Investigating the Impacts of COVID-19 on Routine Breast Cancer Surveillance

Microscopic image of breast cancer cells - Generated with Google Gemini AI

The COVID-19 pandemic had a major influence on all areas of health care, and the scientific community is still investigating the effects on patients with cancer during this time. A retrospective cohort study investigated the impact of the COVID-19 pandemic on posttreatment surveillance for patients with breast cancer within a large healthcare system. Researchers compared patients diagnosed before and during the pandemic.

The study found a significant decrease in the proportion of patients receiving recommended annual breast imaging post-COVID compared with pre-COVID. Despite this decline in surveillance, the rate of breast cancer recurrence or progression was similar between the 2 groups. However, more follow-up is required to understand the implications of reduced surveillance on cancer outcomes.

Ultimately, the return of patients who have received treatment for breast cancer to their normal screening routines should be a priority for physicians.

“The importance of patient outreach really cannot be understated. The pandemic was so stressful and difficult for everyone. Now, in 2024, there is a way for patients to come back; health care systems can provide access and it is so critical for patients to have a way to return to normal screening and preventive care activities,” said Erin E. Hahn, PhD, MPH, first author of the study.

In an interview with Targeted Oncology^TM, Hahn, a research scientist at the Kaiser Permanente Southern California Department of Research & Evaluation, discussed the findings, implications, and next steps of this research.

Erin Hahn, PhD, MPH

Targeted Oncology: What would you consider to be the unmet needs that prompted this research?

Hahn: The scientific community has done a lot of work looking at the impact of COVID on cancer screenings. For patients who have not had cancer, who are in the general population, there was a big concern that COVID disrupted what we would normally see as typical screening patterns, andgenerally, what they found was that there was some disruption in regular cancer screenings. These screening delays may be associated with diagnosis at a later stage.

What I started thinking about was that we have patients who have already had cancer, and who have recommended screenings for cancer surveillance to catch recurrence or progression of their cancer. Was that disrupted by COVID? So, a slightly different population that really had not been looked at too much, because we needed some time to elapse to be able to have enough data.

What are the current recommended follow-up guidelines for patients who have had breast cancer?

For early-stage disease, which is what we focused in on, in this research and that is typically, stage 0, I, and II cancers, the recommendations from the National Comprehensive Cancer Network and the American Society of Clinical Oncology, they all include annual breast cancer screening for patients who have remaining breast. This is usually a mammography, or it could be a breast MRI in some cases. Also visits with their physician, making sure that a physical exam is conducted, and that a discussion of symptoms occurs. Those are the cornerstone recommendations for follow-up.

There is also a whole host of other types of things that can be discussed with a clinical team around depression, anxiety, and other cancer survivorship issues. In this study, we focused on recommended imaging for breast cancer surveillance.

What were the goals of the analysis and your methodology?

Here at Kaiser Permanente, we can access longitudinal data from our health records on many patients, which is wonderful for doing this type of research. We constructed a retrospective cohort study and defined 2 time periods for patients who had been diagnosed with early-stage breast cancer. We put together what we called a pre-COVID period, so this would include [patients] who were diagnosed between 2015 and the end of 2016. Then, we looked at their follow-up care through the end of 2019, before COVID began.Then, we had our post-COVID period. These [patients]were diagnosed before COVID, around 2018 to 2020, but their follow-up time was from 2020 to 2023 during the height of the COVID pandemic with lockdowns and other preventive measures. These are all patients that received curative surgery.

We looked at our electronic records to capture all posttreatment breast cancer screening that occurred in these periods. With Kaiser Permanente, we can see a complete picture of each patient because we can capture all Kaiser Permanente health care visits and tests as well as nearly all tests and visits to non-Kaiser Permanente facilities. Then, we did some modeling to determine if there were differences in proportions of patients screened in those 2 periods.

Can you summarize your findings?

We had about 3300 patients in our pre-COVID period and slightly more post-COVID, about 3900. The patients are similar when you look at things like their demographics, race, ethnicity, and age. What we found essentially isa significantly smaller proportion of these patients in the post-COVID group received the recommended surveillance screening within the first year after their treatment ended. When we looked at the first year, 85% of the pre-COVID group received their screening, and only 77% in the post-COVID group [received their screening]. This is a statistically significant difference between those groups. We also looked at their second year of surveillance, and here they came a little closer together, although the pre-COVID group was still higher, 83% vs 80% in the post-COVID group. What we are likely to see there is that the first year of COVID had an impact on getting those in-person services like mammography for cancer surveillance in these patients who have had breast cancer. 

We also looked at any difference in breast cancer recurrence or progression of disease that was diagnosed. Normally, we look at this in a 5- or 10-year timeframe. But we were curious to see, looking at these pre- and post-COVID groups, if there looks like there is any difference in the percentage of patients who had a diagnosed recurrence or progression. It was similar, as it turns out, about 2.5% in both groups.

Based on these findings, what would you consider to be the implications or the big takeaways for clinicians?

The important thing to take away here is the importance of tracking our patients and looking at these kinds of measures. There is a concern that a smaller proportion of patients received their recommended imaging in the post-COVID years, so there was this dip.The concern for clinicians is to make sure that your patients are coming back and that they are really interacting with you as a health care clinician, getting that annual screening, having those recommended visits with a clinician on your team, to make sure that we are not pushing off these recommended services. If delays in care for breast cancer surveillance persist, it is possible that recurrence or progression of disease would be caught much later. It is a similar message that we have seen in cancer screening in the general population. Now we need to ensure that outreach is occurring and good patient communication about recommended care is happening. If there are navigation services, any kind of outreach that can happen to these patients, that is key.

What do you see as the next steps from this research?

I think we will take another look at these data at the 5-year mark. Five years is our more traditional timeframe when we are looking at things like progression of cancer or recurrence. We will revisit these patients to see if COVID continued to have an impact on screenings, and if patients got back on schedule. We hope to see everyone getting their recommended care.

REFERENCE:

Hahn EE, Eng S, Chen A, et al. Impact of COVID-19 on post-treatment breast cancer surveillance and outcomes. J Clin Oncol. 2024;42(suppl 15):abstr e23114. doi: 10.1200/JCO.2024.42.16_suppl.e23114