Advances in Breast Cancer Screening and Surveillance

In the context of breast cancer, “screening” typically refers to looking for cancer in those without symptoms and at average risk, while “surveillance” or “monitoring” are terms often used for those with previously treated breast cancer or for individuals at very high risk of developing it. Recently, research has advanced in both these areas, providing new methods to detect cancer early, which opens new doors for treatment and improves outcomes.

Private Health Management (PHM) helps clients navigate these advances by developing individualized screening plans and personalized surveillance/monitoring strategies for our clients that are at higher risk. Here, PHM experts review personal risk, how imaging and blood tests may help detect recurrence earlier, and even how artificial intelligence (AI) is now starting to shape screening.

Breast cancer screening is not one size fits all

Mammography is the foundation of breast cancer screening, but recommendations vary based on individual risk. For standard risk individuals, it is typically recommended to begin screening at age 40 and to be screened either annually or every two years, depending on the organization (U.S. Preventive Services Task Force, American Cancer Society, and American College of Radiology). However, family and personal history, breast density, previous high-risk breast findings, inherited genetic variants, and radiation to the chest at a young age may support earlier screening or adding breast MRI to mammography. A summary of the general risk categories is below.^1–3

AI-assisted mammography screening may help detect more breast cancers earlier

AI is emerging as a promising tool to support radiologists as they read mammograms. It can flag areas that have subtle signs of potential cancer for closer review by the radiologist, and research suggests this may help find more cancers earlier. Indeed, in a trial of more than 105,000 women, AI-supported screening detected 29 percent more cancers than standard review without increasing false positives. And fewer cancers, including aggressive or advanced cancers, were found between scheduled mammograms.⁴ In another study, radiologists using AI detected 14 percent more cancers without more women being called back for additional testing.⁵ Although these findings are encouraging, they need to be confirmed across AI systems, patient populations, and breast densities.

The benefits and limitations of screening

When breast cancer is found before it spreads, it is far more likely to be curable.⁶ As such, mammography can reduce the risk of dying from breast cancer. But it does have limitations, including the potential to miss some cancers, produce false-positive results that require more testing, or detect slow-growing cancers that would not have caused harm. This is known as overdiagnosis.¹ Despite these limitations and downsides, screening remains the most valuable tool for early detection, especially when tailored to individual risk.

Advances in surveillance after treatment for early-stage breast cancer

For patients who have completed treatment for early-stage breast cancer, the plan of care shifts from active treatment to monitoring, where follow-up generally includes clinical visits, attention to new symptoms, and mammography when breast tissue remains,⁷ with the goal of identifying a recurrence earlier. This is often called “surveillance.”

Could imaging play a larger role in surveillance?

Guidance for surveillance is based largely on trials from the 1980s and 1990s, and at that time, it was found that intensive follow-up via imaging did not improve survival or quality of life.^8,9 This means that routine scans are generally not recommended for detecting distant recurrence in people without symptoms. However, with decades of improvements to imaging and treatment, researchers are reconsidering whether closer surveillance that utilizes modern technology, including more advanced CT, MRI, or PET scans, could allow for earlier intervention, and thus benefit some people.

A recent observational study from 2022 included 10,000 women with stage II or III breast cancer, and it found that detecting recurrence via imaging before symptoms developed was associated with a lower risk of death among those with the more aggressive breast cancer subtypes (triple-negative or HER2-positive).¹⁰ More research is needed to confirm these results, but the signal suggests newer treatments may be able to eliminate early metastatic recurrence in some cases, reinforcing the benefit of robust surveillance.

Can blood tests detect recurrence even earlier?

One promising newer approach to surveillance uses circulating tumor DNA (ctDNA), which consists of small fragments of DNA released by cancer cells into the bloodstream. Finding ctDNA after treatment may suggest that a small amount of cancer remains, even when no symptoms are present and scans show no evidence of disease. Across multiple studies, ctDNA was detected about 8 to 16 months before recurrence was identified through imaging or symptoms, indicating that the presence of ctDNA is strongly associated with recurrence.^11–15

Although ctDNA can predict recurrence, researchers have not yet shown that using these results to guide treatment improves outcomes. In one small trial, most people with a positive ctDNA test already had cancer visible on scans, and the study did not show a treatment benefit.¹⁶ Ongoing trials are studying whether earlier, more sensitive, or more frequent testing can provide a more useful window for intervention.

The advantages and drawbacks of advanced surveillance

Earlier detection of recurrence may allow time for additional testing, treatment planning, or participation in a clinical trial, but it can also create uncertainty when cancer is not yet visible, or no proven treatment is available. It may also lead to more scans and tests, which often increase costs, anxiety, and radiation exposure.^17,18 Ultimately, a personalized surveillance strategy must incorporate an individualized recurrence risk profile as well as a patient’s personal tolerance towards the negatives of close monitoring.

How PHM can help

PHM helps clients understand their breast cancer risk and determine whether additional imaging or genetic counseling may be helpful. For those with a history of breast cancer, PHM can also help develop an individualized surveillance plan and evaluate emerging tests or clinical trials in the context of current evidence and goals.