ESG Virtual Wellness Series
- Hereditary Aspect of Breast Cancer

Tharisini Soorianarayanan: Hi, thank you Fadyl for the very nice introduction. Hi everyone. My name is Tharasini and I’m a genetic counselor from Curie Genetics and from Curieoncology. So today I’ll be sharing the hereditary aspect of breast cancer. So today we’ll be talking about the hereditary aspect of breast cancer with the topic of lineage of breast cancer. So before we actually move on to our presentation, let me just put up this poll question that says “is breast cancer completely hereditary?” and we will see the answer in a short while. Okay. So this is just an introduction to breast cancer and breast anatomy as well. A woman’s breasts are fully developed when she’s in her twenties and this is affected by female hormones that vary during the menstrual cycle and a women’s reproductive period, which is between 20 and 40 years old. So the female breasts is made up of milk glands or lobes and ducts, and it’s surrounded by a layer of fat just as what we can see on the picture on the left. And breast cancer commonly develops within these milk ducts and as well as the lobes as well.

So this is just an overview of breast cancer in Singapore as of year 2020. So as we can see breast cancer accounts for 15.5%, which is the second highest among other cancers in Singapore, and it actually happens in both sexes, male and female, and it affects all ages. And this is about breast cancer in females, which accounts for the second highest as well. It’s about 32% and it’s among all ages as well. So around 1 in 15 women are affected by breast cancer in Singapore in their lifetime. And that’s why it is one of the highest cancers that runs in females.

So the second poll question, “if females can develop breast cancer, how about the males?” So this is just a question to test your knowledge, to see if males can also develop breast cancer. There are many factors that affect a woman’s predisposition to cancer, such as body weight, your BMI, diet, exercise, alcohol consumption, female hormones, as well as family history, which is going to be our main focus for today. So the inherited aspect of breast cancer has its own name, it is known as the HBOC or Hereditary Breast and Ovarian Cancer, which is a bit of a mouthful. So the first person that comes to our mind when we talk about HBOC is our very famous American actress, Angelina Jolie, and HBOC has also been frequently featured in US magazines, such as Newsweek and we can see here a family of three generation females were depicted to highlight the concept of HBOC.

So what is HBOC? As I explained earlier, it is an inherited genetic condition. So it means that the cancer risk is being passed from one generation to another generation in a family. So there are two primary genes that are linked with HBOC, which are known as the BRCA1 and BRCA2. So BRCA stands for Breast Cancer gene – it’s in short form. So every one of us, we have BRCA genes that protect ourselves from developing cancers. So usually someone who is predisposed to have HBOC related cancers when there is a mutation, it’s like a spelling mistake in a sentence, which is disease causing. And it can happen either in BRCA1 or BRCA2 and that puts a woman at an increased lifetime risk of developing breast and ovarian cancer.

So now we are back to poll question 2. So if you see whether a male can develop breast cancer, the answer is yes, because according to a study in Singapore in 2012, less than 1% of all breast cancer occurs in men. Over a 18 year period of study, they only got to know about 62 males that were diagnosed with breast cancer. And less than 110 to 20% of male breast cancers are due to the inherited faulty gene. So besides the male and female breast cancer, and as well as ovary cancer, as the name suggests, there are also some other related cancers such as pancreas, prostate for the male, and skin, which is also known as melanoma. 

So how do you know if a family is at risk for HBOC? So that is when one or more women are diagnosed with breast and ovarian cancer at age of 50 or younger. And when there is a notable family history of cancer, such as prostate, melanoma and pancreatic cancer as well. The other thing is that when a woman is diagnosed with a second breast cancer or she has cancer in both breast and ovary. And also there’s another hint when a male relative is diagnosed with breast cancer. So I need to emphasize that most women who have breast or ovarian cancer do not have HBOC. So this brings us to our very first poll question, “is breast cancer completely hereditary?” And the answer is no, because among all cancers, the hereditary aspect of cancers only account for 5% to 10%, as we can see in the picture that is being put up. So this is just to share a case study of this family.

This is Lianna and her family history. She’s a healthy 25 year old female and she’s very concerned about her family history of cancer. So as you can see, there is breast cancer in the family, there’s pancreas and there’s ovarian cancer as well. So she has two sisters, Maria and Ani, who are married. So they came for a genetic consultation to know more about their risk as well. So what happens during a genetic consultation is firstly, the pre-test counseling where it is crucial for us to obtain your detailed family history and to perform a risk assessment on it, followed by the genetic testing, which is mainly by the blood and saliva samples. Genetic testing is complex. So that is why it would not take place without a proper pre-test counseling and informed consent as well. So after both of these things are checked, that is when the post-test counseling takes place to review your genetic results. And also to see what are the action plans that are available if you’re tested positive.

Back to the case study. So Ani was tested positive for a mutation, which is in the BRCA1 gene and Liana tested negative for BRCA1. So now Liana can eradicate all the unnecessary testing and worries, but for Ani, there are available surveillances for her to take action on it. So these are some of the screening and surveillance options that are available. So such as your breast examination, be it clinical or self examination, your mammogram MRI of the breast and ultrasound of the breast, as well as transvaginal ultrasound with the cancer markers that is mainly for the ovaries. And besides the surveillance, are there also some preventative measures that can be taken such as what has been done by Angelina Jolie? So it is to remove your breasts, your ovaries, when you have finished your childbirth period. And there also is a method for chemo prevention.

Okay. So this is just a few checklist indicators of your life. Just like what Claudia has explained earlier. So there is some checklist to explain what you can do, what are some of the things that you can do during a lifetime. So if someone in their twenties is a fun time because young adulthood can be very fun, but that is when you know, someone is at physical peak as well. So it’s important for you to take action on good lifestyle, good eating habits and all the necessary health checkups. So the first few other breast examinations, like monthly examination and yearly clinical examination, if you have a family history and skin checks, if it’s necessary, pelvic exam and pap smear as well, other than to maintain a healthy weight, such as maintaining a healthy BMI, good eating habits and good lifestyle as well, which has been detailedly by Claudia earlier.

So the next is in the thirties. You don’t look much different from someone in their twenties, but your body is changing. So it’s important to also continue with all the surveillances, all the checkups, like your breast examination, pelvic examination, maintain a healthy weight, as well as establish good lifestyle habits. Besides that, if you are known to have a family history of cancers, it will also be worth it to go for a genetic counseling session to know your risk more. And the last is about the forties. When someone is in their forties, turning 40 is a milestone, and it’s a transition time because that is the time when someone will attain menopause in their late forties. So it’s really crucial to, again, follow up with all the checkups, your breast examination and when you can start your mammogram as well, your pelvic examination and pap smear. And the other additional one is your colonoscopy. Once every five years, if you have a family history of cancers, and that is for the general population as well, other than that it is to maintain a healthy BMI, your good eating habits and good lifestyle as well. And besides all this, I just want to reiterate that genetic counseling can be done as well at this age, if you’re concerned about a family history or you want to know about your risk assessment as well.

So we are at the last slide of the presentation. So I just would like to emphasize that knowledge is power and with all the medical advancement and technological advancement we have, I hope that you can grab this opportunity. That’s then something negative into something positive. And I hope that this talk will empower you to take all the necessary steps if you have a family history of cancer. This is our team from Curiegenetics, and I shall end my presentation here. Thank you.