2026 ICD-10-CM Diagnosis Code C44.90Unspecified malignant neoplasm of skin, unspecified
ICD-10-CM Codes›C00–D49›C43-C44›C44
- Billable — Valid for Submission
- Chronic Condition
C44.90 is a billable ICD-10-CM diagnosis code for unspecified malignant neoplasm of skin, unspecified. 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 - all other types.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Adverse effect from PUVA photochemotherapy
- Carcinoma of bone, connective tissue, skin and breast
- Disorder of skin due to radiotherapy
- Local recurrence of malignant neoplasm of skin
- Malignant epithelial neoplasm of skin
- Malignant neoplasm of adnexa of skin
- Malignant neoplasm of bone, connective tissue, skin and breast
- Malignant neoplasm of dermis
- Malignant neoplasm of nail apparatus
- Malignant neoplasm of skin
- Malignant neoplasm of skin caused by arsenic
- Malignant neoplasm of skin caused by radiation
- Malignant skin tumor with eccrine differentiation
- Malignant vascular tumor of skin
- Muir-Torré syndrome
- Occupational cancer of skin
- Pigmentation defects, palmoplantar keratoderma, skin carcinoma syndrome
- Primary malignant neoplasm of adnexa of skin
- Primary malignant neoplasm of sebaceous gland
- Primary malignant neoplasm of skin
- Primary malignant neoplasm of skin due to and following radiotherapy
- Primary malignant neoplasm of sweat gland
- PUVA therapy-associated skin malignancy
- Scarring alopecia of scalp due to malignant neoplasm of skin
- Skin disease caused by arsenic
- Toxicoderma
- Undifferentiated adnexal carcinoma of skin
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Malignant neoplasm of unspecified site of 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. |
|---|---|---|---|---|---|---|
| connective tissue NEC › skin (dermis) NEC [See Also: Neoplasm, skin, by site] | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
| nail [See Also: Neoplasm, skin, limb] | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
| scar NEC [See Also: Neoplasm, skin, by site] | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
| skin NOS | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
| skin NOS › limb NEC | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
| sudoriferous, sudoriparous gland, site unspecified | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
| sweat gland (apocrine) (eccrine), site unspecified | C44.90 | C79.2 | D04.9 | D23.9 | D48.5 | D49.2 |
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 C44.90 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C44.90Overview
Is C44.90 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified malignant neoplasm of skin, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does C44.90 group to?
When unspecified malignant neoplasm of skin, unspecified 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 C44.90?
Under the General Equivalence Mappings, unspecified malignant neoplasm of skin, unspecified converts to ICD-9-CM 173.90 (malig neo skin site NOS). 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.
