Mariana Chavez Chavez Mac Gregor

Prof. Dr. Mariana Chavez Chavez Mac Gregor

orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2016 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
ACAbigail S. Caudle
Abigail S. Caudle
WYWei T. Yang
Wei T. Yang
SKSavitri Krishnamurthy
Savitri Krishnamurthy
EMElizabeth A. Mittendorf
Elizabeth A. Mittendorf
DBDalliah M. Black
Dalliah M. Black
HKHenry M. Kuerer
Henry M. Kuerer
Purpose: Placing clips in nodes with biopsy-confirmed metastasis before initiating neoadjuvant therapy allows for evaluation of response in breast cancer. Our goal was to determine if pathologic changes in clipped nodes reflect the status of the nodal basin and if targeted axillary dissection (TAD), which includes sentinel lymph node dissection (SLND) and selective localization and removal of clipped nodes, improves the false-negative rate (FNR) compared with SLND alone.Methods: A prospective study of patients with biopsy-confirmed nodal metastases with a clip placed in the sampled node was performed. After neoadjuvant therapy, patients underwent axillary surgery and the pathology of the clipped node was compared with other nodes. Patients undergoing TAD had SLND and selective removal of the clipped node using iodine-125 seed localization. The FNR was determined in patients undergoing complete axillary lymphadenectomy (ALND).Results: Of 208 patients enrolled in this study, 191 underwent ALND, with residual disease identified in 120 (63%). The clipped node revealed metastases in 115 patients, resulting in an FNR of 4.2% (95% CI, 1.4 to 9.5) for the clipped node. In patients undergoing SLND and ALND (n = 118), the FNR was 10.1% (95% CI, 4.2 to 19.8), which included seven false-negative events in 69 patients with residual disease. Adding evaluation of the clipped node reduced the FNR to 1.4% (95% CI, 0.03 to 7.3; P = .03). The clipped node was not retrieved as an SLN in 23% (31 of 134) of patients, including six with negative SLNs but metastasis in the clipped node. TAD followed by ALND was performed in 85 patients, with an FNR of 2.0% (1 of 50; 95% CI, 0.05 to 10.7).Conclusion: Marking nodes with biopsy-confirmed metastatic disease allows for selective removal and improves pathologic evaluation for residual nodal disease after chemotherapy.

10 May 2014 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
MMMeena S. Moran
Meena S. Moran
SSStuart J. Schnitt
Stuart J. Schnitt
AGArmando E. Giuliano
Armando E. Giuliano
JHJay R. Harris
Jay R. Harris
SKSeema A. Khan
Seema A. Khan
MMMonica Morrow
Monica Morrow
Purpose: Controversy exists regarding the optimal margin width in breast-conserving surgery for invasive breast cancer. Methods: A multidisciplinary consensus panel used a meta-analysis of margin width and ipsilateral breast tumor recurrence (IBTR) from a systematic review of 33 studies including 28,162 patients as the primary evidence base for consensus. Results: Positive margins (ink on invasive carcinoma or ductal carcinoma in situ) are associated with a two-fold increase in the risk of IBTR compared with negative margins. This increased risk is not mitigated by favorable biology, endocrine therapy, or a radiation boost. More widely clear margins do not significantly decrease the rate of IBTR compared with no ink on tumor. There is no evidence that more widely clear margins reduce IBTR for young patients or for those with unfavorable biology, lobular cancers, or cancers with an extensive intraductal component. Conclusion: The use of no ink on tumor as the standard for an adequate margin in invasive cancer in the era of multidisciplinary therapy is associated with low rates of IBTR and has the potential to decrease re-excision rates, improve cosmetic outcomes, and decrease health care costs. J Clin Oncol 32. 2014 American Society of Clinical Oncology®, American Society for Radiation Oncology®, and Society of Surgical Oncology®. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without written permission by the American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology.

1 March 2014 in International Journal of Radiation Oncology, Biology, Physics
Verified
Journal Article
Closed access
MMMeena S. Moran
Meena S. Moran
SSStuart J. Schnitt
Stuart J. Schnitt
AGArmando E. Giuliano
Armando E. Giuliano
JHJay R. Harris
Jay R. Harris
Seema Ahsan KhanSeema Ahsan Khan
Seema Ahsan Khan
MMMonica Morrow
Monica Morrow

1 July 2011 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
AMAmal Melhem-Bertrandt
Amal Melhem-Bertrandt
MGMariana Chavez Chavez Mac Gregor
Mariana Chavez Chavez Mac Gregor
XLXiudong Lei
Xiudong Lei
EBErika N. Brown
Erika N. Brown
RLRichard T. Lee
Richard T. Lee
AGAna-Maria Gonzalez-Angulo
Ana-Maria Gonzalez-Angulo
Purpose: To examine the association between beta-blocker (BB) intake, pathologic complete response (pCR) rates, and survival outcomes in patients with breast cancer treated with neoadjuvant chemotherapy. Patients and Methods: We retrospectively reviewed 1,413 patients with breast cancer who received neoadjuvant chemotherapy between 1995 and 2007. Patients taking BBs at the start of neoadjuvant therapy were compared with patients with no BB intake. Rates of pCR between the groups were compared using a χ2 test. Cox proportional hazards models were fitted to determine the association between BB intake, relapse-free survival (RFS), and overall survival (OS). Results: Patients who used BBs (n = 102) were compared with patients (n = 1,311) who did not. Patients receiving BBs tended to be older and obese (P < .001). The proportion of pCR was not significantly different between the groups (P = .48). After adjustment for age, race, stage, grade, receptor status, lymphovascular invasion, body mass index, diabetes, hypertension, and angiotensin-converting enzyme inhibitor use, BB intake was associated with a significantly better RFS (hazard ratio [HR], 0.52; 95% CI, 0.31 to 0.88) but not OS (P = .09). Among patients with triple-negative breast cancer (TNBC; n = 377), BB intake was associated with improved RFS (HR, 0.30; 95% CI, 0.10 to 0.87;P = .027) but not OS (HR, 0.35; 95% CI, 0.12 to 1.00;P = .05). Conclusion: In this study, BB intake was associated with improved RFS in all patients with breast cancer and in patients with TNBC. Additional studies evaluating the potential benefits of beta-adrenergic blockade on breast cancer recurrence with a focus on TNBC are warranted.

1 March 2016 in JAMA Oncology
Verified
Journal Article
Open access
PDF file
MGMariana Chavez Chavez Mac Gregor
Mariana Chavez Chavez Mac Gregor
CCChristina A. Clarke
Christina A. Clarke
DLDaphne Y. Lichtensztajn
Daphne Y. Lichtensztajn
SGSharon H. Giordano
Sharon H. Giordano
In 2015, an estimated 231 840 cases of invasive breast cancer were diagnosed in the United States.1 Improvements in breast cancer treatment and early detection have resulted in a decrease in the mortality rates of patients with breast cancer in the last decades. Among patients with early-stage breast cancer, the use of adjuvant chemotherapy has had a dramatic effect decreasing the risk of recurrence and improving survival rates.2

10 February 2014 in Annals of Surgical Oncology
Verified
Journal Article
Closed access
PDF file
MMMeena S. Moran
Meena S. Moran
SSStuart J. Schnitt
Stuart J. Schnitt
AGArmando E. Giuliano
Armando E. Giuliano
JHJay R. Harris
Jay R. Harris
SKSeema A. Khan
Seema A. Khan
MMMonica Morrow
Monica Morrow