CMS has released the 2027 Proposed Rules for both the Medicare Physician Fee Schedule (MPFS) and the Hospital Outpatient Prospective Payment System (OPPS), introducing several important changes that could impact radiation oncology providers across freestanding and hospital-based settings.
While CMS is proposing increases to several radiation treatment delivery services, the broader impact is more complex. Reductions to essential planning, management, physics, and other professional services, combined with a lower conversion factor, could create significant financial pressure for many radiation oncology practices.
Here’s what you need to know:
The 2027 MPFS Proposed Rule includes a mix of proposed increases and decreases for radiation oncology services. CMS is proposing to increase payment for certain radiation treatment delivery codes based on updated utilization data, while reducing Practice Expense (PE) Relative Value Units (RVUs) for many other essential services.
The overall impact will vary significantly by practice setting, treatment mix, image-guidance utilization, and the proportion of revenue derived from Medicare and Medicare Advantage plans. When the proposed changes are considered alongside the cumulative impact of prior payment changes since 2025, the outlook is particularly concerning for some radiation oncology providers.
Treatment Delivery Revaluation: CMS is proposing increases to the three primary radiation treatment delivery codes based on updated claims data and observed utilization patterns:
CMS determined that utilization of CPT 77412 was significantly lower than previously assumed, accounting for approximately 18% of treatment volume compared with the 35% utilization assumption used when establishing the 2026 rates. CMS is proposing to revalue CPT 77402, 77407, and 77412 to better reflect actual utilization.
Conversion Factor: CMS is proposing a reduction in the conversion factor for non-APM providers to $32.8409, down from $33.4009 in 2026. This reduction compounds the impact of proposed RVU changes across radiation oncology services.
Reductions to Essential Services: Many radiation oncology planning, treatment management, image guidance, physics, and related professional services are proposed for reductions. The final RBS analysis finds that other essential planning and management services have an average PE RVU reduction of approximately 4.9%.
SBRT and SRS: CMS is proposing reductions to professional reimbursement for SBRT and SRS services, despite proposing significant payment increases for these services under the OPPS. These treatments require substantial clinical, technical, planning, physics, and physician oversight resources, making the proposed reductions an important area of concern.
Practice-Level Impact: The financial impact will vary considerably based on treatment and image-guidance utilization. For example, practices relying heavily on cone-beam image guidance could see an overall revenue loss of approximately 2.5% to 3% compared with 2025, assuming 50% of revenue comes from Medicare or Medicare Advantage plans. Practices relying primarily on stereoscopic guidance could see a reduction of approximately 1% to 1.5%.
Freestanding practices may experience even greater variation. Based on typical utilization patterns, RBS estimates that practices may need approximately 40% Level 3 treatment utilization to reach revenue neutrality compared with 2025 reimbursement, higher than CMS’s original 35% utilization assumption.
Proton Therapy: CMS appears to be moving toward establishing a national payment rate for proton therapy delivery. Under the proposed methodology, the freestanding MPFS payment for proton therapy delivery would be approximately $1,029.56, while the proposed OPPS payment exceeds $1,434, creating a significant payment disparity between freestanding and hospital outpatient settings.
Proton therapy providers should closely monitor future rulemaking and consider the broader implications of CMS’s evolving methodology for valuing technical delivery services across sites of service.
Advocacy: The proposed changes make advocacy especially important for the radiation oncology community. Providers and stakeholders are encouraged to submit data-driven comments addressing the potential impact on patient access, staffing, technology investment, treatment availability, and the financial stability of cancer care programs.
The 2027 proposed OPPS rule includes several notable changes for hospital outpatient departments and other providers of radiation oncology services. In contrast to many of the proposed MPFS changes, the OPPS proposals include meaningful payment increases across a broad range of radiation oncology services.
Payment Rate Update: Hospitals that meet applicable quality reporting requirements would receive a proposed 2.4% increase in OPPS payment rates for CY 2027.
Radiation Oncology Payment Increases: CMS is proposing significant payment increases for many radiation oncology services, including treatment planning, treatment delivery, SRS/SBRT, proton therapy, brachytherapy, and other radiation services.
Treatment Delivery: Proposed payment increases for key radiation treatment delivery codes include:
SRS and SBRT: Proposed payment rates for stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) services are increasing, with several codes seeing approximately 14% increases.
Proton Therapy: Proposed OPPS payment rates for proton therapy services are increasing by approximately 12% to 14%, with proposed payment rates exceeding $1,434 for several proton delivery codes.
Site-Neutral Payment Expansion: CMS proposes expanding site-neutral payment policies to include certain imaging services furnished in excepted off-campus provider-based departments, while maintaining an exemption for rural sole community hospitals.
Biology-Guided Radiation Therapy (BgRT): CMS is proposing revised APC assignments and payment rates for BgRT services as additional claims data becomes available.
340B Drug Payment Changes: CMS proposes changing reimbursement for 340B-acquired drugs to Average Sales Price (ASP) minus 33.4%, replacing the current ASP +6% methodology. This proposed change could have important implications for outpatient oncology services and radiopharmaceuticals.
The 2027 Proposed Rules include significant changes that could affect radiation oncology reimbursement, with the impact varying considerably based on practice setting, treatment mix, and service utilization. The differences between the proposed MPFS and OPPS payment changes also highlight the importance of evaluating reimbursement at the individual practice and site-of-service level.
We encourage radiation oncology providers to carefully review these proposals and consider submitting comments to CMS. Data-driven feedback from the radiation oncology community can help CMS better understand the real-world impact of proposed payment policies on patient access, staffing, technology investment, treatment availability, and the financial stability of cancer care programs.
Comments are due by September 14, 2026.
Fill out the form on this page to download the full RBS 2027 MPFS and OPPS Proposed Rule Summary, including detailed analysis, year-to-year reimbursement comparisons, code-specific payment information, example cases, and additional insights into the potential financial impact across different practice settings.
Have questions about how these proposed changes could affect your organization? We’re here to help. Contact Radiation Business Solutions for more information or assistance navigating the 2027 proposed updates and understanding what they could mean for your practice.
