Comini, Ana Carolina Marin

160 Background: In the United States, racial/ethnic disparities in adoption of breast cancer evidence-based practices (EBPs) persist along the cancer care continuum. This scoping review applied an implementation science lens to describe the current evidence base for interventions to reduce disparities, synthesizing evidence on effective interventions while highlighting gaps in the literature. Methods: A formalized search strategy identified USA-based interventional studies aiming to improve adoption of an EBP along the breast cancer care continuum among racially/ethnically minoritized patients. Relevant articles from 1/2010 - 8/2022 (Medline, Embase, Cochrane, and Scopus) were included. For each article, two reviewers screened and extracted data, with a third resolving discrepancies. The PRISMA-ScR checklist and JBO Manual for Evidence Synthesis framework were followed. Results: Our search strategy yielded 45,215 articles. After applying inclusion/exclusion criteria, 59 articles were retained, targeting screening (85%, 50 of 59), treatment (12%, 7 of 59), and survivorship (5%, 3 of 59) (2 targeted multiple areas). No articles targeted end-of-life care. Of these, 49% (29 of 59) were randomized controlled trials (RCTs). Among 24 screening RCTs, the most common interventions—and fraction with statistically significant improved screening uptake—were patient navigation (100%, 11 of 11) and patient education (80%, 4 of 5). Among 4 treatment RCTs, 3 targeted adjuvant chemotherapy uptake. Of these, 1 had significant improvements and used patient navigation. The 2 studies without significant improvements used a patient tracking tool/alert system or patient education. Among 2 survivorship RCTs, one used email interventions, resulting in significantly improved physical activity and dietary health. A second used a nurse-facilitated internet support group, resulting in significantly improved physical/psychological symptoms. Early to mid-stage implementation outcomes (acceptability, adoption, appropriateness, feasibility, or fidelity) were commonly measured (81%, 48 of 59). No study measured later stage implementation outcomes (sustainability or costs). Conclusions: In multiple studies, patient navigation and education improved breast cancer screening among racially/ethnically minoritized populations. In one study, patient navigation improved completion of adjuvant treatment. Despite these studies, patient navigation is not reimbursed for cancer screening, and adoption has not been widespread. Future studies should focus on evaluating and improving later stage implementation outcomes (sustainability and costs). Based on these results, insurance reimbursement mechanisms for screening-related navigation may be warranted. Future breast cancer care delivery disparities research should also be expanded to include treatment, survivorship, and end-of-life care.

Abstract Background Cyclin-dependent kinases (CDK) 4/6 inhibitors have significantly improved outcomes for patients with ER+/HER2− breast cancer. Nevertheless, they differ from each other in terms of chemical, biological, and pharmacological features, as well as toxicity profiles. We aim to determine whether QTc prolongation is caused by CDK4/6i in general or if it is associated with ribociclib only. Methods We systematically searched PubMed, Embase, and Cochrane Library for randomized controlled trials (RCTs) comparing the prevalence of QTc prolongation as an adverse event in HR+ breast cancer patients treated with CDK4/6i vs those without CDK4/6i. We pooled relative risk (RR) and mean difference (MD) with 95% confidence interval (CI) for the binary endpoint of QT prolongation. Results We included 14 RCTs comprising 16 196 patients, of whom 8576 underwent therapy with CDK4/6i. An increased risk of QTc prolongation was associated with the use of CDK4/6i (RR = 2.35, 95% CI = 1.67 to 3.29, P < .001; I2 = 44%). Subgroup analyses revealed a significant increase in the QTc interval for the ribociclib and palbociclib cohorts. The ribociclib subgroup showed a relative risk of 3.12 (95% CI = 2.09 to 4.65, P < .001; I2 = 12%), whereas the palbociclib subgroup had a relative risk of 1.51 (95% CI = 1.05 to 2.15, P = .025; I2 = 0%). Conclusion Palbociclib was associated with QTc prolongation; however, the relative risk for any grade QTc was quantitively twice with ribociclib. Furthermore, grade 3 QTc prolongations were observed exclusively with ribociclib. These results are important for guiding clinical decision-making and provide reassurance regarding the overall safety profile of this drug class.