O’Regan, Ruth

Importance The Breast Cancer Index (BCI) previously identified premenopausal patients with tumors in which the ratio of expression of HOXB13 relative to IL17BR (hereafter, BCI [H/I]–low tumors) as likely to derive greatest benefit from ovarian function suppression (OFS)–containing adjuvant therapy in the Suppression of Ovarian Function Trial (SOFT) trial. Objectives To assess BCI as a predictive biomarker of benefit from exemestane plus OFS vs tamoxifen plus OFS and to validate BCI as a prognostic biomarker for premenopausal patients. Design, Setting, and Participants This prognostic study used a prospective-retrospective translational design within the Tamoxifen and Exemestane (TEXT) and SOFT trials (enrolled November 2003 to April 2011). Blinded BCI testing in all available tumor samples was completed in March 2024. Premenopausal women with hormone receptor–positive breast cancer randomized to tamoxifen plus OFS or exemestane plus OFS who had BCI assessed were included. Analysis occurred from March to August 2024. Exposure 5 years of adjuvant tamoxifen plus OFS or exemestane plus OFS. Main Outcomes and Measures The primary outcomes were breast cancer-free interval (BCFI) for predictive analyses and distant recurrence-free interval (DRFI) for prognostic analyses after a median follow-up of 13 years in the TEXT cohort. Secondary objectives examined the predictive performance of BCI (H/I) in the combined TEXT and SOFT cohort overall and in prespecified clinical subgroups. Results Of 1782 patients in the TEXT study, 1034 (58.0%) had BCI (H/I)–low tumors; 915 (51.3%) of patients had N0 disease and 1077 (60.4%) were younger than 45 years. Patients with BCI (H/I)–low tumors had a 6.6% absolute benefit in 12-year BCFI (HR, 0.61; 95% CI, 0.44-0.85) for exemestane plus OFS vs tamoxifen plus OFS, while those with BCI (H/I)–high tumors had a 6.3% absolute benefit (HR, 0.78; 95% CI, 0.57-1.07; P for interaction = .29). Results were consistent in the combined TEXT plus SOFT cohort (2896 patients) and adjusting for clinicopathological variables. Clinical subgroup analyses consistently showed benefit of exemestane plus OFS vs tamoxifen plus OFS for BCI (H/I)–low tumors, and more variable relative treatment effects among BCI (H/I)–high tumors, including by age. Post hoc exploratory time-varying estimates suggested the treatment × BCI associations may differ in years 0 to 5 vs greater than 5 years. BCI and BCI N+ as continuous indices were prognostic for distant recurrence in N0 (HR, 1.27; 95% CI, 1.11-1.44; P < .001) and N1 (HR, 1.58; 95% CI, 1.21-2.05; P < .001) cancers. The 12-year DRFI was 96.3%, 90.3%, and 84.9% for BCI low-, intermediate-, and high-risk N0 cancers, respectively. Conclusions and Relevance In this study of premenopausal women with hormone receptor–positive breast cancer, BCI (H/I) status did not clearly predict greater benefit of adjuvant exemestane plus OFS vs tamoxifen plus OFS for women with BCI (H/I)–low tumors than for those with BCI (H/I)–high tumors; BCI continuous indices were reconfirmed as prognostic for premenopausal women. These findings support prior results of SOFT, which compared tamoxifen-alone vs OFS with either exemestane or tamoxifen, indicating premenopausal patients with BCI (H/I)–low tumors may benefit from more intensive endocrine therapy.

ImportanceAdjuvant ovarian function suppression (OFS) with oral endocrine therapy improves outcomes for premenopausal patients with hormone receptor–positive (HR+) breast cancer but adds adverse effects. A genomic biomarker for selecting patients most likely to benefit from OFS-based treatment is lacking.ObjectiveTo assess the predictive and prognostic performance of the Breast Cancer Index (BCI) for OFS benefit in premenopausal women with HR+ breast cancer.Design, Setting, and ParticipantsThis prospective-retrospective translational study used all available tumor tissue samples from female patients from the Suppression of Ovarian Function Trial (SOFT). These individuals were randomized to receive 5 years of adjuvant tamoxifen alone, tamoxifen plus OFS, or exemestane plus OFS. BCI testing was performed blinded to clinical data and outcome. The a priori hypothesis was that BCI HOXB13/IL17BR ratio (BCI[H/I])–high tumors would benefit more from OFS and high BCI portended poorer prognosis in this population. Settings spanned multiple centers internationally. Participants included premenopausal female patients with HR+ early breast cancer with specimens in the International Breast Cancer Study Group tumor repository available for RNA extraction. Data were collected from December 2003 to April 2021 and were analyzed from May 2022 to October 2022.Main Outcomes and MeasuresPrimary end points were breast cancer–free interval (BCFI) for the predictive analysis and distant recurrence-free interval (DRFI) for the prognostic analyses.ResultsTumor specimens were available for 1718 of the 3047 female patients in the SOFT intention-to-treat population. The 1687 patients (98.2%) who had specimens that yielded sufficient RNA for BCI testing represented the parent trial population. The median (IQR) follow-up time was 12 (10.5-13.4) years, and 512 patients (30.3%) were younger than 40 years. Tumors were BCI(H/I)-low for 972 patients (57.6%) and BCI(H/I)-high for 715 patients (42.4%). Patients with tumors classified as BCI(H/I)-low exhibited a 12-year absolute benefit in BCFI of 11.6% from exemestane plus OFS (hazard ratio [HR], 0.48 [95% CI, 0.33-0.71]) and an absolute benefit of 7.3% from tamoxifen plus OFS (HR, 0.69 [95% CI, 0.48-0.97]) relative to tamoxifen alone. In contrast, patients with BCI(H/I)-high tumors did not benefit from either exemestane plus OFS (absolute benefit, −0.4%; HR, 1.03 [95% CI, 0.70-1.53]; P for interaction = .006) or tamoxifen plus OFS (absolute benefit, −1.2%; HR, 1.05 [95% CI, 0.72-1.54]; P for interaction = .11) compared with tamoxifen alone. BCI continuous index was significantly prognostic in the N0 subgroup for DRFI (n = 1110; P = .004), with 12-year DRFI of 95.9%, 90.8%, and 86.3% in BCI low-risk, intermediate-risk, and high-risk N0 cancers, respectively.Conclusions and RelevanceIn this prospective-retrospective translational study of patients enrolled in SOFT, BCI was confirmed as prognostic in premenopausal women with HR+ breast cancer. The benefit from OFS-containing adjuvant endocrine therapy was greater for patients with BCI(H/I)-low tumors than BCI(H/I)-high tumors. BCI(H/I)-low status may identify premenopausal patients who are likely to benefit from this more intensive endocrine therapy.

Abstract Introduction: Triple-negative breast cancer (TNBC) presents unique challenges due to its aggressive nature and limited treatment options. Black women are disproportionately affected by TNBC, experiencing higher incidence rates and poorer outcomes compared to other racial/ethnic groups. This study aims to evaluate disparities in access to quality cancer care for Black women with TNBC from the perspective of oncology healthcare providers. Methods: From December 2022 to February 2023, the Association of Community Cancer Centers conducted a survey of 84 multidisciplinary care team members who provided care to Black patients with TNBC. The online survey captured quantitative and qualitative data on challenges related to accessing timely TNBC diagnosis and treatment services, care coordination for work-up and biomarker testing, confidence in TNBC treatment, clinical trial enrollment, supportive care services, and related referrals. Additionally, a follow-up focus group was conducted in May 2023 to further interpret select survey data, with a focus on shared decision-making, patient-provider communication, and ways to support cancer programs in improving screening, biomarker testing, and care coordination for individuals with TNBC. Results: Respondents reported several barriers to accessing timely diagnosis and treatment services for Black women with TNBC, including challenges in coordinating care for work-up and biomarker testing, providers' confidence in providing guideline-concordant comprehensive cancer care services for this patient population, enrolling patients in clinical trials, and making referrals for supportive care services. The survey revealed that community cancer programs treated an average of 21-50 patients with TNBC annually, with 31% of them being Black. Perceived patient-level factors contributing to challenges in accessing TNBC diagnosis and treatment included geographic distance to care facilities (14%), health literacy (18%), and insurance-related factors (21%). Practice-level barriers included limited accessibility of practice location (19%), capacity to accommodate new patients (27%), and insurance-related factors (34%). Additional findings highlighted slightly lower provider confidence in areas such as tobacco cessation (only 54% very confident), breast reconstruction (59% very confident), fertility counseling (52% very confident), and coordinating care across a fragmented healthcare system (52% very confident). Respondents identified the most commonly offered comprehensive cancer care services as palliative care (82%), nutrition support (77%), telemedicine (68%), psychological counseling (68%), and financial advocacy (68%). Less commonly offered services include recreational therapy (21%), legal aid (17%), and childcare (16%). Conclusion: This study highlighted the barriers faced by providers in delivering quality cancer care to Black women with TNBC. The findings underscore the importance of addressing challenges related to timely diagnosis and treatment services, care coordination, confidence in treatment options, clinical trial enrollment, and referrals for supportive care services. Insights from the focus group discussions further highlight the need for shared decision-making, improved patient-provider communication, and identification of opportunities to support cancer programs in addressing the specific needs of Black women with TNBC. To advance equity in cancer care, targeted interventions should focus on enhancing provider education, improving care coordination systems, and promoting cultural sensitivity. Efforts should also be made to overcome barriers related to limited accessibility of practice location, and insurance-related factors. By addressing these gaps, providers can play a crucial role in reducing disparities and improving outcomes for Black women with TNBC. Citation Format: Doreen Effange, Niharika Dixit, Ruth O'Regan, Ogori Kalu, Ryann Norcereto, Richard Simonds, Elizabeth Valencia, LaToya Bolds-Johnson, Aubrey Van Kirk Villalobos, Christie Mangir, Elana Plotkin, Karen Tacka, Leigh Boehmer. Evaluating Disparities in Access to Quality Cancer Care for Black Women with Triple Negative Breast Cancer in the US: A Provider Perspective [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-06-10.