JCO Article Insights: Assisted Reproduction in Breast Cancer Patients

In this episode of JCO Article Insights, Dr. Giselle de Souza Carvalho interviews Dr. Hatem Azim and Dr. Ann partridge on their JCO article “Fertility Preservation and Assisted Reproduction in Patients With Breast Cancer Interrupting Adjuvant Endocrine Therapy to Attempt Pregnancy,”

TRANSCRIPT

Giselle Carvalho: Welcome to the JCO Article Insights episode for the August issue of the Journal of Clinical Oncology. This is Giselle Carvalho, your host. I'm a Medical Oncologist in Brazil focusing on breast cancer and melanoma skin cancers, and one of the ASCO editorial fellows at JCO this year. Today, I will have the opportunity to interview Dr. Hatem Azim and Dr. Ann Partridge, two of the authors of the POSITIVE trial. We will be discussing their trial on “Fertility Preservation and Assisted Reproduction in Patients With Breast Cancer Interrupting Adjuvant Endocrine Therapy to Attempt Pregnancy,” which was published in May this year. 

Hello, Dr. Azim and Dr. Partridge. Welcome to our podcast.

Dr. Ann Partridge: Hi. Thanks.

Dr. Hatem Azim: Hello.

Giselle Carvalho: So, beginning with our interview for breast cancer survivors, in addition to the treatment itself, aging is one of the major contributors to infertility. The optimal duration of adjuvant endocrine therapy in patients with hormone positive early breast cancer ranges from five to ten years, depending on patient and tumor characteristics. This time interval can be critical for women who wish to attempt pregnancy. One of the main concerns in daily breast cancer oncology practice is whether breast cancer recurrence rates are increased either by temporary interruption of endocrine therapy for pregnancy or by the use of assisted reproductive technologies.

Dr. Azim, what about assisted reproductive technology is worrisome regarding breast cancer outcomes? And how do the POSITIVE study results address the concern about worsening breast cancer outcomes either with assisted reproductive technology or endocrine therapy interruption?

Dr. Hatem Azim: So, in the primary analysis of the POSITIVE trial, we tried to address one of these questions, whether temporary interruption with endocrine therapy affects breast cancer outcome. And what we found was that interruption did not appear to have a detrimental impact at the median follow up of 41 months. So in the current manuscript, we addressed the second question, whether assisted production of fertility preservation has an impact as well on breast cancer outcome. And we did not find any worsening of outcomes in patients who underwent these procedures compared to those who had a spontaneous pregnancy. Of course, we have relatively short follow up, but at least the outcomes at the median follow up of around 3 to 4 years appears to be reassuring.

Giselle Carvalho: I see. Thank you. These are really important outcomes regarding premenopausal patients.

So, moving on, results from your study show that after 24 months, 80% of women under 35 years old had at least one successful pregnancy, while the same was true for 50% of women aged 40 to 42. These results are particularly impressive considering that over 60% of women over 35 had undergone chemotherapy. 

Dr. Partridge, other than age, what factors did you find were associated with a successful pregnancy? 

Dr. Ann Partridge: Yeah. The biggest factor, other than age, that was associated with successful live birth pregnancy was use of assisted reproductive technologies. So either having gone through IVF prior to diagnosis and banking eggs or embryos prior to diagnosis and then using them during the study, for undergoing stimulation of the ovaries during the study and then using it during the study. And that's what we also looked at in this most recent analysis of the initial POSITIVE data. 

Giselle Carvalho: I see. Thank you. The group of patients who underwent embryo oocyte cryopreservation at diagnosis were more likely to be nulliparous and treated with chemotherapy. Presumably these represent the patient group most afraid they will be infertile, as they would be receiving chemotherapy, and most desirous of pregnancy, as they had not yet had any children. Fertility preservation techniques are expensive and not easily available for all patients, particularly in less wealthy countries. Is there any group of your breast cancer patients with a high enough likelihood of pregnancy without assisted reproductive technology that you would not recommend this? 

Dr. Ann Partridge: Sure. So we are so glad to have assisted reproductive technologies available in many places, but as you know, they're not available everywhere. And even where they're available for some people, it's either inaccessible for a number of reasons or it doesn't feel right emotionally or ethically. And then finally, sometimes people need fairly quick treatment and they just don't have the time, even though we don't think there are long delays. And so we do and are able to know who can get pregnant after standard chemotherapy. Not perfectly, but we can give estimates. And the gestalt is, the younger a woman is, the less likely she is to become amenorrheic and the associated infertile, although it's not a perfect match in terms of amenorrhea being a surrogate. And then there are particular chemotherapy regimens that are more gonadotoxic than others. The more cyclophosphamide, for example, or alkylating agent, the more anthracycline, the higher the likelihood generally of causing at least amenorrhea and likely infertility. The huge caveat there is that for some of our newer therapies, we have no good information about how they might impact on menstrual status, let alone the actual rates of fertility. So we need to collect those data. But certainly, if someone's very young, they're going to get four cycles of TC or they have inflammatory breast cancer, we often take kind of a let the chips fall where they may approach, because they just aren't able to access it and we'll often do something like ovarian suppression through the chemotherapy to help support them and hope that it improves their menstrual functioning in the long run and/or fertility.

Giselle Carvalho: Thank you for your insight. So you found that pregnancy incidence over time differed by age group, although incidence of menstrual recovery over time was similar across all age groups, which I conclude that menstrual recovery does not translate into fertility. The addition of gonadotropin releasing hormone analogs to chemotherapy was not associated with time to pregnancy. However, of course, such use was not randomized. 

Dr. Azim, if assisted reproductive technology is not available to patients for reasons such as socioeconomic factors, would you recommend using GnRH analogs with chemotherapy for the purpose of fertility preservation? 

Dr. Hatem Azim: Yes. The short answer is yes. Of course, POSITIVE study was not designed to address the question around GnRH analogs, but we do have several randomized studies and meta analyses that have shown clearly that the use of GnRH analogs with chemotherapy reduce the risk of premature ovarian insufficiency. And subgroup analysis of some of these studies have shown a trend towards higher pregnancy rates as well. So, of course, if a patient does not have access to assist reproductive technology, GnRH analogs in combination with chemotherapy represent a very good alternative. 

Giselle Carvalho: I see. Thank you. Thank you for your response. At enrollment, 93.2% of women on POSITIVE trial had stage 1 or 2 disease and 66% had no negative disease. Therefore, one possible bias is that investigators might have been more comfortable with temporarily interrupting endocrine therapy if the risk of relapse was low.

Dr. Partridge, what recommendations would you have for women with stage three hormone receptor positive breast cancer who desire to attempt pregnancy?

Dr. Ann Partridge: Yeah, thank you. That's a really good question. It comes up in our tumor boards and discussions about patient care all the time, and I think, as you know, only a small proportion, about 6%, had stage 3 disease. Those patients are at higher risk of recurrence by nature of their stage. Not that all stage 3 are created equal, because, of course, if someone had a complete pathologic response to preoperative therapy and their stage 3 disease at diagnosis went to a PCR, then that person may have even better outcomes in the long run than someone who had postoperative treatment, and we don't know their likelihood even with stage 1 or 2 disease. But someone that you're concerned about their risk of recurrence, they still remain at risk of recurrence. And while we do not think, based on the POSITIVE data and all the data that we've had from retrospective studies and other data sets collected for other reasons, that a pregnancy would worsen their outcome, we certainly don't believe that a pregnancy at this point in time will dramatically improve their outcome or as a treatment for breast cancer. That's when I have a heart to heart conversation with the patient, really acknowledging they still remain at high risk. And most of my colleagues tend to want the patient to get more endocrine therapy into their system before they take a break. We've kind of discussed this, and we want someone to get more like at least three to five years. That may be a little bit paternalistic, because, as we know, taking the break for people with a little lower risk didn't seem to worsen outcomes. Maybe it's fine. I don't know that a break at five years is any better than a break at two years. I don't know. Hatem, how do you handle this in your practice?

 

Dr. Hatem Azim: Well, I completely agree with you, Ann. I mean, it's very much decided on a patient by patient basis. The level of uncertainty that some patients accept to take is not necessarily like others. And sometimes we as physicians, we adopt this. I agree with this paternalistic approach. Nevertheless, it's very important for the patient who is 32, is not necessarily counseled like the patient who’s 39, and her acceptance and the feasibility of waiting a bit longer as well in order to attempt pregnancy - the success of pregnancy afterwards is not necessarily the same. So I'm not sure we could adapt a one size fits all approach here. And I do not necessarily tend to factor much the elements around the stage. I think my point to patients is usually, well, you do have give and take this amount of risk of relapse, for example, and whether we accept to take such, what we could refer to as relatively unconventional approach of temporary interrupting endocrine therapy, and when we are comfortable to go ahead with this journey, depending on the feasibility of getting pregnant afterwards as well. So, yeah, I completely agree. It's very customized, based on and tailored according to the patients’ situation.

Giselle Carvalho: Thank you. I really appreciate your response to this. So, moving forward, tamoxifen alone was the most commonly prescribed endocrine therapy, followed by tamoxifen plus ovarian function suppression. The latter was preferred over aromatase inhibitors ovarian function suppression in the selected population. Endocrine therapy prescription changed in the second half of the recruitment period after July 2017 across all continents, likely due to the results of the SOFT and TEXT trials. It demonstrated absolute improvements in all disease outcomes by escalating endocrine therapy, which was more clinically meaningful in patients with high risk disease. Dr. Azim, how do you imagine this change could impact positive outcomes?

Dr. Hatem Azim: Honestly, I'm not necessarily sure that it impacts significantly the way you interpret the data and the way we counsel our patients. So, in our study, some 50% of patients received GnRH analogs and around 15% received AI. And most of the patients, I would say, were recruited in the second half of the study after we had the results from, for example, SOFT and TEXT. Furthermore, as we alluded to earlier, we had 60% of patients who received chemo. So most of our patients had a stage 1 and 2 disease in which you would argue that the absolute difference between the different hormonal therapy options is not necessarily massive. Whether or not this would impact much, I'm not sure. I think the main counseling recommendations would apply, that patients who receive endocrine therapy would be asked to interrupt it for at least three months and then they attempt pregnancy afterwards.

I don't know what you think, Anne, but I'm not sure that if we have more patients, and this is pretty much the case now, we have more patients treated with AI. I tend to do this a lot, especially if I'm thinking of interrupting, so I think I'm giving them maybe the best option first. I'm not sure this is necessarily, I mean, affecting me much, while interpreting that it does not appear that temporary interruption on the short term has an impact.

Dr. Ann Partridge: I completely agree with your strategy. Depending on the patient and their tolerance, if they have enough risk to warrant ovarian suppression with AI or tamoxifen, of course I recommend that. And yet, at the same time, I agree with you in this group that was in POSITIVE, I think the groups are relatively low enough risk. Although 40% had no positive disease, the majority got chemo, so they weren't that low risk. And so I think over time, these kinds of patients are more and more going to get ovarian suppression. I'm doing that more in my practice as tolerated. And I hope that all that means is that their breast cancer outcomes will be better independent of a pregnancy.

Giselle Carvalho: And on the topic of women with higher risk disease, CDK4/6 inhibitors are now used in the high risk adjuvant setting. How do you envision this impacting fertility?

Dr. Hatem Azim: Well, this is a very good question. Of course, this is something, this is an area of research that we have to address. Some analysis from some of the adjuvant studies, for example, the PENELOPE-B, I think they reported on some of the results of their study in which they were evaluating palbociclib in the adjuvant setting and did not appear that there was significant differences in terms of the level of estradiol levels and FSH and anti-Müllerian hormone, for example. I think these were the parameters that were evaluated in this study. So, of course, more information. Of course, palb is not the CDK4/6 inhibitor approved in the adjuvant setting. So we need more information as well about the other CDK4/6 inhibitors and longer follow-up. 

In my view from a counseling perspective, I think maybe you would have a certain level of uncertainty regarding whether or not this could have a mental impact on fertility. But the concept as well of possibly proposing a temporary interruption as we adopted in POSITIVE, would still apply. These patients would be treated as well, often, because if they are receiving CDK4/6 inhibitors in the adjuvant setting, it means that they have a high stage disease, so often they will be treated as well with GnRH analogs. I would counsel them pretty much the same, acknowledging a certain level of uncertainty regarding the data we have today on CDK4/6 inhibitors.

Dr. Ann Partridge: Yeah, if they got a full course, they would generally be further out than many people on POSITIVE, because we treat with, for example, the abemaciclib for two years and then you want to wash out and things like that. In POSITIVE, the average was two years. And so you'd expect people of higher risk to be a little further out, which I think would make everybody a little more comfortable too, because someone who's very high risk, you'd worry about very early bad recurrence, too.

Giselle Carvalho: Yeah. Thank you.

So, Dr. Partridge, regarding adherence to endocrine therapy resumption after the two year break, what was the percentage of patients who resumed treatment and which strategies would you suggest to increase adherence in this case?

Dr. Ann Partridge: That's a really great question. In the study, it was well over 70%, which is actually higher than you see in the general population of breast cancer survivors, especially young women. So in some cases, and I can tell you anecdotally, I experienced in my clinic that patients were more likely to start and take their endocrine therapy when they had the promise of the POSITIVE trial, to take a break to have a baby, because some of them don't want to start it, let alone stay on it, if they're told they have to take a full five to ten years. So it actually promoted adherence, ironically. And then for the people who got back on in the real world, the data suggests that by four years, somewhere close to half to 30% to half are no longer taking it. And so in POSITIVE it was, I think, 74% got back on, and that was only at the time point cut off when we did the initial primary data report. And of course more people will have gone back on because some people were still having babies and in the middle of things. And so I think that it's not as much of an issue with POSITIVE. In part, these are very compliant people, right? They're participating in a clinical trial to share the data with the rest of the world. They could have gotten pregnant on their own and they want to do it with their doctors. And so I think this is a little bit of a different group, but it was very reassuring to see that most people got on hormonal therapy after their interruption.

Giselle Carvalho: And recurrence of hormone receptor positive breast cancer may occur late. How long do you plan to follow patients enrolled in the POSITIVE trial?

Dr. Ann Partridge: So our plan is to follow them for at least 10 years. And it's interesting because we're starting to get close to that. We started enrollment in 2015, so I saw someone earlier this week who will have her 10 year mark next year because she got on in 2015. And that's very exciting. Obviously, it would be great to follow them even longer because ER positive breast cancer can recur many years later. But I do think that we feel as though at least 10 years will give us a good, very evidence-based feeling about the safety.

Giselle Carvalho: Thank you. Thanks for sharing. With enrollment occurring at 116 institutions in 20 countries across four continents, this representation of different races and ethnicities provides strength to support this recommendation for this group of patients worldwide.

Dr. Azim, what are your hopes for future analysis from this study and what future research in the area are you planning or would like to see performed? 

Dr. Hatem Azim: So Ann mentioned, of course, it would be crucial to conduct the long term follow up of these patients, and provide more reassuring evidence on the safety of this approach of adjuvant endocrine therapy. So this is something we're really looking forward to. Other analysis that we are working on is the breastfeeding analysis. So looking at patients who underwent breastfeeding and how far the feasibility of this approach, obviously, but how far as well this had an impact on their breast cancer outcome. So this is something that hopefully we are going to report on soon, expected end of this year. As well, we are working on evaluating, we had a large translation research program within POSITIVE, addressing several questions, including the evolution of ovarian function parameters over time and the ovarian reserve. Also, we are working on reporting on this information. We hope that this could happen maybe in the coming year.

Giselle Carvalho: Great. And finally, what advice do you give young women in your clinic who have been diagnosed with early stage hormone positive breast cancer and who are hoping to attempt pregnancy.

Dr. Hatem Azim: We address these kinds of questions relatively early in their treatments and often they are very much concerned about their chance of future fertility. Usually early on, for example, before going for chemo and so on, I just share the information that this is something that we certainly could discuss and certainly there are the possibility that we could consider in the future that it's not a ‘no go’ at least. And definitely it's something that we could work on once treatment is completed and recover from the adverse events of therapy. And because throughout the journey of treatments as well, women's wishes evolve over time and their perception of their pregnancy project as well evolve and change over time. So I think it's important to acknowledge, in my view, it's very important to acknowledge that this is feasible, this is possible, and because this as well provides an important psychological boost for them. And then as the patient comes over for their follow up after therapy and so on, start understanding, getting a little bit deeper into these kind of questions regarding feasibility, timing. If they are ER positive, then if it's okay to interrupt, not to interrupt, to explain a bit better and to consider a bit better regarding what kind of risk we're talking about. Articulating better, what do we mean by risk? So that sometimes you have a patient that is willing to accept a 10% risk, although others 1% risk for them represent a major threat. Also, it matters nulliparous versus a patient who already has two or three kids. So I think I tend to go a bit more granular in this kind of information as patients are out of chemo and on hormonal therapy and start addressing these matters. But I think it's important early on to share the information that nowadays we do have sufficient information not to discourage women who would like to have a pregnancy in the future.

Giselle Carvalho: Thank you. Thank you. Dr. Partridge, would you like to add some final comments on this?

Dr. Ann Partridge: Yeah, I think this is just such an important issue for our young breast cancer survivors and cancer survivors diagnosed at a young age, regardless of the type of cancer. So I think paying attention to this at diagnosis and through their survivorship is critical, both for their thriving in survivorship as well as for their long term health and cancer outcomes. Getting back to that adherence issue, people, if they're unhappy, won't do all the right things for themselves, sometimes medically and emotionally. And we know that infertility can be associated with long term distress for patients with and without cancer. So we need to pay attention to this and I'm really happy that ASCO is doing a podcast on this and I'm really happy that JCO is doing a podcast on this. 

Giselle Carvalho: Thank you. I really would like to thank you both, Dr. Azim and Dr. Partridge for attending this interview.

This is Giselle Carvalho. Thank you for listening to JCO Article Insights. Don't forget to give us a rating or review and be sure to subscribe so you never miss an episode. You can find all ASCO shows asco.org/podcast.

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. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity or therapy should not be construed as an ASCO endorsement.

 Dr. Azim
Employment Company name: Pierre Fabre, EMERGENCE THERAPEUTICS Stock and Other Ownership Interests Company name: Innate Pharma, Diaacurate Travel, Accommodations, Expenses Company name: Novartis

Dr. Partridge
Research Funding Company name: Novartis Patents, Royalties, Other Intellectual Property Company name: UpToDate