The POSITIVE trial is a clinical trial trying to answer an important question for patients that are survivors and cured of breast cancer. So we realised that survivors want to continue with their normal lives and reproductive issues are in this interest.

So the background of this study, we know that patients that had breast cancer and are free of disease five years after being treated for the cancer could have a pregnancy without an impact on the prognosis. But the POSITIVE trial is trying to answer the question if this could be done before and it’s testing the hypothesis of having a stop in the endocrine therapy for patients with hormone receptor positive breast cancer to have a parenthesis in the endocrine therapy to test if they can become pregnant.

The study design, it was an international prospective trial with one single arm. The inclusion criteria were women less than 42 years old that wanted to become pregnant after being treated for their breast cancer. All the patients had hormone receptor positive breast cancer and at least received 18 months of endocrine therapy and less than 30 months. In that situation, patients that wanted to become pregnant were included in the trial, had three months of washout period of the endocrine therapy and then started to try to become pregnant. The trial recommended a two year parenthesis of the endocrine therapy to become pregnant, have the delivery and breast feeding, if the patient wants to do that, and then the trial strongly recommended to continue the endocrine therapy until the end of the  planned treatment – up to five or ten years. The primary endpoint of the trial was the breast cancer free interval tested in those patients.

In the trial more than 500 patients were included in the trial and 497 patients were followed for pregnancy issues. The main result of the trial is that 47% of the patients had at least one pregnancy, 70% of those patients achieved that goal in the first two years, so in the planned two years in the analysis to become pregnant. 350 live births were the main result of the trial.

This clinical trial and the results of this trial may have a tremendous impact on how we could advise our patients regarding reproductive issues. One of the main limitations of the trial is the follow-up of the trial – at this moment it’s a follow-up of 41 months. So it’s a short follow-up period for this patient population but at least we do have this information to share with our patients when they come to the clinic and they tell us that they want to become pregnant. Before these results our advice should have been to stop or to wait until the five years until the end of the treatment for breast cancer. But now with these results we can share this data with our patients and, depending on their reproductive decisions and the age of the patient, we may consider a parenthesis in the endocrine therapy to become pregnant if this is the desire of the patient. We can explain to the patient and the family the pros and cons and we can share this data with all of them.