Radical resection of a malignant soft tissue tumor of the neck or anterior thorax, with the tumor and excised margins measuring less than 5 cm in total.

Verified May 8, 2026 · 5 sources ↓

Medicare: $882.45
Work RVU: 14.38
Global, days: 90
Region: Other

Drawn from CMSEmedny

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 5 cited references ↓

Operative note must state the anatomic location as neck or anterior thorax — not just 'chest' or 'neck mass'
Pathology report or intraoperative assessment supporting malignant or suspected malignant neoplasm (e.g., sarcoma)
Specimen dimensions documenting excised tumor plus margins measuring less than 5 cm
Description of radical resection technique, including extent of tissue removed (fascia, muscle, adjacent structures)
Pre-operative imaging or biopsy confirming soft tissue origin and ruling out rib or chest wall bony involvement
Surgeon attestation that resection was performed with oncologic margins, not simple or wide local excision

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 52 Reduced services 59 Distinct service 62 Co-surgeons 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global 24 Unrelated E/M during global 25 Significant separate E/M LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 21557 covers radical resection of a soft tissue tumor — typically a sarcoma or other malignant neoplasm — located in the neck or anterior thorax, where the combined tumor-plus-margin specimen measures less than 5 cm. 'Radical resection' distinguishes this from simple or wide excision: the surgeon removes the tumor with an intentionally wide margin of surrounding normal tissue, often including adjacent fascia or muscle, to achieve oncologic clearance. The less-than-5-cm threshold is measured against the resected specimen, not the imaging estimate, so operative documentation must reflect the actual excised dimensions.

This code carries a 90-day global period. All routine post-op visits, wound checks, and dressing changes through day 90 are bundled — bill separately only for unrelated services (modifier 24) or a significant separately identifiable E&M on the day of a related minor procedure (modifier 25). If tumor size equals or exceeds 5 cm, step up to 21558. For tumors of the neck or thorax not involving the ribs, do not use 21601 — that family of codes applies to chest wall tumors with rib involvement. If the procedure is performed at a non-contiguous anatomic site alongside another separately reportable resection, modifier 59 or XS may be appropriate per NCCI guidance.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU vs. total RVU

The work RVU (14.38) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (26.42) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	14.38
Practice expense RVU	8.92
Malpractice RVU	3.12
Total RVU	26.42
Medicare national rate	$882.45
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$882.45
HOPD (APC 5073) Hospital outpatient department	$2,967.63
ASC (PI G2) Ambulatory surgical center (freestanding)	$1,248.36

Common denial reasons

The recurring reasons claims for CPT 21557 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Upcoding or downcoding challenge when specimen size crosses the 5 cm threshold — operative note and path report must agree
Bundling denial when 21557 is billed same-day with a lesser excision code (21555 or 21556) at the same anatomic site without a valid modifier
Medical necessity denial when pathology or pre-op documentation doesn't support malignant or aggressively resected neoplasm
Global period violation — post-op E&M billed within 90 days without modifier 24 for an unrelated condition
Site specificity rejection when operative note references chest wall with rib involvement, triggering auditor redirect to 21601 family

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01What separates 21557 from 21556?

21556 is subfascial excision of a benign or non-radical tumor less than 5 cm. 21557 is reserved for radical resection — wide margins, oncologic intent, typically malignant neoplasm. The operative technique and pathologic context determine the correct code, not size alone.

02How is the less-than-5-cm threshold measured?

CMS and coding guidance apply the size threshold to the excised specimen including margins, not the pre-operative imaging measurement of the tumor mass itself. Document specimen dimensions in the operative note and confirm against the pathology report.

03Can 21557 and 21558 both be billed if tumors are at separate sites in the same operative session?

Only if the resections are at genuinely distinct anatomic sites — for example, one lesion in the neck and a separate lesion in the anterior thorax with no contiguous overlap. Use modifier 59 or XS and provide clear documentation of separate locations. Contiguous structures in the same region are not separate sites under NCCI rules.

04Is modifier 62 (co-surgeon) supported for 21557?

Yes, when two surgeons of different specialties — commonly surgical oncology and thoracic or head-and-neck surgery — each perform distinct portions of the resection. Both surgeons bill 21557 with modifier 62, and each operative note must describe their individual contribution.

05What triggers a step-up to 21558?

When the radical resection specimen (tumor plus excised margins) measures 5 cm or greater, bill 21558 instead. Do not use 21557 and add modifier 22 as a workaround for a large specimen — that's a coding error, not a complexity flag.

06How does the 90-day global period affect post-op oncology management visits?

Routine surgical follow-up is bundled through day 90. If the oncologist or a different provider is managing chemotherapy, radiation planning, or an unrelated condition during that window, those E&M visits are separately billable — use modifier 24 for unrelated post-op E&M or modifier 79 for an unrelated procedure performed during the global period.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira Scribe

Mira's AI scribe captures the tumor location (neck vs. anterior thorax), the radical resection technique including margin description, and the final specimen dimensions from the operative dictation — then flags if the documented size approaches or exceeds 5 cm, prompting review of whether 21558 applies instead. This prevents the most common audit trigger: a mismatch between the code's size threshold and the pathology report.

See how Mira captures CPT 21557 documentation