How common is cancer during pregnancy and why is the incidence increasing?
The incidence is about 1-3% of all breast cancers. The incidence seems to be increasing due to women delaying their childbearing to when they are in their thirties. Breast cancer also seems to be increasing in women below 45 years.
What is the current treatment for cancer patients who are pregnant?
Currently we recommend treating them as closely as possible to standard recommendations for non-pregnant women. Surgery is no problem during pregnancy - even sentinel node biopsy can be performed if indicated. Chemotherapy can be given – anthracyclines, taxanes, cyclophosphamide are possible.
Endocrine therapies, e.g. tamoxifen cannot be given. Trastuzumab should be avoided and is not recommended. Radiotherapy should be delayed to after pregnancy.
Was chemotherapy during pregnancy previously thought to cause problems for the unborn baby?
It was never really clear, as all cytotoxic agents are listed as dangerous drugs. In the first trimester there is a high chance that cytotoxic agents as well as other drugs cause malformations. Well known is methotrexate.
Have babies previously been delivered preterm in order to deliver chemotherapy to the mother? Is this dangerous?
Preterm delivery in order to start chemotherapy was the current practice. But preterm deliveries, depending on the week of gestational age, can cause severe illnesses and deaths.
What did your research show?
Our research looked at how women cope with breast cancer during pregnancy. Chemotherapy is given in more than 50% of the patients. The regimen is comparable to those in non-pregnant women. Also taxanes can be given.
We showed clearly that the newborns have a lower birth weight, which usually has no clinical implication. There were more events of the infants documented in the group which received chemotherapy during pregnancy but still the majority was attributed to preterm deliveries.
One has to be careful because it is a registry and events in the group of infants not exposed to chemotherapy might be underreported.
What do you think is the reason why mothers who had undergone chemotherapy while pregnant had, on average, a baby with a lower birth weight?
I can only hypothesize:
- first the chemotherapy can affect the placenta and it is cause by placenta insufficiency
- second it could be due to stress cause by the whole situation
What factors do pregnant women need to consider when deciding whether or not to have chemotherapy?
The vast majority of young women with breast cancer will need chemotherapy as part of their standard treatment. Delaying chemotherapy can have an implication on survival.
If one cannot wait due to different reasons (e.g. large tumors, aggressive biology of the tumor), chemotherapy should be started during pregnancy. Or if a neoadjuvant therapy would be the preferred option, chemotherapy should be started within 2-3 weeks.
The patient needs to be informed thoroughly and should be treated within an experienced multidisciplinary team.
At the end of the day it is always an individual’s decision.
How do you think the future of cancer treatment for pregnant women will develop?
I hope that there will be no more unnecessary terminations of the pregnancy and preterm deliveries without a real medical indication.
Chemotherapy will be considered as a possibility in pregnant breast cancer women also as neoadjuvant approach.
New treatment options will come up and need to be integrated into the treatment algorithm for pregnant women.
Do you have any plans for further research into this field?
The registry will be continued to collect more data and more long term data. We will further collect tumor material to perform translational research. We will also elaborate on the outcome of the treated with different therapies for breast cancer during pregnancy.
Would you like to make any further comments?
I would like to thank all patients and colleagues who contributed to the registry. The independent BANSS foundation as well as the German Breast Group made this research possible.
Many more should contribute to this registry and this joint effort with our colleagues from Leuven is the right way to continue and conduct research in orphan diseases.
Where can readers find more information?
www.germanbreastgroup.de and www.ago-online.de (recommendations available in German and English)
About Professor Sibylle Loibl
Prof. Sibylle Loibl, MD, PhD is leading the Department of Medicine and Research and she is a member of the management board at the German Breast Group (GBG) an academic Research Institute. Department of Medicine and Research contains the medical counselling, medical writing, translational research, statistics´ department, data management, and software engineering.
Prof. Loibl is an assistant Professor at the University of Frankfurt and offers a clinic once a week for adjuvant and metastatic breast cancer with a focus on neoadjuvant therapy; young women and pregnancy related breast cancer as well as fertility counselling.
Her scientific focus lays on the field of breast cancer in particular the field of breast cancer in pregnancy with national as well as international reputations.
She has developed the translational research part within the GBG and is currently leading an EU-FP-7 project.
Prof. Loibl received her medical education at the University of Heidelberg and completed her fellowship and residency at the Women’s Hospital, University of Heidelberg, and the Women’s Hospital, University of Frankfurt, Germany.
She has participated and led a large number of national and international clinical trials. In cooperation with Professor von Minckwitz she has contributed to the improvement of the infrastructure for breast cancer trials all over Germany.
Prof. Loibl has authored and co-authored 125 medline listed scientific papers, in addition to more than 175 original and peer-reviewed articles as well as 29 books or book chapters and she has actively contributed to more than 157 national and international congresses.
Prof. Loibl is an active member of the ASCO, EORTC-TRAFO, ESGO as well as Commission „Mamma“of the AGO (“Arbeitsgemeinschaft Gynäkologische Onkologie”), DKG (German Cancer Society) and DGGG (German Gynecologists´ Society).