How can having a BRCA1/2 mutation impact my fertility?
It seems like the running list of things that can impact someone’s fertility does not stop. Usually, the list contains environmental toxins like pesticides and BPA. However, there can be genetic impacts to fertility as well. In this blog post, we will discuss additional considerations that can be made for individuals who have been diagnosed with a cancer predisposition syndrome, specifically Hereditary Breast and Ovarian Cancer (HBOC) syndrome.
What is Hereditary Breast and Ovarian Cancer (HBOC) syndrome?
Hereditary Breast and Ovarian Cancer (HBOC) syndrome is a genetic condition caused by changes in either the BRCA1 or BRCA2 gene. When someone has a change in one of these genes, then the gene is not able to carry out its intended function which is tumor suppression. Someone with HBOC has a higher risk than the average person to develop certain cancers because their BRCA1 or BRCA2 gene is not able to prevent tumor formation into a cancer. These cancers include breast, ovarian, prostate, pancreatic, and skin.
There are other cancer predisposition syndromes that also can increase the risk of someone developing certain cancer like Lynch syndrome. This post focuses on HBOC, but many of the below points are applicable to other cancer predisposition syndromes. By having a cancer predisposition syndrome, it does not mean the person will develop cancer. Monitoring and treatment is typically available to decrease the chances of developing cancer.
What are the treatment options for HBOC?
There are a few treatment options such as increased surveillance or prophylactic surgery/preventative surgery. Surveillance means the person is getting screened for cancer. Everyone has the option to be surveilled for cancers and often it is at no or low cost for the general population as it is considered “preventative care”. For someone with HBOC, however, they typically have their screening performed earlier and more frequent than the general population. For example, to check for breast cancer, a person may have a mammogram every year as well as a breast MRI (magnetic resonance imaging).
The intention of prophylactic surgery is to remove the organ that has the increased chance to develop cancer prior to developing cancer. For HBOC, there is usually an increased risk for breast and ovarian cancer. By removing these organs completed, the risk can be reduced.
How Can Treatment Impact Fertility?
If someone chooses to under prophylactic surgery of their reproductive organs (breast and ovaries), then reproductive options change. If prophylactic oophorectomy is chosen (which is the removal of the ovaries), then the person would not be able to conceive a child that shares their genetics given the ovaries produces egg cells. If someone chooses to undergo prophylactic mastectomy, then the ability to breastfeed is no longer an option. These procedures are done to substantially decrease the person’s risk for cancer in that organ system. Another way treatment can impact fertility is if someone develops cancer and has radiation or chemotherapy performed. Radiation and chemotherapy can damage the person’s sperm or egg cells.
What Options Does Someone Have to Preserve Their Fertility?
There are a few options that anyone from the above scenarios can consider if they plan to have children in the future. One option is to retrieve the person’s sperm or egg cells. For sperm, there is the option to collect a semen sample and cryopreserve or freeze the sample at a clinic. For egg cells, there are a few extra steps including hormonal treatment to mature as many egg cells as possible and then retrieval from the ovaries. This process is similar to the beginning steps of in vitro fertilization. The egg cells are then cryopreserved at a clinic. The person can have the option to keep the sperm or egg cells cryopreserved or to first make embryos with a current partner or sperm/egg donor and then freeze the embryos.
Another role assisted reproductive technology can play in the setting of HBOC or other cancer predisposition syndromes is by the use of in vitro fertilization (IVF) with preimplantation genetic testing for monogenic conditions (PGT-M). Someone with a genetic change in one of their BRCA1 or BRCA2 genes has a 50% to pass that gene to their embryos/children.
PGT-M with IVF is the ability to make embryos and test them for the cancer predisposition syndrome. For the embryos that do not have the cancer predisposition syndrome, they are then transferred into the uterus of the person who plans to carry the pregnancy. This option allows for the ability to reduce the chance that future children inherit the syndrome. For some, the 50% chance of passing it down makes them want to utilize PGT-M to avoid conceiving a pregnancy with the syndrome whereas others feel that while it would be nice to know that information, it doesn’t change their reproductive plans.
There is also the option for people to use donor egg or sperm from someone who does not have a cancer predisposition syndrome or they can choose adoption. Ultimately, it is important to have this discussion with a healthcare provider regarding the treatment course and recommendations in order to know what aligns best with someone’s values and health. Oncofertility is an emerging field with specialists ready to have this conversation.
Resources:
BRCA1/2 GeneReviews: Petrucelli N, Daly MB, Pal T. BRCA1- and BRCA2-Associated Hereditary Breast and Ovarian Cancer. 1998 Sep 4 [Updated 2022 May 26]. In: Adam MP, Everman DB, Mirzaa GM, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2022. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1247/
National Comprehensive Cancer Guidelines: https://jnccn.org/view/journals/jnccn/19/1/article-p77.xml#:~:text=The%20NCCN%20Guidelines%20Panel%20recommends,pathogenic%20or%20likely%20pathogenic%20variant.
http://www.jscholaronline.org/articles/JWHG/Caring-for-BRCA-Carriers.pdf
IVF to Prevent Passing on BRCA – The Other Side of the Story
Facing Our Risk: https://www.facingourrisk.org/
Basser Center for BRCA: https://www.basser.org/support-and-resources
* This blog constitutes general information about genetic testing and medical screening. This blog does not offer or provide medical advice or diagnosis, and nothing in this blog should be construed as medical advice or diagnosis. Do not rely on the information in this blog/article to make medical management decisions. Please consult with a medical professional before making those decisions. Do not delay in seeking professional medical advice if you think you have a medical concern. Do not disregard professional medical advice based on any information received in this blog.
