For Breast Cancer Awareness month we sat down with LifeScape physician Dr. Zoë McMillen for an intimate chat about risk factors, screenings, and steps we can take to help prevent breast cancer.

Are there certain risk factors associated with breast cancer?

There are both non-modifiable factors and modifiable factors associated with increased risks of breast cancer. 

Non-modifiable factors include:

• Increasing age (1 in 8 women)
• Female sex (100 times more frequent in women than men)
• Caucasian
• Tall stature
• Dense breast tissue
• Personal and family history of breast cancer
• Hormonal factors (both your own or additional estrogen with replacement)
• Earlier age to start or later end to periods

While it’s important to be aware of these factors, and stay on top of the appropriate screenings, there is nothing we can do to change them. 

We encourage patients to focus on the modifiable factors associated with increased breast cancer risk including:

• Hormone replacement therapy (estrogen) in postmenopausal women
• Weight and body fat (BMI >=30) in postmenopausal women
• Alcohol use
• Smoking
• Exposure to imaging such as CT scans of the chest at a young age
• Not carrying children
• Increasing age at first full-term pregnancy (ideally having your first child before the age of 35)

What steps do you recommend women take to help prevent or lower risks of breast cancer?

Moderation is everything! Maintain a healthy weight by limiting fats, proteins, and carbohydrates and maximizing whole, unprocessed foods.

Avoid toxins such as alcohol and nicotine (smoking). And while there is no conclusive evidence for certain chemicals studied showing a correlation to cancer, there are many that have not been studied, so in general, for overall health, I recommend avoiding additives/chemicals and doing our best to eat organic foods.

What screenings do you recommend, and what does LifeScape offer?

Always have a discussion first with your doctor. They will personalize the recommendations depending on your unique situation.

For example, you may need to start screening before you thought if you have a family history or a genetic risk factor. You may need genetic testing with a family history of breast cancer or other cancers, or if you have Ashkenazi Jewish ancestry. 

You may also need an MRI if you have very dense breasts or are at a higher risk of breast cancer. 

Mammograms now come with a calculation algorithm called the Tyrer-Cuzick risk assessment that calculates your 10-year or lifetime risk of developing breast cancer. If it is 15-20% you should talk with your doctor about screening MRIs, for > 20% an annual MRI screening is typically recommended together with mammograms. 

Regarding when to start screening, for average-risk women, we recommend having a discussion with your doctor about what is best for you. Many organizations have similar recommendations but there is some variance based on how each organization weighs the risks and benefits.

Shared decision-making is a process in which patients and physicians share information, express treatment preferences, and agree on a treatment plan. 

Are there any breast cancer misconceptions you’d like to address?

Some people believe there are associations with breast cancer that have not necessarily been proven. For example, there does not appear to be an association between abortion (spontaneous or other), caffeine, cosmetic breast implants, electromagnetic fields, electric blankets, and hair dyes with increased breast cancer risk. 

In addition, for women undergoing in vitro fertilization, there does not appear to be an increased long-term risk of breast cancer. 

There is mixed evidence for doctor or patient-performed breast exams, and some medical groups do not recommend it. In general, it seems only very high-quality physician-performed breast exams have any benefit.

Radiation from mammogram screening is not a huge concern. In 2015, a study¹ estimated the number of deaths due to radiation-induced cancer from annual screening over a lifetime with mammography was 0.016%, which is extremely low.

What does the evidence of “overdiagnosis” show us?

Just like with prostate cancer screening, there is evidence of “overdiagnosing”. Overdiagnosis is the detection of a disease by screening that would not have caused an issue or death if it had not been found. 

Systematic reviews (top type of research studies) estimate that 19% of breast cancers detected by screening represented overdiagnosis. 

Some cancers are slow-growing, and some even regress. An ideal screening test would distinguish between cancers that carry significant or minimal risk, but unfortunately, we do not have this type of technology available to us, meaning that treatment is nearly always recommended for a positive finding.

LifeScape’s health philosophy is focused on prevention, not just when it comes to breast cancer. Can you speak to this a bit? 

At LifeScape we focus on prevention. One of the biggest things we can do for overall health is maintain a healthy weight, eat well (all colors of the rainbow, feed our gut microbiome), stay active, and do everything in moderation. 

It is often said that our genes load the gun, but our environment pulls the trigger. 

It is definitely not a guarantee someone will get breast cancer even if they have a genetic mutation, but they are at higher risk. Lowering all other environmental risks is important. 

Any final thoughts you’d like to share with readers?

Unfortunately, breast cancer diagnoses are all too common! I have a patient who we recently diagnosed with breast cancer and are helping her to get established with the best breast specialists and expediting her genetic testing which can modify treatment plans. 

It is invaluable to have the peace of mind knowing that you have someone in your corner, fighting right alongside you.

1. Modeling report: Radiation-induced breast cancer and breast cancer death from mammography screening. Supporting document for U.S. Preventive Services Task Force; Breast cancer screening draft recommendations.