PS5-11-04: Patient Out-of-Pocket Exposure from Initial Staging Breast MRI: Quantifying Financial Toxicity in Breast Cancer Care

Abstract Background: Breast MRI is routinely considered at initial diagnosis to evaluate extent of disease, multicentricity, and contralateral disease in the non-metastatic setting, despite randomized data (e.g., COMICE & MONET) showing little impact on re-excision rates or long-term outcomes. In addition to time delays, each scan may expose patients to out-of-pocket expenses that compound “financial toxicity,” a quality-of-life domain now tracked by ASCO and NCCN. We audited all first-episode breast MRIs at a large community system during 2024 to clarify the economic burden. Methods: Retrospective billing data of all breast cancer MRI scans (ICD-10 C50.x code present in at least 1 of the first 5 diagnosis fields) performed in calendar-year 2024 at a community hospital system was analyzed in this IRB approved study. Cases were included if they had both Hospital (HB) and Professional Billing (PB) available. Only the “initial episode” MRI for each patient, defined as the earliest service date, was used. Primary endpoint was the posted “Patient Payment Amount”. Descriptive statistics including Spearman, Kruskal-Wallis and chi2 were performed using Python 3.11 (pandas, scipy) Results: A total of 630 patients underwent a breast MRI in 2024. There was no difference in MRI distribution by service month. CPT code 77049 was billed in 95.4% of scans. Payer grouping included 53.0% Commercial, 32.7% Medicare, 11.7% ACA Marketplace, and 2.7% Military / Self-Paid / Other. Of all “Net Charges”, patients were liable for 13.4 %, insurers covered 75.4 %, and the hospital system had a gap of 11.2 %. For PB, 98.3 % of patients had a $0 copay, and among the 1.7% who did owe, median out-of-pocket responsibility was $94 (IQR $34-$100). The upper 10% of payers owed >$135, and the highest bill was $177 (skew = 0.46). For HB, 63.2% had $0 copay, and among the 36.8% who did owe, median out-of-pocket responsibility was $327 (IQR $171-$648). Ten percent of payers owed >$1,300, and the highest bill was $4,878 (skew = 2.8). For the combined PB + HB exposure, 64.0% of patients had a net $0 copay (including 1.3 % with small credits). Among the 36.0 % who owed anything, median out-of-pocket responsibility was $326 (IQR $174-$645). The upper 10 % of payers owed >$1,290, and the highest total bill was $4,878 (skew = 2.8). Patient responsibility did not show a consistent deductible effect: the proportion of $0 visits rose from 46% in January to 70% in December (Spearman p = 0.07), yet mean liability among paying patients fluctuated throughout the year (p = 0.32). Patient cost sharing with $0 co-pay by Payer class varied from 33.8% for ACA Marketplace, 49.7% for Commercial, 50% Military, 93.2% Medicare, and 100% for Medicaid, Self-Paid, and Other. Among patients who incurred >$0 liability, median responsibility was highest in Commercial plans ($453.09), followed by ACA Marketplace ($184.67), Medicare ($70.81), and Military ($30.50). Conclusions: Patient-level "financial toxicity" from an initial staging breast MRI is relatively minimal in our system—63 % of patients paid nothing and the remainder faced a median $327, almost entirely from the technical fee. These findings reassure clinicians that ordering a breast MRI seldom imposes a direct out-of-pocket burden on patients, though up-front cost counselling is important to prevent the rare but substantial financial surprises we identified. Cost-sharing burden fell mainly on ACA Marketplace and Commercially insured patients; Medicare and Medicaid beneficiaries were largely shielded. In a value-based oncology landscape, the decision to order a staging breast MRI should weigh its uncertain clinical benefit against not merely the patient’s copay at the point of care, but also system-level costs of both the hospitals that absorb charity-care write-offs and occasional under-collections, and the payers that cover the bulk of charges. Citation Format: C. Dvorak, H. Saunders, T. Dvorak, J. Smith. Patient Out-of-Pocket Exposure from Initial Staging Breast MRI: Quantifying Financial Toxicity in Breast Cancer Care [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS5-11-04.