2026 ICD-10-CM Diagnosis Code C79.10Secondary malignant neoplasm of unspecified urinary organs

ICD-10-CM Codes›C00–D49›C76-C80›C79

ICD-10-CM C79.10
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C79.10 is a billable ICD-10-CM diagnosis code for secondary malignant neoplasm of unspecified urinary organs. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 656 through 658, 686 through 688. Coders also document this condition as metastatic malignant neoplasm to urinary system. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Secondary malignancies.

Code Identity

ICD-10-CM Code
C79.10
Billable Status
Yes — Valid for Submission
Code Describes
Secondary malignant neoplasm of unspecified urinary organs
Short Description
Secondary malignant neoplasm of unspecified urinary organs
Same as the full description in the CMS dataset.
Parent Code
C79.1
Secondary malignant neoplasm of bladder and other and unspecified urinary organs

Code Classification

ChapterC00–D49Neoplasms
SectionC76-C80Malignant neoplasms of ill-defined, other secondary and unspecified sites
CategoryC79Secondary malignant neoplasm of other and unspecified sites
This CodeC79.10Secondary malignant neoplasm of unspecified urinary organs

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Metastatic malignant neoplasm to urinary system
  • Metastatic transitional cell carcinoma to upper urinary tract

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO070
Secondary malignancies
Default principal diagnosis: inpatient Yes · outpatient Yes

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary		Malig.
Secondary		Ca
in situ		BenignUncertainUnspec.
urinary organ or systemC68.9C79.10D09.10D30.9D41.9D49.59

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Convert C79.10 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
198.1 Sec malig neo urin NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C79.10Overview

Is C79.10 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report secondary malignant neoplasm of unspecified urinary organs on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C79.10 group to?

When secondary malignant neoplasm of unspecified urinary organs is the principal diagnosis on an inpatient stay, it groups to MS-DRG 656, 657, 658, 686, 687, 688, with relative weights from 0.7903 to 3.1838 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C79.10?

Under the General Equivalence Mappings, secondary malignant neoplasm of unspecified urinary organs converts to ICD-9-CM 198.1 (sec malig neo urin NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.