Skip to content
HCC Buddy home

C57.12 ICD-10-CM Code: Malignant neoplasm of left broad ligament

C57.12 maps to CMS-HCC V28 22 (RAF 0.363). Documentation must support MEAT. MEAT criteria · RAF calculator · free HCC coding tools

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

FY 2026 Apr update / Neoplasms (C00-D49) / Malignant neoplasms of female genital organs (C51-C58)

C57.12

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Malignant neoplasm of left broad ligament

Cancer that develops in the left broad ligament, the membrane that supports the uterus and reproductive organs on the left side.

Buddy the Bee presenting code insight

Buddy Insight

Left broad ligament cancer is a rare gynecologic malignancy requiring specific laterality documentation.

CMS-HCC V28

HCC 22

RAF 0.363

CMS-HCC V24

HCC 10

RAF 0.675

ACA/HHS

HCC 11

Varies by metal level

ESRD/PACE

HCC 10

RAF 0.111

RXHCC

HCC 22

RAF 0.124

Code Book Path

Official
C57Malignant neoplasm of other and unspecified female genital organs
C57.1Malignant neoplasm of broad ligament
C57.12Malignant neoplasm of left broad ligament

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for C57.12 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for C57.12 in this effective period.

Related Child Codes

Official
C57.10Malignant neoplasm of unspecified broad ligament
C57.11Malignant neoplasm of right broad ligament

Includes

Official

ICD-10-CM does not list Includes notes for C57.12 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for C57.12 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for C57.12 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for C57.12 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for C57.12 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance
Explicit documentation of left-sided location from imaging, operative note, or pathology
Histologic confirmation of malignancy
FIGO or TNM staging
Primary versus metastatic determination

MEAT Support

HCC Buddy guidance
Explicit documentation of left-sided location from imaging, operative note, or pathology
Histologic confirmation of malignancy
FIGO or TNM staging
Primary versus metastatic determination

Audit Caution

HCC Buddy guidance
Defaulting to the unspecified code C57.10 when laterality is available
Miscoding a secondary deposit in the broad ligament as a primary; metastatic disease codes differently
Using this code when the patient only has a personal history of this cancer (should use Z85.44)

Common Mistakes

HCC Buddy guidance
C57.10 — Unspecified broad ligament; always prefer C57.12 when left side is documented
C57.11 — Right broad ligament; verify laterality before coding
C56.2 — Left ovarian cancer; anatomically adjacent but distinct structure
C57.22 — Left round ligament; different ligament in the female pelvis

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is C57.12 an HCC code?

Yes. C57.12 (Malignant neoplasm of left broad ligament) maps to Bladder, Colorectal, and Other Cancers under the CMS-HCC V28 risk adjustment model (and Lymphoma and Other Cancers under V24), with a community non-dual aged RAF of 0.363. It is billable for payment year 2026.

Coder answer: C57.12 is billable and maps to V28 HCC 22, Bladder, Colorectal, and Other Cancers. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code
C57.12
Description
Malignant neoplasm of left broad ligament
HCC (V28)
HCC 22 — Bladder, Colorectal, and Other Cancers
RAF
0.363
Billable
Yes
Payment year
2026

HCC Category Mapping

V28HCC 22, Bladder, Colorectal, and Other Cancers
0.363
V24HCC 10, Lymphoma and Other Cancers
0.675
ESRDHCC 10, Lymphoma and Other Cancers
0.111
RxHCCHCC 22, Cancer, Other Specified Sites
0.124

Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

Work C57.12 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for C57.12

For C57.12 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

  • MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
  • EEvaluate: test results, medication response, or physical findings reviewed by the provider
  • AAssess: explicit mention in the assessment or plan with acknowledgment of status
  • TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed C57.12 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

C57.12 is the ICD-10-CM diagnosis code for malignant neoplasm of left broad ligament. Cancer that develops in the left broad ligament, the membrane that supports the uterus and reproductive organs on the left side. C57.12 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of female genital organs (c51-c58).

Under the CMS-HCC V28 risk adjustment model, C57.12 maps to Bladder, Colorectal, and Other Cancers (HCC 22) with a community, non-dual, aged base RAF weight of 0.363. Under the older CMS-HCC V24 model, C57.12 maps to Lymphoma and Other Cancers (HCC 10) with a community, non-dual, aged base RAF weight of 0.675. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

Confirm left side is explicitly documented in the medical record before assigning this code. Because C57.12 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for C57.12 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • •Confirm left side is explicitly documented in the medical record before assigning this code
  • •Distinguish from other uterine adnexa cancers; broad ligament is a specific anatomical location

Clinical Significance

Left broad ligament cancer is a rare gynecologic malignancy requiring specific laterality documentation. Accurate identification of the left side is critical for surgical planning and for distinguishing primary disease from contralateral metastasis. This code represents the highest specificity available for this anatomic site.

Documentation Requirements

  • ✓Explicit documentation of left-sided location from imaging, operative note, or pathology
  • ✓Histologic confirmation of malignancy
  • ✓FIGO or TNM staging
  • ✓Primary versus metastatic determination
  • ✓Active treatment status or surveillance documentation

Commonly Confused Codes

  • •C57.10: Unspecified broad ligament; always prefer C57.12 when left side is documented
  • •C57.11: Right broad ligament; verify laterality before coding
  • •C56.2: Left ovarian cancer; anatomically adjacent but distinct structure
  • •C57.22: Left round ligament; different ligament in the female pelvis

Child Codes

C57.10Malignant neoplasm of unspecified broad ligament
HCC 22
C57.11Malignant neoplasm of right broad ligament
HCC 22
C57.12Malignant neoplasm of left broad ligament
HCC 22

Code Hierarchy

└C57Malignant neoplasm of other and unspecified female genital organs└C57.1Malignant neoplasm of broad ligament└C57.12Malignant neoplasm of left broad ligament
└C57.12Malignant neoplasm of left broad ligament

Because C57.12 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

C57.12 maps to CMS-HCC V28 category 22, Bladder, Colorectal, and Other Cancers. See the ICD-10 to HCC mapping hub for how the V28 crosswalk works. Because C57.12 carries a payment HCC, you can see what it adds to a RAF score and check the documentation the chart needs before it is submitted.

Work C57.12 in HCC Buddy

Open C57.12 in the Code Book for the full Index-to-Tabular path, MEAT checklist, and V28 HCC mapping, or in the Encoder to code from a keyword search. Pro includes 7 days to try everything, no card required.

Open in Code BookOpen in EncoderStart Pro