Question 1

What is ICD-10 code N80.A59?

Accepted Answer

N80.A59 is the ICD-10-CM diagnosis code for deep endometriosis of unspecified ureter. Endometrial tissue grows deeply into a ureter, but the specific side (right, left, or bilateral) is not documented or specified. N80.A59 sits in the ICD-10-CM chapter for diseases of the genitourinary system (n00-n99), within the section covering noninflammatory disorders of female genital tract (n80-n98).

N80.A59 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Use this code only when deep ureteral endometriosis is confirmed but laterality is not specified in the documentation.

Question 2

Is N80.A59 an HCC code?

Accepted Answer

No. N80.A59 is a billable ICD-10-CM code but does not map to any payment HCC category under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can still be reported on Medicare Advantage encounter data submissions, but it does not contribute to the beneficiary's Risk Adjustment Factor (RAF) score and therefore does not affect the risk-adjusted capitation payment to the plan. V28 reached 100% phase-in for payment year 2026.

Question 3

Is N80.A59 billable?

Accepted Answer

Yes. N80.A59 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. N80.A59 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

Which HCC does N80.A59 map to under V28?

Accepted Answer

N80.A59 does not map to a CMS-HCC V28 payment category. Check the current CMS-HCC V28 model file for payment year 2026 rather than an older V24 tip sheet.

Question 5

What does N80.A59 pay in RAF?

Accepted Answer

N80.A59 has no separately stated V28 community RAF weight. If it is not a V28 payment HCC, it adds nothing to a community RAF score.

Question 6

What is the V28 vs V24 difference for N80.A59?

Accepted Answer

N80.A59 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither community model rewards N80.A59 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's V28/V24 community RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a community payment HCC.

Question 7

What documentation supports N80.A59?

Accepted Answer

Use this code only when deep ureteral endometriosis is confirmed but laterality is not specified in the documentation Attempt to clarify laterality with the provider, as this information affects treatment planning and prognosis N80.A59 is not a CMS-HCC payment code, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

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N80.A59

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N80.A59 ICD-10-CM Code: Deep endometriosis of unspecified ureter

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N80.A59

Is N80.A59 an HCC code?

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What This Code Means

Coding Tips

Child Codes

Code Hierarchy

N80.A59 code history

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