How we updated the Iridium Suite claim scrubber for the 2026 radiation oncology codes
On January 1, 2026 the radiation oncology code set changed more than it had in a decade. CPT deleted the IMRT delivery codes, the CT guidance code and port films, CMS retired the G-codes that freestanding centers had used since 2015, and treatment delivery became three levels: 77402, 77407 and 77412. Each of those changes affects at least one rule in a billing system. This is how we approached the update in the Iridium Suite claim scrubber, and what we suggest every practice check, whatever system it bills on.
We are writing it down because billers should know what their software checks for them, and because the reasoning is useful even if you bill elsewhere.
What changed in the code set
| Before 2026 | From January 1, 2026 |
|---|---|
| Treatment delivery by energy and complexity: 77401 to 77416, plus G6003 to G6016 for freestanding centers | Three levels: 77402 (Level 1), 77407 (Level 2, single isocenter 3D or IMRT), 77412 (Level 3: multiple isocenters, or active motion management, or total skin electrons, or mixed electron and photon fields) |
| IMRT delivery 77385 and 77386 | Deleted; the work is inside 77407 and 77412 |
| Image guidance 77014, G6001, G6002, G6017, and 77387 with a technical component | 77387 with modifier 26 only; the technical side is bundled into delivery in every setting |
| Port films 77417 | No separate payment (status B) |
| Superficial and orthovoltage under the old delivery codes | New codes 77436 to 77439 |
The 2026 delivery codes article explains the tiers. The CMS summary is in the CY 2026 Physician Fee Schedule final rule fact sheet.
How we approached it
A claim scrubber is a set of rules that look at a charge before it becomes a claim. When a code set changes this much, the rules fall into three groups, and each group needs a different kind of attention.
Rules written around codes that no longer exist. A rule that pairs devices with the old IMRT delivery code, or adds modifier 26 to the deleted CT guidance code, would produce wrong warnings all year. Rules like these were retired rather than deleted, so a practice cleaning up charges from late 2025 can still see what a rule used to check.
Rules that still apply but named the old codes. The weekly management count behind 77427, the modifier rules for devices billed with delivery, the frequency rules for planning and simulation: all still valid, each updated to the 2026 code list. The fraction counting itself did not change, because the 2026 codes did not change what counts as a fraction.
New rules for the new codes. The 2026 code set has new requirements that are easy to get wrong. These are the checks that were added:
- A deleted-code warning. A charge carrying a code that existed in 2025 but not for a 2026 date of service is stopped with a message that names the codes that replaced it. It is a warning, not an automatic replacement, because there is no one-to-one map from the old delivery codes to the new levels; only the treatment plan shows whether a course is Level 2 or Level 3, and a software guess would cause more errors than a stopped charge.
- Image guidance as professional only. 77387 is billed with modifier 26 in every setting in 2026, including a freestanding center that bills everything else globally. A system that assigns modifiers by site of service, ours included, would get this wrong without a specific rule, so there is one.
- The diagnosis on treatment planning. ICD-10-CM expects Z51.0, “encounter for antineoplastic radiation therapy”, as the primary diagnosis on an antineoplastic course, with the cancer diagnosis secondary. Many practices never did this and were paid anyway, so it was easy to forget. The scrubber now asks about it when a planning code is billed without Z51.0. It asks rather than changes, because not every course of radiation is antineoplastic.
- Telehealth on the weekly visit codes. CMS made 77427 a permanent telehealth-list code (video required) and left 77431, 77432 and 77435 off the list. A visit code billed for a telehealth setting the list does not allow is flagged before the claim goes out.
Charge codes from the treatment system
Most radiation oncology charges come from the record-and-verify system, and many practices have crosswalks that translate those charge codes into billing codes. A crosswalk that mapped to G-codes is now wrong. Those tables belong to the practice, and in a hospital-based arrangement to the hospital. The scrubber catches a deleted code at import, and we work through the table updates with each practice. The Record and Verify charge capture article walks through that review step by step.
What to check in your own practice
- Charges from the treatment system. Open a week of imported charges and look for any of the deleted codes. If they are still arriving, the fix is in Aria, Mosaiq or whichever system captures the charge, not in billing.
- 77387 on your claims. Every line should carry modifier 26, even for freestanding centers. Check a paid remittance from February or later to see that the professional payment arrived.
- The delivery level. Pull the last twenty courses and confirm the level matches the plan: single isocenter without motion management is 77407, not 77412, however complex the IMRT.
- Z51.0. Decide as a practice whether to carry it as the primary diagnosis on antineoplastic courses, then make it a habit at the planning step.
- Weekly visits by video. 77427 can be done by video; 77431, 77432 and 77435 cannot.
The claim scrubber page describes how the rules are configured per practice and per payer; the practical point of all of the above is that a rule is only useful if it matches the code set the payer is using today.
Further reading: CY 2026 Physician Fee Schedule final rule fact sheet; What the 2026 Medicare fee schedule means for radiation oncology billing; CPT 77427.