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Credits

Physicians: .25 AMA PRA Category I Credits^TM

Family Physicians: .25 Prescribed credits

Nurse Practitioners: .25 Contact hours

Release Date: April 1, 2014

Expiration Date: April 1, 2015

Estimated Completion Time: 15 minutes

There is no fee for this activity.

To Receive Credit

In order to receive your certificate of participation, you should read the information about this activity, including the disclosure statements, review the entire activity, take the post-test, and complete the evaluation form. You may then follow the directions to print your certificate of participation. To begin, click the CME icon at the end of the article.

Program Overview

Learning Objectives

Upon successful completion of this educational program, the reader should be able to:

1. Discuss the significance of this article as it relates to your clinical practice.

2. Be able to apply this knowledge to your patient's diagnosis, treatment and management.

Faculty Information

Alan Ehrlich, MD - Assistant Clinical Professor in Family Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; Senior Deputy Editor, DynaMed, Ipswich, Massachusetts, USA

Michael Fleming, MD, FAAFP - Assistant Clinical Professor of Family Medicine and Comprehensive Care, LSU Health Science Center School of Medicine, Shreveport, Louisiana, USA; Assistant Clinical Professor of Family Medicine, Department of Family and Community Medicine, Tulane University Medical School, New Orleans, Louisiana, USA; Chief Medical Officer, Amedisys, Inc. & Antidote Education Company

Disclosures

Dr. Ehrlich, Dr. Fleming, DynaMed Editorial Team members, and the staff of Antidote Education Company have disclosed that they have no relevant financial relationships or conflicts of interest with commercial interests related directly or indirectly to this educational activity.

No commercial support has been received for this activity.

Accreditation Statements

ACCME: This activity has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education through the joint sponsorship of Antidote EducationCompany and EBSCO Publishing. Antidote is accredited by the ACCME to provide continuing medical education for physicians. Antidote Education Company designates this enduring activity for a maximum of 0.25 AMA PRA Category 1 Credits^TM. Physicians should only claim credit commensurate with the extent of their participation in the activity.

AAFP: Enduring Material activity, DynaMed EBM Focus, has been reviewed and is acceptable for up to 13 Prescribed credits by the American Academy of Family Physicians. AAFP certification begins March 7, 2012. Term of approval is for one year from this date with the option of yearly renewal. Each EBM Focus is worth .25 Prescribed credits. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

AANP: This program is approved for 0.25 contact hour of continuing education by the American Academy of Nurse Practitioners.

Program ID: 1304159T

Last week 567 journal articles were evaluated via DynaMed's Systematic Literature Surveillance and summaries of 217 articles were added to DynaMed content.

Based on criteria for selecting "articles most likely to change clinical practice," one article was selected by the DynaMed Editorial Team.

Anastrozole May Decrease Risk of Breast Cancer in High-Risk Postmenopausal Women
Reference: Lancet 2014 Mar 22;383(9922):1041 (level 2 [mid-level] evidence)

Breast cancer is the most common type of cancer affecting women, with more than 230,000 new cases estimated in the United States in 2013 (CA Cancer J Clin 2013 Jan;63(1):11). The United States Preventive Services Task Force (USPSTF) recommends that women at increased risk of breast cancer and low risk for adverse medication effects be offered tamoxifen 20 mg daily for 5 years or raloxifene 60 mg daily for 3-4 years to reduce their risk of breast cancer (USPSTF Grade B, Ann Intern Med 2013 Sep 24 early online full-text). This recommendation is partially based on a recent systematic review of 7 randomized trials showing that tamoxifen or raloxifene may reduce the incidence of invasive breast cancer by 7-9 cases per 1,000 women over 5 years compared with placebo (Ann Intern Med 2013 Apr 16;158(8):604). In addition, the MAP.3 trial recently showed that the aromatase inhibitor exemestane may reduce the incidence of invasive breast cancer among high-risk postmenopausal women (N Engl J Med 2011 Jun 23;364(25):2381 full-text). Now, a randomized trial compares anastrozole to placebo in 3,864 postmenopausal women aged 40-70 years at high risk of breast cancer.

Women were randomized to anastrozole 1 mg orally once daily vs. placebo. All women had at least 1 risk factor for breast cancer, including a first-degree relative with breast cancer, at least 2 second-degree relatives with breast cancer, at least 2 first- or second-degree relatives with ovarian cancer, prior atypical ductal or lobular hyperplasia in benign lesion, lobular carcinoma in situ, or prior estrogen receptor-positive ductal carcinoma in situ within previous 6 months and completion of adequate local treatment. At baseline, 47% of women were receiving hormone replacement therapy. All women had mammograms at least once every 2 years during median 5 years of follow-up. The 5-year adherence rate was 70% overall, and slightly lower with anastrozole vs. placebo (68% vs. 72%, p = 0.0047).

The incidence of breast cancer (either invasive cancer or noninvasive ductal carcinoma in situ) was 2% with anastrozole vs. 4% with placebo (p < 0.0001, NNT 50). Similarly, anastrozole was associated with a lower rate of invasive estrogen receptor-positive cancer (1% vs. 2%, p = 0.001, NNT 100), and ductal carcinoma in situ in (0.3% vs. 1%, p = 0.009, NNT 143), but there were no differences in invasive estrogen receptor-negative cancer (1% in each group) or mortality (1% in each group). The rate of non-breast cancer was 2% with anastrozole vs. 4% with placebo (p = 0.005, NNT 50). Hot flushes or night sweats occurred in 57% with anastrozole vs. 49% with placebo (p< 0.0001, NNH 12). Treatment discontinuation due to adverse events occurred in 20% with anastrozole vs. 15% with placebo (no p value reported).

This trial demonstrates that anastrozole is associated with modest reductions in the incidence of breast cancer among high-risk postmenopausal women. These results add another option in addition to selective estrogen receptor modulators tamoxifen and raloxifene and the aromatase inhibitor exemestane for prevention of breast cancer. However, none of these trials have yet shown a benefit for preventative therapy in breast-cancer related mortality or all-cause mortality. In light of this, the decision to offer such therapies for reducing the incidence of breast cancer in high-risk postmenopausal women must be carefully balanced by the potential for increased adverse events.

For more information see the Chemoprevention of breast cancer topic in DynaMed.

Earn CME Credit for reading this e-Newsletter. For more information on this educational activity, see the CME sidebar.

KidsCareEverywhere Blogging from Vietnam

EBSCO Information Services along with PEMSoft and DynaMed are proud sponsors of KidsCareEverywhere. KidsCareEverywhere is a public charity dedicated to transforming pediatric care in under-resourced communities by donating state-of-the-art medical software to public hospitals and training physicians and medical providers in software utilization.

Read about an ongoing initiative in Vietnam at KidsCareEverywhere

Call for Peer Reviews

We are currently seeking subspecialty reviewers for our Patient Education Resource Center (PERC). PERC provides fact sheets and discharge instructions for patients leaving the hospital or emergency room. These hand-outs fulfill the meaningful use requirements for the Medicare & Medicare Services Incentive Programs.

Click here to speak with us about becoming a peer reviewer.

DynaMed Careers

Looking for a change? The DynaMed editorial team is expanding and looking for talented and driven individuals. Visit the links below to learn about these exciting opportunities.

Deputy Editor of Oncology
Section Editor of Specialty Content

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