Z17.421 – Hormone receptor negative with human epidermal growth factor receptor 2 negative status

ICD-10-CM 2027 diagnosis code · Estrogen, and other hormones and factors receptor status (Z17)

Billable code

ICD-10-CM code Z17.421

Code: Z17.421 (claims format: Z17421)
Description: Hormone receptor negative with human epidermal growth factor receptor 2 negative status
Short description: Hormone recept neg w hmn epdrml grth fctr recept 2 neg stat
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 21. Factors influencing health status and contact with health services (Z00-Z99)
Block: Z17 Estrogen, and other hormones and factors receptor status (Z17)
Parent codes: Z17 › Z17.4 › Z17.42

Notes for Z17.421

Applicable to:

HR- with HER2-
TNBC
Triple negative breast cancer

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

Z17 – Estrogen, and other hormones and factors receptor status

Code first:

malignant neoplasm, such as:
malignant neoplasm of breast (C50.-)
malignant neoplasm of ovary (C56.-)

Notes:

Use one code, as available, for each receptor: Z17.0, Z17.1, Z17.2-, Z17.3-

Z17.4 – Combined receptor status

Notes:

Assign a code from subcategory Z17.4- when only a combined receptor status is documented

Z17.42 – Hormone receptor negative

Applicable to:

Index terms for Z17.421

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in Z17.42

Z17.420 – Hormone receptor negative with human epidermal growth factor receptor 2 positive statusBillable

Frequently asked questions

What is ICD-10 code Z17.421?

Z17.421 is the ICD-10-CM code for hormone receptor negative with human epidermal growth factor receptor 2 negative status, in the block Z17 (Estrogen, and other hormones and factors receptor status (Z17)).

Is Z17.421 a billable code?

Yes. Z17.421 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does Z17.421 belong to?

It belongs to category Z17 – Estrogen, and other hormones and factors receptor status.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.