Breast cancer screening: Clinical sciences

Breast cancer is one of the most common cancers among biological females globally. Although mortality rates have decreased over time, the incidence of breast cancer continues to increase every year.

Because most patients remain symptom free until the late stages, breast cancer screening plays a major role in early detection and treatment of the disease, thereby increasing survival rates.

Breast cancer screening focuses on identifying high-risk patients and utilizing imaging like screening mammography or breast ultrasound to evaluate for a mass. The screening schedule and modality can differ based on the patient’s risk classification.

When a patient presents for breast cancer screening, your first step is to assess for risk factors that can contribute to the patient’s future development of breast cancer. The first screening should occur between the ages of 25 and 30 as a part of their primary care visit. The majority of risk factors can be obtained through a detailed health history.

Then, you can use a validated risk-prediction model to calculate the patient’s risk of developing breast cancer, like the Breast Cancer Risk Assessment Tool, also known as the Gail model; and the Tyrer-Cuzick model.

The Gail model calculates the estimated risk a patient has for developing breast cancer within the next 5 years, as well as their lifetime risk. It incorporates factors such as age; race and ethnicity; age at menarche; age at first live birth; age at menopause; history of breast cancer in a first-degree relative; and history of breast biopsies.

Similarly, the Tyrer-Cuzick model calculates a 10-year risk and incorporates factors like the patient’s age; body mass index, or BMI; age at menarche; parity; age at first live birth; age at menopause; history of hormone replacement therapy; breast density; BRCA mutation status; history of personal breast disease; Ashkenazi ethnicity; history of breast disease in a first-degree or second-degree relative; as well as a family history of ovarian cancer. Using these risk factors, the models calculate the likelihood, as a percentage, of developing breast cancer.

Now, patients with calculated risk greater than 20 percent are considered to be high-risk. For these patients, your next step is to assess their hereditary susceptibility. Patients who have a pathologic genetic mutation such as BRCA should have an annual MRI starting at age 25, and annual diagnostic mammography starting at age 30. In addition, consider offering a clinical breast exam.

On the other hand, patients who have a strong family history of malignancies should have annual diagnostic mammography starting at age 35, and possibly supplemental imaging with MRI and a clinical breast exam.

Any positive findings on imaging should be categorized according to the Breast Imaging-Reporting and Data Systems, or BI-RADS for short, which provides standardized interpretation, classification, and reporting of radiographic findings to determine the likelihood of malignancy. Decision-making and management is then planned in accordance with the BI-RADS findings.

Okay, before moving on to the remaining screening recommendations, let’s go through the BI-RADS guidelines. This guideline utilizes radiographic characteristics to categorize breast lesions into six categories based on their likelihood of malignancy.

Let’s start with BI-RADS 0. This classification indicates that the patient’s imaging information is incomplete based on the screening findings. In this situation, you might need to obtain additional imaging to evaluate further.