Season 1 - Episode 1

Helpful Links

For more information regarding the HERS Breast Cancer Foundation, please visit:

 ⁠https://hersbreastcancerfoundation.org/

Transcript

Introduction 

Hello everybody, welcome to mirroring medicine. My name is Kodi, your cohost alongside Isabel, the other co host. Since this month is breast cancer awareness month, today we will be talking about mechanisms of cancer, overview and statistics of breast cancer, risk factors, screenings, and treatment options. 

Biology of Cancer -

According to the NIH, cancer is the abnormal growth of cells which do not have the normal cell life-death cycle. Without this normal cell life-death cycle, cells which are “cancerous” begin to multiply and replicate without an apoptotic or stop sequence. So think of a wildfire, if you catch the wildfire when it is small, it could be stopped. However, when the wildfire gets too big and spreads, it might be too late to stop the wildfire without causing significant damage. The same thing goes with cancer. If you catch it through early diagnosis, there are medical interventions to stop it. However, if you do not catch the disease early enough, it might metastasize (which means spread throughout your body through the blood) causing other parts of the body to shut down. [7]

In this abnormal cell division also known as cancer, proto-oncogenes which are usually turned off, become mutated to become oncogenes and then start replicating by turning on. These genes allow for rapid replication of cells. However, there is another important type of gene which are tumor-suppressor genes. These genes help remedy this problem if there is an overgrowth of cells by producing these proteins and repairing/destroying these destructive cells. [7]

So how do cancers usually multiply and replicate? They do this by using an energy source. A cell’s specific energy source is ATP - adenosine triphosphate. This is produced in the mitochondria in which cancerous cells usually undergo anaerobic respiration. Anaerobic respiration is usually just glycolysis which produces 2 ATP per 1 glucose molecule. In normal cells, they undergo both anaerobic and aerobic respiration which includes the Krebs cycle and the electron transport chain. This produces a whopping 32-38 ATP molecules per glucose molecule. Anaerobic respiration in cancer does the longer way, but in doing so, it works behind the scenes. [7]

How is cancer usually studied? They use a person’s cancer cell line aka HeLa cells that were harvested off of Henrietta Lack’s body which are experimented on by researchers for this cancer researchers.

In summary, cancer in biology is through multiple gene mutations which lead to the upregulation of defective cells. This can be treated if seen early enough through routine visits to the doctors office or through screenings. [7]

Moving on I’ll pass it off to Isabel to discuss the type of cancer we are going to call to attention today. Without further adieu, 

Breast cancer is abnormal cell growth in the breasts, can occur in both men and women.

Types of Breast Cancer:

Angiosarcoma is a rare type of cancer that forms in the lining of the blood vessels and lymph vessels. Can occur in any part of the body, including the breasts. [2]

Ductal carcinoma in situ (early form of breast cancer), when cancer cells are confined inside a milk duct in the breast. Also known as stage 0 breast cancer. [2] - usually found during mammograms. 

Inflammatory breast cancer - growth of cancer cells in breast tissue, they break off breast tissue and block lymphatic vessels. Symptoms include swollen breast, red/purple color. [2]

Invasive lobular carcinoma - growth of cells in the milk-producing glands of the breast (lobules). [2] - very invasive type of breast cancer.

Male breast cancer- rare- cancer cell growth in breast tissue of men. [2]

Paget's disease of the breast - rare form of breast cancer. Starts on the nipple and extends to the areola.  around the nipple. [2]

Mayo Clinic, 2024

Incidence

• 1 in 8 women (13%) in the U.S. will develop invasive breast cancer at some point in their life [1]

• breast cancer incidence increased by 1% per year between 2012 and 2021.[1]

• 66% of breast cancer cases are diagnosed at a localized stage — before cancer has spread outside of the breast [1]

• BRCA1 mutation have up to a 72% lifetime risk of developing breast cancer. Women with a BRCA2 mutation have up to a 69% risk. [1]

Prevalence/groups most at risk

Black women have 5% lower breast cancer incidence than white women, but they have a 38% higher risk of dying from the disease. [1]

A woman’s risk of breast cancer nearly doubles if she has a first-degree relative (e.g. their mother, sister, or daughter) who has been diagnosed with breast cancer. [1]

• BRCA1 and BRCA2 associated hereditary breast and ovarian cancer syndrome (HBOC)

• Both BRCA1 and BRCA2 are genes that produce proteins that repair damaged DNA.

• Documented BRCA1 and BRCA2 pathogenic variants with increased risk of certain cancers, including breast cancer.

• Definitions:

• A pathogenic variant refers to a change or mutation in a gene that is known to cause disease or increase the risk of disease (NIH, 2023 - BRCA1- and BRCA2-Associated Hereditary Breast and Ovarian Cancer)

• Having a BRCA mutation means you have a likelihood of 45% to 85% for developing breast cancer in your lifetime, along with a 10% to 46% chance of ovarian cancer. (John Hopkins Medicine, 2024)

• BRCA1 and BRCA2 mutations follow an autosomal dominant inheritance pattern.

• Autosomal dominant is a pattern of inheritance in which a genetic trait or condition is passed down from a parent to a child when a single mutated gene is inherited from one parent. 

• BRCA1 - associated with increased risk of triple-negative breast cancer. Aggressive form of breast cancer.

• BRCA2 - elevates the risk of breast cancer in men, as compared to the BRCA1 mutation in men.

This podcast was inspired by the HERS Breast Cancer Foundation. This foundation aims to support all individuals healing from breast cancer by providing post-surgical products and services regardless of financial status. The foundation was founded in 1998, since then this organization has been providing post-operative care including personal fittings for products and services, appointment preferred Post-operative needs for partial and full mastectomies. This includes Specialty bras, wigs and much more. This foundation is bay area based and donation information will be provided. Click on the link to learn more.

• Reduce risk of breast cancer (Mayo Clinic, 2023)

• Reduce risk of cancer/other diseases

• Limit/reduce alcohol

• Healthy weight

• Exercise

• Quit smoking tobacco

• Breastfeeding (UK analysis NIH  Stordal 1)

• The risk of breast cancer is reduced by 4.3% for every 12 months of breastfeeding. 

• Breastfeeding reduces the risk of Triple‐Negative Breast Cancer (20%) and in carriers of BRCA1 mutations (22–55%). 

• The term triple-negative breast cancer refers to the fact that the cancer cells don’t have estrogen or progesterone receptors (ER or PR) and also don’t make any or too much of the protein called HER2. The cells test "negative" on all 3 tests.) (Cancer Society, 2024)

• Young age of first full‐term pregnancy (<25) reduces the risk of breast cancer in postmenopausal women by 35% compared to nulliparous women. 29 

• first birth occurred at age 25–29, women had an 11% increased risk compared to women who gave birth at <20 years. 28 

• When a first birth occurs at over 30 years there is a 24% increase in breast‐cancer risk. 28 

•  Women who had 3 or more children, with their first full‐term pregnancy after 25 years had a 106% increased breast‐cancer risk if they did not breast feed. 29 

• Research shows a correlation, however mechanism as to why breastfeeding causes decreased risk is not yet known only speculated on. 

• Perform self breast exams regularly

• Lump or skin changes

So what screenings are out there and when should we get them?

• Mammograms - x-rays of the chest (low radiation) [8]

• 3D mammograms (aka digital breast tomosynthesis) - costs more than 2d mammograms, less chance of being called back for missing something according to the ACS breast cancer screening website

• There is also a feel test - Clinical breast exam or the breast self exam. 

• When should you get them? [8]

• If you are a woman with “average risk” meaning that no history, BCRA gene mutation, or radiation of chest before 30 years old. 

• Woman between 40-44: can screen every year. 

• Woman 45-54: SHOULD get mammograms every year

• Woman 55+: Switch to mammogram every other year, or continue every year. 

• If you are a woman with high risk = breast MRI, starting age 30. [8]

• High risk = family history, BRCA1 or BRCA2 gene mutation, radiation therapy in chest before 30 y/o, or have li-Fraumeni syndrome, Cowden syndrome, or Bannayan-Riley-Ruvalcaba syndrome. 

• li-Fraumeni syndrome has abnormalities in tumor suppressor gene P53 on chromosome 17p13 [9]

• Cowden syndrome & Bannayan-Riley-Ruvalcaba syndrome are genetic disorders containing tumor-like growths aka hamartomas & increased risk of cancer. According to medline plus from NIH [10]

• What are the available treatments? [11]

• Mastectomy - removal of the entire breast through surgery. 

• Chemotherapy - anti-cancer medication/drugs given through the vein or mouth. 

• (In progress) = antibody drug conjugates.

Citations

1. American Cancer Society. “American Cancer Society Recommendations for the Early Detection of Breast Cancer.” American Cancer Society, ⁠www.cancer.org/cancer/types/breast-cancer/screening-tests-and-early-detection/american-cancer-society-recommendations-for-the-early-detection-of-breast-cancer.html⁠

2. Breastcancer.org. “Facts and Statistics.” Breastcancer.org, ⁠www.breastcancer.org/facts-statistics⁠

3. Gómez-López, Salvador, et al. “Breast Cancer: A Comprehensive Review.” PMC, vol. 15, no. 11, 2022, pp. 100-111, ⁠www.ncbi.nlm.nih.gov/pmc/articles/PMC9972148⁠

4. Johns Hopkins Medicine. “Inherited Cancer Risk: BRCA Mutation.” Johns Hopkins Medicine, ⁠www.hopkinsmedicine.org/health/conditions-and-diseases/breast-cancer/inherited-cancer-risk-brca-mutation⁠

5. Mayo Clinic. “Breast Cancer: Symptoms and Causes.” Mayo Clinic, ⁠www.mayoclinic.org/diseases-conditions/breast-cancer/symptoms-causes/syc-20352470⁠

6. Mayo Clinic. “Breast Cancer Prevention.” Mayo Clinic, ⁠www.mayoclinic.org/healthy-lifestyle/womens-health/in-depth/breast-cancer-prevention/art-20044676⁠