2026 ICD-10-CM Diagnosis Code C44.590Other specified malignant neoplasm of anal skin
ICD-10-CM Codes›C00–D49›C43-C44›C44
- Billable — Valid for Submission
- Chronic Condition
C44.590 is a billable ICD-10-CM diagnosis code for other specified malignant neoplasm of anal skin. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. Coders also document this condition as perianal Paget's disease. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Skin cancers - all other types.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Perianal Paget's disease
- Primary extramammary Paget disease of skin
- Primary malignant neoplasm of perianal skin
- Primary perianal Paget disease
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Other specified malignant neoplasm of anal margin
- Other specified malignant neoplasm of perianal skin
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.
- extramammary - See Also: Neoplasm, skin, malignant;
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Paget's disease
- extramammary
- anus
- margin
- Paget's disease
- extramammary
- anus
- skin
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. |
|---|---|---|---|---|---|---|
| anus, anal › skin › specified type NEC | C44.590 | – | – | – | – | – |
| skin NOS › anus › specified type NEC | C44.590 | – | – | – | – | – |
Patient EducationClinical
Skin Cancer
Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert C44.590 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C44.590Overview
Is C44.590 (Other specified malignant neoplasm of skin of trunk) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report other specified malignant neoplasm of anal skin on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does C44.590 group to?
When other specified malignant neoplasm of anal skin is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of C44.590?
Under the General Equivalence Mappings, other specified malignant neoplasm of anal skin converts to ICD-9-CM 173.59 (malig neo skin trunk 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.
