Certain individuals face a greater risk of developing breast cancer compared to the general population due to a family history of specific cancers. When a mother, sister, or daughter (first-degree relative) has been diagnosed with breast cancer, the risk of developing the disease approximately doubles. This risk increases further if more close relatives have had breast cancer or if a relative was diagnosed before the age of 50. However, it’s important to note that most women with a close relative who has had breast cancer will not develop the disease.
This article has been prepared in accordance with guidelines from the UK government for general practitioners. Its aim is to assist in the identification and guidance of individuals with an increased risk of cancer due to their family history.
Family History Breast Cancer Risk Assessment
If there is a family history of breast cancer, it’s important to consider undergoing a family history risk assessment. This assessment involves a comprehensive analysis of your family’s medical history to provide a personalized estimate of your susceptibility to developing breast cancer. Typically, the risk assessment is conducted at a specialized family history clinic or a regional genetics center, depending on your location. This thorough evaluation can provide valuable insights into your genetic predisposition to breast cancer, assisting you and your healthcare provider in making informed decisions about your health.
Referral to a Specialist
Your GP will suggest that you consult a specialist breast clinic or genetics clinic for evaluation if you exhibit any of the following:
– If you have a parent, sibling, or child who has been diagnosed with breast cancer before the age of 40.
– If you have a male first-degree relative who has been diagnosed with breast cancer at any age.
– If you have a first-degree relative who has had cancer in both breasts, with the first cancer diagnosed before the age of 50.
– If you have two first-degree relatives, or one first-degree and one second-degree relative, who have been diagnosed with breast cancer at any age. (Second-degree relatives encompass aunts, uncles, nieces, nephews, grandparents, and grandchildren.)
– If you have a first-degree or second-degree relative diagnosed with breast cancer at any age, as well as a first-degree or second-degree relative diagnosed with ovarian cancer at any age. (The first-degree relative could be any one of these..)
– If you have three first-degree or second-degree relatives diagnosed with breast cancer at any age.
Your GP should also refer you if you have a first-degree or second-degree relative diagnosed with breast cancer after the age of 40, coupled with one of the following conditions:
– If the cancer was present in both breasts (bilateral).
– If the cancer was detected in a male.
– If ovarian cancer was diagnosed.
– If you have Jewish ancestry.
– If a relative has sarcoma (cancer of the bone or soft tissue) and they are younger than 45 years.
– If a type of brain tumor named glioma or childhood adrenal cortical carcinomas were diagnosed.
– If you have complex patterns of multiple cancers diagnosed at a young age.
– If there are two or more relatives with breast cancer on your father’s side of the family.
Determining Breast Cancer Risk Level Based on Family History
Upon completion of your appointment, provided that your specialist team has gathered adequate information, you will receive an assessment of your risk level for breast cancer based on your family history. There are three distinct levels of risk for breast cancer.
General population risk (average or near population risk)
General population risk refers to the likelihood of developing breast cancer being similar to that of the general population. In the United Kingdom, one out of every seven women will experience breast cancer at some point in their lives. If a single family member has received a breast cancer diagnosis after turning 40, it is probable that you are at the same risk as the general population.
If you are considered to be at general population risk, you should receive information about regular breast screening. In the UK, women between the ages of 50 and their 71st birthday are offered a mammogram every three years. It is also crucial that you are informed about the significance of being vigilant about changes in your breasts and reporting any potential signs of breast cancer. It is important to revisit your GP if there are changes in your family history, such as the development of breast or ovarian cancer in another relative.
Moderate risk (familial or raised risk)
Individuals in this category face a higher risk of developing breast cancer compared to the general population. However, it is still more probable that they will not develop the disease, even with a family history of breast cancer.
Those at moderate risk may have multiple family members who have had breast cancer, but there is no clear pattern to the disease. While breast cancer may have impacted multiple generations of their family, it typically occurs at older ages. Additionally, someone may be considered at moderate risk if a close relative was diagnosed with breast cancer before the age of 40.
Individuals at moderate risk are typically offered regular breast screening. Women at moderate risk are offered screening from the age of 40, which is earlier than routine breast screening. In addition to screening, your specialist team may also explore the option of drug treatments to lower the risk of breast cancer. It’s crucial to consult your GP again if there are changes in your family history, such as the development of breast cancer or ovarian cancer in another relative.
High risk (hereditary or increased risk)
Individuals in this group have a higher likelihood of developing breast cancer compared to those at moderate risk. However, this does not guarantee that they will definitely develop the disease. Typically, those at high risk have a history of several close relatives on either their mother’s or father’s side being diagnosed with breast cancer, ovarian cancer, or both over multiple generations (e.g., grandmother, mother, and daughter). They are often diagnosed at a younger age, frequently under 50 years old.
If you are at a high risk, you will receive details about the available choices, such as breast screening and options for reducing the risk through surgery or medication. In contemporary medical, the precise identification and surgical removal of sentinel nodes pose minimal challenge or risk, thanks to advanced technologies like the gamma probe. This advanced technology allows for high-precision procedures, effectively minimizing the risk of cancer progression and recurrence. Additionally, Genetic counseling will be provided, and the potential for genetic testing will be addressed.
Breast Cancer Genes
If your family has a strong history of certain cancers, there may be a defective gen
e that increases your susceptibility to breast cancer. Several gene mutations are known to elevate the risk of breast cancer, and tests are available for some of them.
The genes BRCA1 and BRCA2 are known to heighten the risk of breast cancer. BRCA stands for BReast CAncer gene, and everyone possesses these genes. Their role is to prevent the uncontrolled growth and division of cells. However, if these genes carry a mutation, it can result in uncontrolled cell growth, potentially leading to the development of various cancers, including breast cancer.
Other genes that may elevate the risk of breast cancer due to mutations include TP53, PALB2, ATM, CHEK2, STK11, and PTEN. Having a mutation in any of these genes increases the likelihood of developing breast cancer, although it is not a certainty.
It’s important to note that most cases of breast cancer occur by chance. Researchers estimate that only about 5 to 10 out of 100 cases of breast cancer (5 to 10%) are caused by an inherited faulty gene.
Genetic Counseling for Family History Breast Cancer Screening
Individuals at high risk of developing breast cancer are typically offered a genetic counselling appointment at a regional genetics center. Genetic counselling may also be recommended for those with an unusual family history or when further investigation is needed to understand their risk. During the appointment, individuals will meet with a genetic counsellor or a clinical geneticist, who will provide specialized knowledge about genetics and inherited illnesses.
These professionals can help individuals comprehend their family history and the associated risk of developing breast cancer, as well as other cancers. They can also outline available options, such as genetic testing, mammogram screening ,drug treatments to reduce cancer risk, and surgery to mitigate the risk of developing cancer.
Given the emotional nature of discussing risk and its implications for oneself and loved ones, individuals may feel anxious. However, the genetics team has extensive experience in addressing these concerns and is able to provide the necessary support.
Conclusion
Family history significantly influences breast cancer screening practices. Individuals with a family history of breast cancer, particularly involving first-degree relatives, are often recommended to begin screening at an earlier age and undergo more frequent screenings compared to those with no family history. This is due to the increased risk associated with inherited genetic mutations, such as BRCA1 and BRCA2. Enhanced screening methods, including mammography, MRI, and genetic testing, are commonly utilized for early detection in high-risk individuals. By tailoring screening protocols to account for family history, healthcare providers can improve early detection rates and outcomes for those at elevated risk of breast cancer.
