Short-Term Endocrine Pause for Pregnancy Safe in Early HR+ Breast Cancer

Halle Moore, MD, director of breast medical oncology in the Department of Hematology and Oncology at Cleveland Clinic Taussig Cancer Institute, discusses findings from a study on young breast cancer survivors who attempted pregnancy after interrupting hormone therapy.

The prospective POSITIVE study (NCT02308085) was designed to evaluate the safety of and pregnancy outcomes with interrupting endocrine therapy for patients with early-stage hormone receptor-positive breast cancer in order to attempt pregnancy. The primary end point was breast cancer-free interval.

Looking at the use of assisted reproductive technology in the POSITIVE study, experts explored pregnancy possibilities for young breast cancer survivors who paused hormone therapy to try conceiving. Results were ultimately promising with over 90% of patients regaining menstrual function after stopping treatment. Pregnancy rates were high, especially for younger women and those who banked embryos or eggs beforehand. Additionally, using ovarian stimulation for assisted reproduction, either before or during the study, did not seem to raise breast cancer recurrence risk within the 2-3 year follow-up period.

While these data are encouraging, longer-term research is needed to confirm these findings.

Transcription:

0:10 | One of the studies in which we were involved was looking at use of assisted reproductive technology in the POSITIVE study, which is a prospective trial that was designed to look at the safety of interrupting endocrine treatment for breast cancer in order to attempt pregnancy. In this analysis, we looked at the use of assisted reproductive technology, and breast cancer and pregnancy outcomes, as well as factors associated with recovery of menstrual function after treatment for breast cancer.

0:50 | In this cohort of young breast cancer survivors who interrupted their endocrine treatment to attempt pregnancy, we saw actually very high rates of menstrual function recovery. Just over half, we're not having periods at the time of enrollment, and after stopping their hormonal therapy, over 90% of those regained their menstrual function. Factors that were associated with slower recovery of menstrual function included chemotherapy, particularly if given without ovarian function protection with a GnRH analogue.

1:29 | Pregnancy rate was pretty high, and the likelihood was strongly influenced by age with younger patients, more likely to achieve pregnancy. It also looked like those who both stored embryos prior to or eggs prior to starting their cancer treatment and then, during the study period, using those embryos to achieve pregnancy, that group appeared to have the highest rate of becoming pregnant.

2:05 | Also very important, was the finding that the use of ovarian stimulation for assisted reproduction, whether it had been done at the time of their initial diagnosis, or whether it was done after enrollment on the study, as they were attempting to become pregnant, did not influence the risk of breast cancer recurrence. So now this is a relatively short-term follow-up, but in that follow-up period of 2 to 3 years, we did not observe an increase in breast cancer recurrence risk for those undergoing ovarian stimulation.