Honesty is The Breast Policy: Are Breast Cancer Screening Tests Getting Inaccurate?

Overview of breast cancer

As you might have known, October is Breast Cancer Awareness Month! The entire month is devoted to raising awareness of breast cancer and its impact as an annual campaign. Breast cancer has been a prominent cause of death worldwide, responsible for 685,000 deaths of women globally as of 2020. It is also the world’s most prevalent cancer with 7.8 million women diagnosed with breast cancer between 2017 to 2022.

Breast cancer itself is characterized by the uncontrolled growth of breast cells. Different parts of the breast can become the starting point of breast cancer, including its main parts: lobules, ducts, and connective tissue. In most cases, breast cancers begin in the lobules or ducts. However, when it gets to the later stages, breast cancer can spread to other parts of the body through a process called metastasis.

Unlike cervical cancer or stomach cancer which results from infections, breast cancer does not have any infection-related causes. Therefore, there are so many factors contributing to the risk of breast cancer. The most common and strongest one is the female gender and age over 40. Other lifestyle aspects such as obesity, alcohol use, menstrual/pregnancy history, radiation exposure, family history of breast cancer, and so on may also increase the risk of breast cancer. However, good control of all these risk factors would only reduce the risk of breast cancer development by 30% maximum.

Why are breast cancer screening tests so important?

Just like cancers in general, breast cancer may appear unnoticeable until it reaches the more severe stages where the symptoms start to take place. Symptoms may appear as a new lump in the breast or armpit, swelling or thickening of part of the breast, discharge from the nipple other than breast milk, pain in any area of the breast, and more.

Therefore, it is important for women, especially those aged 50 to 74 years, to undergo screening tests for breast cancer. There are several types of breast cancer screening, including physical examination and history assessment, laboratory tests, imaging tests, and probably the most advanced one, genetic tests.

In a breast cancer genetic test, the breast cells or tissue are observed to detect any genetic or chromosomal changes. Biological specimens, such as saliva, blood, or buccal swab can also be collected and analyzed to identify a genetic mutation linked with breast cancer. As this examination is based on genetic analysis, it is generally conducted to determine any abnormalities in the “high penetrance” genes or genes playing a crucial role in breast cancer such as BRCA1, BRCA2, and PALB-2. Patients who are identified with mutations in those genes are highly recommended to undergo more procedures to further minimize their risk of getting (or worsening) breast cancer, such as breast removal.

In addition to that, there is also a method where the cumulative effect of “low penetrance” genes is studied, in an approach called “polygenic risk score”. Polygenic risk scores provide measurements of the risk of an individual getting a disease based on their genes. This approach can also be combined with other kinds of risk factors to further aid the patient in their disease progression and treatment response.

How accurate are breast cancer screening tests?

A study back in 2016 proved the inaccuracy of conventional breast cancer screening tests (especially mammography), which had a huge impact on the field of public health because a large population of women heavily relies on these types of tests to minimize their risk of breast cancer. When it comes to breast cancer screening (or any cancer screening in general), there are two main concerns:

1. Potential of over-diagnosing tumors that would not have become malignant
2. Chance of getting false-positive test results, along with the uneasiness of follow-up tests

In the past 10 years, the cancer research industry has witnessed numerous advancements in risk assessments and genetic testing for breast cancer. Through a thorough understanding of mutations in cancer-associated genes and patient-specific factors such as race, ethnicity, family history, etc., researchers are able to make breast cancer a more preventable and treatable disease. With the rapidly growing principle of personalization in healthcare, more studies are being conducted to make breast cancer screening more catered to each individual’s needs according to their risk factors and genetic makeup.

In honor of Breast Cancer Awareness Month, Nalagenetics thrives to contribute to breast cancer research in finding new ways to make its impact on society less severe. Currently, we are recruiting participants for our Breast Cancer Risk Prediction Score research project.  The study aims to observe the differences in chances of getting breast cancer based on genetic and non-genetic factors. Participants in this study will get free genetic testing for breast cancer while directly contributing to making the world free from breast cancer.

To find out more about our study, click on this link! Your participation will be of great appreciation.