HCPCS code C1720: Deleted, bill C2640 or C2641 instead

Key takeaways

HCPCS code C1720 described a brachytherapy source, palladium-103, per source. It is a deleted Level II C-code.

CMS deleted C1720 effective July 1, 2007 in the quarterly OPPS update issued as Transmittal CR5623.

Two active codes replaced it. C2640 covers stranded palladium-103 sources, and C2641 covers non-stranded sources.

C1720 was never an iodine-125 code. Iodine-125 sat under C1718, now billed as C2638 or C2639.

Both replacement codes are billed per seed, so claim units must match the source count in the implant record.

HCPCS code C1720 described a brachytherapy source, palladium-103, per source. CMS deleted it on July 1, 2007, so it pays nothing today.

The seeds themselves are still payable. CMS split that one isotope-only code into two configuration-specific codes, C2640 and C2641. Which one belongs on the claim comes down to a single line in the implant record.

That line records whether the seeds arrived preloaded in a strand. Miss it, and your coder is guessing. Leave C1720 sitting in the chargemaster, and the line rejects on every case.

HCPCS code C1720 paid for one palladium-103 seed

One unit of C1720 meant one palladium-103 seed. The code lived in the HCPCS Level II C-series, which covers devices and supplies paid under the Outpatient Prospective Payment System (OPPS).

The Centers for Medicare and Medicaid Services (CMS) assigns C-codes. CPT codes come from the American Medical Association, so the two sets are maintained separately.

The long descriptor read: Brachytherapy source, palladium-103, per source. It named the isotope and the billing unit. It said nothing about how the seeds were packaged, and that omission is what CMS eventually fixed.

You can confirm the deletion before you touch a claim. The AAPC deleted-code entry lists the termination date and the active replacement. The CMS HCPCS Level II files carry the same record.

Is HCPCS code C1720 still active?

No. C1720 was terminated on June 30, 2007, and it has carried deleted status since July 1, 2007. Send it on a claim now and the line rejects, because payer systems no longer recognize the code.

CMS made the change in Transmittal CR5623, the July 2007 quarterly OPPS update. The 2008 annual HCPCS file reflects it too. Deletions timed like this one slip past teams that review codes only each January.

Four things follow from a deletion like this one:

• A deleted code cannot be billed: payers drop it from their fee schedules, so claims carrying it fail at front-end edits.
• The service is still payable: palladium-103 seed implants remain billable under the replacement codes. CMS retired the code, not the procedure.
• Historical claims stay correct: for dates of service before July 1, 2007, C1720 was the right code. Only current billing changes.
• Chargemaster entries linger: one outdated line repeats the same denial on every claim for that service, often for months.

Recovery Audit Contractor and Medicare Administrative Contractor reviews both reach back into old claims. So check your code library against every HCPCS update, not just the annual one. C1720 is the argument for reading the quarterly transmittals too.

What code replaced HCPCS code C1720?

Two codes replaced it. C2640 is brachytherapy source, stranded, palladium-103, per source. C2641 is brachytherapy source, non-stranded, palladium-103, per source. Both are active, and both are billed one unit per seed.

CMS restructured the whole source family in that same July 2007 update. It deleted three isotope-only codes and added eight that separate stranded sources from non-stranded ones. The isotope stayed put, and the packaging became part of the code.

So the choice between C2640 and C2641 is a documentation question. Seeds supplied preloaded in an absorbable strand are reported with C2640. Loose seeds placed one at a time are reported with C2641.

Retiring C1720 from a billing setup takes five steps:

1. Look up C2640 and C2641 in the current CMS HCPCS Level II file and confirm both are active.
2. Check the current OPPS Addendum B for each code’s status indicator and payment rate.
3. Remove C1720 from the chargemaster, along with C1718 and C2633 if either is still listed.
4. Confirm the replacement codes are loaded in the payer fee schedules your billing system draws from.
5. Re-map any saved claim templates or order sets that still point at the deleted code.

Two clinical details decide the palladium-103 code you bill

Those two details are the isotope and the configuration. The code paid for the radioactive source itself, never for the work of implanting it. That puts the burden on the clinical record to describe the source precisely.

How palladium-103 seeds deliver their dose

Brachytherapy places a radiation source inside or next to a tumor. In low-dose-rate (LDR) prostate brachytherapy, a physician implants small sealed seeds into the gland under ultrasound guidance. The seeds stay in permanently and decay over the following weeks.

Palladium-103 has a half-life of about 17 days and an average photon energy near 21 keV. Iodine-125 decays far more slowly, over roughly 60 days. Palladium-103 therefore delivers its dose in a much shorter window.

Each isotope has its own source codes, so swapping the isotope changes the code. Iodine-125 sits under C2638 and C2639, cesium-131 under C2642 and C2643, and palladium-103 under C2640 and C2641.

Treatment site matters as much as isotope. Palladium-103 and iodine-125 dominate permanent prostate seed implants. That keeps this part of the code family close to urology and men’s health practices. High dose rate iridium-192 is the workhorse for gynecologic brachytherapy, so OBGYN practices meet a different part of it.

Stranded or loose seeds change the code

Configuration decides which of the two palladium-103 codes belongs on the claim:

Configuration is also where brachytherapy coding goes wrong most often. The implant report has to state the isotope, the configuration, and the number of sources used. Structured digital forms capture those three fields at the point of care.

How a palladium-103 source claim moves today

The claim moves in two halves. The facility reports the seeds with the HCPCS source code, and the physician reports the implant with a CPT code. They are separate claims drawn from the same operative note.

From the operative note to a clean claim

The facility side runs like this.

1. Read the configuration off the operative note and pick C2640 for stranded seeds or C2641 for loose ones.
2. Confirm C1720 is gone from the chargemaster. One stale line keeps generating the same rejection.
3. Count the sources. These codes bill per source, so claim units equal the number of seeds implanted.
4. Report the source code on the UB-04 under revenue code 0333 for radiation therapy, or the revenue code your payer specifies.
5. Add the CPT code for the implant. CPT 55875 covers transperineal placement of needles or catheters into the prostate, and 77778 covers the complex interstitial application.
6. Link the claim to a supporting diagnosis, usually C61 for prostate cancer, and keep any payer authorization on file.

Quantity is where these claims live or die. If the physics report documents 85 seeds and the claim bills 85 units, the two agree and the line clears. If they differ, expect a medical review request or a recoupment on audit.

Before you submit

Run these five checks before the claim leaves the building:

• The isotope in the note matches the isotope in the code you chose.
• The configuration in the note matches the code, stranded against non-stranded.
• The unit count on the claim equals the implanted source count in the physics report.
• The source code was active for the date of service, not just active today.
• The diagnosis and any prior authorization sit in the record, with authorized quantity matching billed quantity.

Three mistakes that stall these claims

• Coding by isotope alone. On a two-code family that is a coin flip. Almost every retired source code now has two successors, and only the configuration separates them.
• Letting the unit count drift. Unit-based HCPCS codes all behave this way. A drug code such as J0561 ties units to a documented quantity, and the same mismatch triggers the same review.
• Rebuilding the count later. A seed count reconstructed weeks after the implant will not hold up. The same rule governs 17312, where each additional Mohs stage has to be recorded as it happens.

Medicare still pays separately for brachytherapy sources

The deletion of C1720 was a descriptor change. Payment for palladium-103 seeds carried on under the successor codes, still reported one unit per source.

Medicare paid hospitals for brachytherapy sources at charges reduced to cost through the end of 2009. From calendar year 2010, CMS began setting prospective OPPS rates for each source code. Those rates are published annually in OPPS Addendum B.

In Addendum B, active source codes carry status indicator U. That flags them as brachytherapy sources paid separately from the procedure APC. A deleted code has no status indicator and no rate, which is why the line pays nothing.

Rates move with each OPPS final rule, so a prior-year figure should never drive a current billing decision. Check the current Addendum B for facility rates, and the CMS fee schedule lookup for the professional component.

Which brachytherapy C-codes survived the 2007 restructure

Four of the six codes in this block are still active. C1720 sat inside a small family covering brachytherapy needles and sources. Knowing which members survived saves guesswork when an old code turns up in a chargemaster.

Notice the pattern in the survivors. C1716, C1717, and C1719 all specify non-stranded sources. CMS never created stranded counterparts for gold-198 or iridium-192, because only the seed isotopes used in permanent implants picked up a matched pair.

The C-series reaches well beyond radiation oncology. Device codes such as C1785 sit in the same series and follow the same OPPS logic. So the quarterly update that retired C1720 is worth reading whatever your specialty.

Documentation is what defends a per-source claim

Per-source billing ties the claim amount straight to a seed count, which is why these claims attract review. A difference between the documented quantity and the billed quantity is the most common audit trigger in radiation oncology.

What the record has to show

• Operative note or implant summary: the isotope, the configuration, the total source count, and the implant site.
• Physics report: source strength, seed activity, and treatment plan parameters, which support both medical necessity and the count.
• Pathology and diagnosis records: the indication, such as localized prostate cancer, tying the service to a billable diagnosis.
• Prior authorization: for commercial payers, keep the approval on file and match the authorized quantity to the billed quantity.

Why a mid-year deletion is easy to miss

C1720 went away on July 1, not January 1. A practice reviewing codes once a year would have billed a deleted code for six months before noticing. Two problems follow.

First, every affected claim needs reworking, which puts timely filing deadlines at risk. Second, the pattern can hide inside a general denial backlog for months. Tie your revenue cycle management reviews to each CMS update cycle, quarterly as well as annual, and that window closes.

How Pabau keeps source detail attached to the claim

The coding decision on this page depends on detail captured in the treatment room. The isotope, the configuration, and the seed count all live in clinical documentation. When that documentation sits in a scanned PDF nobody can find, the coder ends up guessing.

Pabau is practice management software that keeps clinical records and billing in one system. Treatment notes and digital forms capture the fields your coder needs, stored against the patient record. The source count on a claim traces back to the note that documents it.

On the billing side, Pabau’s claims management checks each claim for the submission fields the insurer requires. Nothing goes out incomplete. A status dashboard then shows where every submitted claim stands.

So your team spends less time reopening claims to work out what was missing. It also spends less time rebuilding an implant record months later because a payer asked for it.

Keep implant detail attached to the claim

Pabau holds treatment notes, digital forms, and claim status in one system. The isotope, configuration, and source count behind a claim stay one click away.

Book a demo

Conclusion

The work left on C1720 is small and specific. Pull it out of the chargemaster, load C2640 and C2641, and the palladium-103 line pays again.

What lasts longer is the documentation habit. If every implant note states the isotope, the configuration, and the source count, your coder never has to guess. The choice between two live codes stops being a judgment call. That habit still holds when the next quarterly update moves something else.

Pabau keeps that clinical detail attached to the record your coder bills from, and tracks each claim through to payment. Book a demo to see how it handles radiation oncology documentation and claim status.

Continue your research

Tracking another code CMS retired? CPT code 55700 walks through a 2026 deletion and the codes that replaced it.

Need the screening code that comes first? HCPCS code G0103 covers the prostate-specific antigen test that often starts this pathway.

Coding brachytherapy in the UK? CCSD code X6015 explains how high dose brachytherapy preparation is reported.

Billing the anesthesia for a perineal approach? CPT code 00908 covers anesthesia for perineal prostatectomy.

Reviewing radiology codes in the same update cycle? HCPCS code G0279 sets out the billing rules for digital breast tomosynthesis.

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