Bolstering Access to Breast Cancer Screening for Genome Markers

The impact of performance status, age, and comorbidities on optimal treatment for patients with breast cancer is something that investigators have begun to address but needs more research to elucidate, according to Mariya Rozenblit, MD.

CancerNetwork® spoke with Rozenblit, medical oncologist and assistant professor of Medicine at the Yale School of Medicine, about key biomarkers or risk factors that might inform treatment decision-making for breast cancer, as well as strategies that may increase screening utilization and detection access for patients with actionable genome markers. She presented a subgroup analysis assessing immunotherapy and chemotherapy by tumor mutation burden (TMB) level while characterizing the prevalence of established actionable genomic markers at the 2024 San Antonio Breast Cancer Symposium (SABCS).

Rozenblit expressed that performance status, age, and comorbidities may dictate the preferred treatment regimen patients receive. To this end, she stated that patients with worse performance status, more comorbidities, and who are older may benefit more with immunotherapy than chemotherapy. She explained that her study began to explore this topic, but that further research was warranted to confirm these findings.

She then iterated that one of the biggest challenges to breast cancer screening utilization is financial, citing a need to increase its coverage and accessibility for patients. Furthermore, she emphasized increasing awareness of breast cancer screening and informing oncologists that testing for these markers is standard of care, particularly for patients experiencing disease progression on multiple lines of therapy. Rozenblit then explained that an additional biopsy may be necessary in cases where patients are progressing following multiple lines of therapy of therapy, given a propensity for cancers to mutate during treatment.

According to findings from the analysis study, patients who had a TMB level of 10 or greater receiving immunotherapy experienced a median progression-free survival [PFS] of 2.9 months vs 1.7 months in those with a TMB of less than 10 receiving immunotherapy (HR, 0.61; 95% CI, 0.39-0.95; P = .029). Furthermore, overall survival [OS] favored higher mutational levels for immunotherapy at a median of 12.9 months vs. 3.2 months, respectively (HR, 0.53; 95% CI, 0.32-0.88; P = .014).

Transcript:

Performance status is a big [factor], [as well as] age [and] what other comorbidities patients have. Patients who have a slightly worse performance status, or more comorbidities, or [who are] older might actually [benefit more] with immunotherapy than chemotherapy. That is something that we started to address in the poster but needs more research as well.

One of the biggest barriers [to screening] is financial. How can we make sure that [screening] is covered by insurance and easily accessible to all patients? The other one is spreading awareness and reminding oncologists that it is standard of care to test for these markers, especially as patients start to progress on different lines of therapy. Re-biopsying is a big one too. When possible, if a patient is progressing in second- or third-line settings, it is important to go back and re-biopsy and see if things have changed because the cancer sometimes mutates and develops. Whereas [before] they might not have had these biomarkers, they might now [have them] later on in their treatment course.

Reference

Rozenblit M, Quintanilha JCF, Ross JS, Levy M, Graf RP. Prevalence of actionable genomic alterations (GA) and predictive value of tumor mutational burden (TMB) for immune checkpoint inhibitor (ICI) effectiveness in HR(+)HER2(-) metastatic breast cancer (MBC). Presented at: 2024 San Antonio Breast Cancer Symposium. December 10-14, 2024. San Antonio, TX. P2-03-27.