2026 ICD-10-CM Diagnosis Code C44.520Squamous cell carcinoma of anal skin
ICD-10-CM Codes›C00–D49›C43-C44›C44
- Billable — Valid for Submission
- Not Chronic
C44.520 is a billable ICD-10-CM diagnosis code for squamous cell carcinoma 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Skin cancers - squamous cell carcinoma.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Carcinoma of skin of anus
- Primary malignant neoplasm of perianal skin
- Primary squamous cell carcinoma of anus
- Primary squamous cell carcinoma of perianal skin
- Primary squamous cell carcinoma of skin of anus
- Squamous cell carcinoma of anal margin
- Squamous cell carcinoma of anogenital area
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Squamous cell carcinoma of anal margin
- Squamous cell carcinoma 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.
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 › squamous cell carcinoma | C44.520 | – | – | – | – | – |
| skin NOS › anus › squamous cell carcinoma | C44.520 | – | – | – | – | – |
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 C44.520 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C44.520Overview
Is C44.520 (Squamous cell carcinoma of skin of trunk) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report squamous cell carcinoma of anal skin on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does C44.520 group to?
When squamous cell carcinoma 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 C44.520?
Under the General Equivalence Mappings, squamous cell carcinoma of anal skin converts to ICD-9-CM 173.52 (squam cell ca skin trunk). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
