summary measures (Physical and Mental Component Summary scores; PCS and MCS) and eight domain measures (physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional and mental health), and in patients discontinuing therapy.

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Purpose: We determined hormone concentrations (estradiol [E2], estrone [E1], estrone conjugates [E1-C], androstenedione [A], testosterone [T]) before and on anastrozole therapy where we also determined plasma concentrations of anastrozole and its metabolites.

Experimental: Postmenopausal women who were to receive adjuvant anastrozole for resected early breast cancer were studied. Pretreatment, blood samples were obtained for the acquisition of DNA and for plasma hormone measurements (E2, E1, E1-C, A, and T).

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Background: Neoadjuvant chemotherapy with trastuzumab for patients with HER2-positive breast cancer can produce a pathological complete response in the breast in 30-65% of patients. We investigated the effect of the timing of trastuzumab administration with anthracycline and taxane neoadjuvant chemotherapy.

Methods: This randomised trial was done at 36 centres in the USA and Puerto Rico.

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There has been significant progress in our basic understanding of drugs and targets in the management of breast cancer. Recent breast cancer clinical trials have examined whether combinations of drugs targeting transmembrane receptors or their downstream effectors involved in cell signal transduction can increase response rates and overcome acquired and/or de novo drug resistance compared to a single targeted agent with or without systemic chemotherapy. We reviewed published clinical trials and conference proceedings examining combinations of targeted therapies across different breast cancer subtypes.

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We performed a discovery genome-wide association study to identify genetic factors associated with variation in plasma estradiol (E2) concentrations using DNA from 772 postmenopausal women with estrogen receptor (ER)-positive breast cancer prior to the initiation of aromatase inhibitor therapy. Association analyses showed that the single nucleotide polymorphisms (SNP) (rs1864729) with the lowest P value (P = 3.49E-08), mapped to chromosome 8 near TSPYL5.

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Purpose: Mammographic breast density (MBD) is decreased by tamoxifen, but the effect of aromatase inhibitors is less clear.

Experimental Design: We enrolled early-stage postmenopausal patients with breast cancer initiating adjuvant aromatase inhibitor therapy and ascertained mammograms before and at an average 10 months of aromatase inhibitor therapy. We matched cases to healthy postmenopausal women (controls) from a large mammography screening cohort on age, baseline body mass index, baseline MBD, and interval between mammograms.

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Background: Worldwide, many patients with HER2-positive early stage breast cancer do not receive trastuzumab-the standard adjuvant treatment. We investigated the efficacy and safety of adjuvant lapatinib for patients with trastuzumab-naive HER2-positive early-stage breast cancer, started at any time after diagnosis.

Methods: This study was a placebo-controlled, multicentre, randomised phase 3 trial.

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Background: Trastuzumab is part of the standard treatment for patients with human epidermal growth factor receptor 2 (HER-2)-positive breast cancer, but not all patients respond to trastuzumab. Altered microRNA (miR) expression levels in cancer cells have been correlated with prognosis and response to chemotherapy. The authors of this report hypothesized that altered miR expression levels in plasma are associated with sensitivity to trastuzumab in patients with HER-2 positive breast cancer.

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Purpose: We investigated whether capecitabine and docetaxel followed by fluorouracil, epirubicin, and cyclophosphamide (FEC) or weekly paclitaxel (WP) followed by FEC would improve relapse-free survival (RFS) in operable breast cancer.

Patients And Methods: In this single-institution study, patients with clinical stages I to IIIC breast cancer were randomly assigned on a 1:1 basis to WP 80 mg/m(2) for 12 weeks followed by fluorouracil 500 mg/m(2), epirubicin 100 mg/m(2), and cyclophosphamide 500 mg/m(2) (FEC-100) every 3 weeks for four cycles or docetaxel 75 mg/m(2) on day 1 and capecitabine (XT) 1,500 mg/m(2) on days 1 through 14 every 3 weeks for four cycles followed by FEC for four cycles and stratified by timing of chemotherapy (preoperative v adjuvant). Accrual was stopped short of 930 patients on the basis of a Bayesian predictive calculation that additional accrual would be unlikely to change the qualitative comparison of the two regimens.

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