SABCS 2022 | POSITIVE: global study to support young survivors of HR+ BC who desire pregnancy

The POSITIVE trial was a study designed to answer a clinical dilemma facing our young patients. Many young women when they’re diagnosed with breast cancer have hormone receptor-positive breast cancer, and part of routine treatment to optimize their breast cancer outcomes, is adjuvant endocrine therapy, which entails five to 10 years of treatment. During that time, a pregnancy is either not feasible or contraindicated because those drugs either make someone not able to get pregnant or they can cause birth defects. And so, young women, when diagnosed with often a very curable early-stage breast cancer, are facing this issue of, “I want the best breast cancer care.” And at the same time, “I didn’t finish my family,” or, “I haven’t started my family and I want a biologic child.”

So, this study was designed to address this problem and we enrolled a cohort of women and put them through, because they wanted to have a pregnancy and a baby, we enrolled them and put them through a protocol where they had to have taken at least 18 to 30 months of endocrine therapy and then desired a pregnancy, and were willing to take a break from endocrine therapy in order to try to have a pregnancy and carry the pregnancy.

We enrolled 516 women, and we followed them over time at a median follow-up of about 41 months. We found that the most important thing, which was how safe was it? What were their relapse rates? Their relapse rates were very similar to a well calculated control group from a prior study of similar patient population. So, similarly low, not zero, but similarly low, and that included distant relapse rates or coming back elsewhere in the body.

These are very reassuring data. It’s important to note that they’re pretty short-term. These are women who are about five years out from their breast cancer and with hormone receptor positive breast cancer, there is a risk of later recurrence, and so we need to follow these women long-term. The other really important finding from the POSITIVE trial was that the majority of women actually were able to get pregnant, sometimes using assisted reproductive technology, and most of those women had live babies. So, hese data are, I think, really important and reassuring for patients, their families, and the doctors and other healthcare providers who care for them, to help them to make decisions in this kind of vulnerable place of trying to survive, but thrive after a cancer diagnosis.