TRANSCRIPT The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions. Guests on this podcast express their own opinions, experience, and conclusions. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement. Hello, and welcome to the ASCO Guidelines podcast series. My name is Shannon McKernin and today I'm interviewing Dr. Jennifer Griggs from the University of Michigan, senior author on "Adjuvant Endocrine Therapy for Women with Hormone Receptor Positive Breast Cancer: ASCO Clinical Practice Guideline Focused Update." Thank you for being here, Dr. Griggs. And thank you for the opportunity to talk about this focused update to the guidelines on extended adjuvant therapy. I would, of course, like to thank all my co-authors in the ASCO guidelines team for their contribution to this effort. So first, can you give us a general overview of what this guideline covers and their research which informed this focus update? Yes. First of all, the goal of the guideline was to give an update to the previous guidelines on this topic. And we specifically focused on extended adjuvant therapy. In particular, the aromatase inhibitors in women who had completed five years of adjuvant endocrine therapy. And it goes without saying, but it's worth reminding our listeners that the guideline is restricted only to post-menopausal women with hormone receptor-positive breast cancer. And, of course, our guidelines are only as good as the data upon which we rely. So for this guideline, six phase III randomized controlled trials met the pre-specified eligibility criteria for the updated systematic review and provide the evidence base for the guideline recommendations on the duration of aromatase inhibitor therapy. Each of the trials used the standard doses of the drugs that we use in practice today. So I'm not going to say the doses of each of the medications. So I'm going to go briefly over those six trials and just describe them so everybody's up to date with how the studies were designed. So briefly, the first trial I'll describe is MA17R, which compares letrozole to placebo for five years in over 1,900 women who had already received 4.5 to six years of adjuvant therapy with an AI, proceeded in most women by treatment with tamoxifen. The second study is NSABP B-42. And this also compares letrozole to placebo in nearly 4,000 women who'd completed five years of endocrine therapy with either five years of an aromatase inhibitor or up to three years of tamoxifen followed by an aromatase inhibitor, for a total of five years. The third study that we looked at is the DATA trial, which stands for the Different Durations of Adjuvant Anastrozole Therapy. This trial compared six years of adjuvant anastrozole with three years of adjuvant anastrozole in over 1,600 women after two to three years of adjuvant tamoxifen. The fourth trial out of the six is the IDEAL trial, the Investigation on the Duration of Extended Adjuvant Letrozole. This study randomized over 1,800 women to either 2 and 1/2 or five years of letrazole after five years of tamoxifen, an AI, or a combination in sequence of tamoxifen and an AI. So very similar study designs. The fifth study is the ABCSG-16 trial, the Austrian Breast Cancer Study Group Trial 16, which randomized nearly 3,500 women following four to six years of adjuvant therapy with tamoxifen and AI or a sequence of tamoxifen and then an AI, to either two or five years of anastrozole as extended therapy. And finally, the study of letrozole extension, or the SOLE trial, randomized over 4,800 women with node-positive breast cancer who had completed five years of adjuvant endocrine therapy to receive either continuous letrozole for five years or five years of an intermittent schedule of letrozole given nine months on and three months off in years