Background: It is of value to determine whether treatment disparities exist in the management of hormone receptor positive (HR+), HER2 negative (HER2-) MBC due to location, age, gender, practice type, or payment methods. The objective of this study was to evaluate prescription patterns for CDK46 inhibitors (CDKI) in the first line setting in patients with HR+ HER2- MBC at the University of Pittsburgh Medical Center (UPMC), a tertiary care academic center with a large satellite clinic network. Methods: Data were obtained using a quality care insight tool (QCIT, Pfizer) which provided information regarding MBC treatment utilization patterns using the pharmacy and medical claims data from the IQVIA Anonymized Patient Longitudinal Dataset. This data set includes HIPAA-compliant anonymized information on diagnostic codes, tests, prescribed treatments, and procedures for 17.9 million US cancer patients from 2012 onward. Analysis was focused on a comparison of a UPMC patient cohort to a national cohort of patients with HR+/HER2- MBC to better understand local prescription patterns. Inferential statistical analysis was not applicable to data obtained from the QCIT tool and thus was not performed. Inclusion criteria included (1) patients ≥ 18 years of age on first breast cancer occurrence; (2) medical claim indicating HR+ breast cancer and the absence of HER2 positivity; and/or (3) a pharmacy claim for a CDKI; and (4) at least one medical or pharmacy claim six months before and six months after MBC diagnosis and CDKI prescription. Results: Comparison of national treatment prescription patterns to treatments utilized at UPMC facilities for patients with HR+ HER2- MBC in the first-line setting demonstrated higher rates of CDKI-based therapy utilization within UPMC institutions comparatively (61% vs. 54%, respectively). Rates of chemotherapy use in the UPMC population were concordantly lower than the national average (1% vs. 5%). The rate of CDKI-based therapy utilization in MBC patients in the first line was higher at urban UPMC sites vs. their rural counterparts (82% vs. 70%). Patients with Medicare showed notably lower CDKI utilization rates compared to their counterparts receiving Medicaid (43% vs 83%) or commercial third-party insurance (43% vs. 63%). Conclusions: Higher rates of CDKI utilization in the first-line metastatic setting indicate more widespread adoption of first line CDKI at UPMC (a tertiary health care system with a large community satellite network) as compared to national averages. Within the UPMC patient population, lower rates of first line CDKI utilization in patients receiving Medicare or in rural areas may be reflective of socioeconomic obstacles, which limit patient access to care. Further research is planned to investigate possible clinical or social determinants of these differences. Citation Format: Christopher DeHaven, Azadeh Nasrazadani, Adam Brufsky. Socioeconomic and geographic barriers affect rates of standard of care therapy utilization in patients with hormone receptor positive, HER2 negative metastatic breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-14-18.

We present four cases of intravascular large B-cell lymphoma (IVLBCL), a rare malignancy with poor outcomes. The exclusive presence of lymphoma cells in blood vessels leads to a heterogenous presentation and poor diagnostic yield with traditional initial diagnostic tools. Timely diagnosis and treatment can lead to improved outcomes.