2026 ICD-10-CM Diagnosis Code C80.0Disseminated malignant neoplasm, unspecified
ICD-10-CM Codes›C00–D49›C76-C80›C80
- Billable — Valid for Submission
- Chronic Condition
C80.0 is a billable ICD-10-CM diagnosis code for disseminated malignant neoplasm, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 826 through 830, 843 through 845. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Malignant neoplasm, unspecified.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Adenocarcinoma carcinomatosis
- Carcinomatosis
- Chorea due to widespread metastatic malignant neoplastic disease
- Melanoma carcinomatosis
- Metastatic small cell neuroendocrine carcinoma
- Multiple malignancy
- Small cell carcinoma carcinomatosis
- Squamous cell carcinomatosis
- Undifferentiated large cell carcinomatosis
- Widespread metastatic malignant neoplastic disease
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Carcinomatosis NOS
- Generalized cancer, unspecified site (primary) (secondary)
- Generalized malignancy, unspecified site (primary) (secondary)
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Carcinoma (malignant) - See Also: Neoplasm, by site, malignant;
- Carcinomatosis - C80.0
- unspecified site (primary) (secondary) - C80.0
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Carcinoma(malignant)
- generalized, with unspecified primary site
- Carcinomatosis
- Carcinomatosis
- unspecified site (primary) (secondary)
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Table of NeoplasmsClinical
Anatomical sites in the Table of Neoplasms that reference this code family.
| Site | Malig. Primary | Malig. Secondary | Ca in situ | Benign | Uncertain | Unspec. |
|---|---|---|---|---|---|---|
| disease, generalized | C80.0 | – | – | – | – | – |
| disseminated | C80.0 | – | – | – | – | – |
| generalized | C80.0 | – | – | – | – | – |
Patient EducationClinical
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Read the full article at MedlinePlus
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Convert C80.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C80.0Overview
Is C80.0 (Malignant neoplasm without specification of site) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report disseminated malignant neoplasm, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does C80.0 group to?
When disseminated malignant neoplasm, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 826, 827, 828, 829, 830, 843, 844, 845, with relative weights from 0.8516 to 4.6778 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of C80.0?
Under the General Equivalence Mappings, disseminated malignant neoplasm, unspecified converts to ICD-9-CM 199.0 (malig neo disseminated). The mapping is a direct match.
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.
