For premenopausal patients with early stage HR+ breast cancer for whom you are recommending tamoxifen, how do you select patients for extended endocrine therapy?

For women who remain premenopausal after 5 years of adjuvant tamoxifen, NCCN guidelines recommend "consider tamoxifen for an additional 5 years," or no further therapy.

I consider extended use in most of my patients who reach this point, as a combined analysis of the ATLAS and aTTom studies showed t...